FSIS Cooking Guideline for Meat and Poultry Products (Revised Appendix A)

FSIS Cooking Guideline for

Meat and Poultry Products

(Revised Appendix A)

December, 2021

Document ID: FSIS-GD-2021-14

This guideline provides information on the

Agency regulatory requirements

associated with safe production of ready-

to-eat (RTE) products with respect to the

destruction of Salmonella and other

pathogens. It applies to small and very

small meat and poultry official

establishments although all meat and

poultry establishments may apply the

recommendations in this guideline. It

relates to 9 CFR 318.17(a)(1), 9 CFR

318.23, 381.150(a)(1), and 9 CFR 417.

Table of Contents

Preface ............................................................................................................................ 4

Purpose of this Guideline .......................................................................................... 4

History of this Guideline and Reason for Reissuance ............................................... 5

Changes from the Previous Versions ....................................................................... 6

How to Effectively Use this Guideline ....................................................................... 8

Questions Regarding Topics in this Guideline .......................................................... 9

Background ................................................................................................................... 10

What is Lethality? ................................................................................................... 10

Products and Processes Covered by this Guideline ............................................... 10

Products and Processes Not Covered by this Guideline ........................................ 11

Biological Hazards of Concern During Cooking ...................................................... 13

General Considerations for Designing HACCP Systems to Achieve Lethality by Cooking

. ..................................................................................................................................... 18

Addressing Lethality in the HACCP System ........................................................... 18

Alternative Lethality ................................................................................................ 20

Monitoring, Calibration, and Recordkeeping ........................................................... 20

Corrective Actions under HACCP Cooking Deviations ........................................... 22

FSIS Critical Operating Parameters for Cooking ........................................................... 23

Come-Up-Time (CUT) ............................................................................................ 23

Relative Humidity .................................................................................................... 25

Table 1. Critical Operating Parameters for FSIS Humidity Options........................ 26

Relative Humidity Resources .................................................................................. 28

Situations when Humidity is Not Needed ................................................................ 31

Endpoint Time-Temperature ................................................................................... 34

Table 2. Time-Temperature Combinations for Meat Products to Achieve Lethality

. .............................................................................................................................. 35

Additional Critical Operating Parameters for Poultry Products................................ 36

Table 3. Time-Temperature Combinations for Chicken Products to Achieve

Lethality .................................................................................................................. 37

Table 4. Time-Temperature Combinations for Turkey Products to Achieve Lethality

. .............................................................................................................................. 38

Resources for Customized and Alternative Support ...................................................... 40

Scientific Gaps Identified by FSIS .................................................................................. 41

Table 5. Scientific Gaps where Critical Operating Parameters From Older

Guidance May be Used .......................................................................................... 43

References .................................................................................................................... 49

Attachment A1. Customized Processes and Alternative Lethality Support ................... 55

Supporting an Alternative Lethality Target (e.g., 5-Log) .......................................... 57

Table 6. Time-Temperature Combinations for Meat Products to Achieve a 5-Log

Reduction ............................................................................................................... 59

Predictive Microbial Modeling to Support CUT ....................................................... 62

Designing Challenge Studies for Cooking .............................................................. 63

Attachment A2. Cooking Deviations .............................................................................. 66

Corrective Actions to Perform When a Cooking Deviation Occurs ......................... 66

Type 1. Missed Endpoint Time-Temperature ......................................................... 67

Type 2. Insufficient Humidity During Cooking ........................................................ 69

Type 3. Long Heating CUT .................................................................................... 70

Predictive Microbial Modeling ................................................................................. 72

Product Testing ...................................................................................................... 77

Table 7. FSIS Recommendations for Product Sampling and Testing After Each

Type of Cooking Deviation to Determine Product Disposition ................................. 77

Disposition after Testing Results ............................................................................ 79

Attachment A3. When can Products be Labeled as Pasteurized? ................................ 81

Attachment A4. Sources of Salmonella Contamination in RTE Products and Best

Practices to Address It ................................................................................................... 82

Under-Processing ................................................................................................... 82

Cross-Contamination .............................................................................................. 82

Ingredients Added After the Lethality Treatment ..................................................... 84

Food Handlers ........................................................................................................ 86

Animals .................................................................................................................. 86

Attachment A5. RTE Salmonella Self-Assessment Tool ............................................... 87

Attachment A6. Cooking Country-Cured Hams ............................................................ 90

Preface

This is a revised version of the FSIS Cooking Guideline for Meat and Poultry Products

(Revised Appendix A). It has been updated in response to comments received on the

previous version and renamed. In addition, the guideline has been revised to include

recommendations from previous versions and new updates based on up-to-date

science. The guideline also includes changes to improve its readability.

This guideline represents FSIS’s current thinking on these topics. Establishments that

utilized previous versions of Appendix A as support should either:

• Update to this 2021 FSIS Cooking Guideline (Revised Appendix A) or

• Identify alternative support by December 14, 2022.

The information in this guideline is provided to assist meat and poultry establishments in

meeting the regulatory requirements. The contents of this document do not have the

force and effect of law and are not meant to bind the public in any way. This document

is intended only to provide clarity to industry regarding existing requirements under the

regulations. Under the regulations, meat and poultry establishments may choose to

implement different procedures than those outlined in this guideline, but they would

need to validate and support how those procedures are effective.

This guideline is focused on small and very small plants in support of the Small

Business Administration’s initiative to provide small businesses with compliance

assistance under the Small Business Regulatory Enforcement Fairness Act (SBREFA).

However, all meat and poultry establishments may apply the recommendations in this

guideline. It is important that small and very small establishments have access to a full

range of scientific and technical support, and the assistance needed to establish safe

and effective Hazards Analysis and Critical Control Point (HACCP) systems. Although

large plants can benefit from the information, focusing the guideline on the needs of

small and very small establishments provides them with assistance that may be

otherwise unavailable to them.

Purpose of this Guideline

This guideline contains information to assist meat and poultry establishments producing

products that undergo cooking in complying with the HACCP regulatory requirements in

9 CFR 417. This guideline includes information on:

• Biological hazards during cooking.

• Regulatory requirements associated with the safe production of cooked ready-to-

eat (RTE) products.

• Options establishments can use to achieve lethality of Salmonella and other

pathogens.

• Processes that do not have validated research available (referred to as “scientific

gaps”) and options establishments can use until research is available.

• Resources for alternative support.

• Recommendations for evaluating cooking deviations.

Establishments can always seek guidance from State university extension service

specialists and HACCP Coordinators on developing programs and plans not provided in

this guideline to comply with HACCP regulatory requirements.

History of this Guideline and Reason for Reissuance

In the 1970s and 1980s, FSIS included prescriptive time, temperature, and humidity

operating parameters in the regulations for cooked beef, roast beef, and cooked corned

beef (42 FR 44217; 47 FR 31854; 48 FR 24314) in response to several outbreaks

associated with these products and research performed to determine how to prepare

them safely. When the Pathogen Reduction/Hazard Analysis and Critical Control Points

(PR/HACCP) final rule published in 1996, FSIS eliminated the prescriptive cooking

regulations and replaced them with performance standards requiring a 6.5-Log

reduction in Salmonella or alternative lethality for roast beef, cooked beef, and corned

beef, minimum internal temperature and holding times for fully cooked patties that

achieve a 5-Log reduction in Salmonella, and a 7-Log reduction in Salmonella or

alternative lethality for poultry products (9 CFR 318.17(a)(1), 9 CFR 318.23, 9 CFR

381.150(a)(1); see General Considerations for Designing HACCP Systems to Achieve

Lethality by Cooking, page 18. FSIS converted these former regulations to “Safe

Harbors” in an appendix to the final rule called Appendix A (64 FR 732).

Establishments have been using FSIS’s Appendix A, as published in 1999, as support

for cooking processes for many years. The original requirements and subsequent

guidance have been important to prevent human illness outbreaks and ensure the

production of safe food. See General Considerations for Designing HACCP Systems to

Achieve Lethality by Cooking, page 18 for more information on the current regulatory

requirements.

Over time, FSIS determined that some of its recommendations in the 1999 version of

Appendix A were vague, putting establishments at risk of producing unsafe products.

Additionally, some elements of the 1999 version of Appendix A were misunderstood or

overlooked, resulting in FSIS guidance being applied in ways that increased food safety

risks to consumers and potential risks to industry, including the risk of foodborne illness

outbreaks. FSIS also determined establishments were broadly applying the

recommendations for operating parameters in Appendix A beyond those meat and

poultry products it was originally designed to support.

To provide the needed updates and clarifications, FSIS issued revisions of both its

Cooking (Appendix A) and Stabilization (Appendix B) guidelines in 2017. The 2017

version of the guidelines took into account new and emerging technologies, processes,

and science. FSIS has updated this guideline in response to comments received on the

2017 version and has included additional options for cooking support based on updated

science and technology. The Agency is releasing this current 2021 version of the

FSIS Cooking Guideline for Meat and Poultry Products (Revised Appendix A) to

replace all previous versions.

Changes from the Previous Versions

This guideline dated December 14, 2021 is final. FSIS will update this guideline, as

necessary, should new information become available.

FSIS made the following changes to this guideline to reflect the comments received on

the previous version during the comment period and to include additional scientific

information.

For Appendix A, FSIS made changes to specify:

• The following products are not covered by the guideline (page 11): Fish of the

Order Siluriformes, pork rind pellets, rendered lard and tallow, dried products

processed under dry conditions, partially heat-treated NRTE products, and RTE

multi-hurdle products.

• The food safety significance of FSIS’s recommendations for relative humidity

(page 17).

• That relative humidity should be addressed for all cooked products (including

poultry) unless the establishment can support that humidity does not need to be

addressed. FSIS has not changed the relative humidity options (page 26) other

than re-emphasizing that they apply to all products.

• Additional resources for selecting a relative humidity option when following

FSIS’s cooking guidance (page 28).

• The situations when relative humidity does not need to be addressed including

by providing more information about situations considered to be direct heating

(page 31) (e.g., by clarifying that relative humidity does not need to be addressed

for meat patties cooked using FSIS’s time-temperature table for meat, if the

patties are cooked using direct heat (on page 31)). Previous guidance indicated

it did not need to be addressed for meat patties with the assumption all meat

patties are cooked using direct heat which is no longer the case.

• That natural casings become semipermeable during cooking, maintaining

moisture in the product, so that additional documentation to address relative

humidity is not needed (page 33).

• More detailed information for evaluating product safety following a heating

deviation (page 66). The revision also removes the recommendation for using

the ComBase model for Staphylococcus aureus growth (which was not validated)

because of the development and validation of the Danish Meat Research

Institute (DMRI) Staphtox model in 2018.

• Where gaps exist, recommendations from its older cooking guidance can be

used until research is completed (see, Table 5. Scientific Gaps where Critical

Operating Parameters From Older Guidance May be Used, page 43) for:

1. Products cooked for short times at high temperatures.

2. Products cooked using microwave cooking methods that are not

designed to control relative humidity.

3. Products cooked using cooking methods that are not designed to

control relative humidity.

4. Other processes that may inherently maintain relative humidity

around the meat and poultry filling but cannot follow one of the relative

humidity options.

5. Processes where the drying step comes before cooking under moist

conditions.

6. Products with long heating come-up-times (CUTs).

• That information is included about a listeriosis outbreak associated with a cooked

country-cured ham product and recommendations for establishments that cook a

similar product once (page 90).

For Appendix A, FSIS removed:

• Information about how establishments could remove poultry rolls from the

cooking medium before product has achieved the target endpoint temperature

and immediately apply another heating or processing method (64 FR 732).

Since FSIS has clarified that limiting heating CUT is a critical operating

parameter for applying any of FSIS cooking guidance (including these older

options), the parameter to “immediately fully cook” poultry rolls subject to multiple

heating mediums and processes has been removed.

• Specific recommendations for conducting a Salmonella baseline study on raw

source materials as support for using cooking critical operating parameters that

achieve a 5-Log reduction in Salmonella for meat products instead of a 6.5 or 7-

Log reduction. This information was removed since it was interpreted to apply to

all establishments when it was only intended for establishments that wanted to

support a lower level of pathogen reduction from cooking. In addition, FSIS is

not aware of any establishments that have pursued such baseline sampling.

In addition to these changes, the guidelines format was restructured to make it easier to

use as described in the next section. This list of changes is not comprehensive, so

establishments should read the section titled FSIS Critical Operating Parameters for

Cooking and other relevant sections as needed.

How to Effectively Use this Guideline

As explained above in the Changes from the Previous Versions, the guidelines format

was restructured to make it easier to use. Specifically, the guideline is organized to

include the following topics in the body of the guideline:

• Biological hazards during cooking.

• Regulatory requirements associated with the safe production of cooked ready-to-

eat (RTE) products.

• Options establishments can use to achieve lethality of Salmonella and other

pathogens.

• Processes that do not have validated research available (referred to as “scientific

gaps”) and options establishments can use until research is available.

Information included in the body of the guideline is intended as scientific support that

can be used alone by establishments to meet Element 1 of validation (9 CFR

417.4(a)(1)) and to support decisions in the hazard analysis (9 CFR 417.5(a)(1)).

The following topics are included in attachments to the guideline:

• Resources for alternative support and

• Recommendations for evaluating cooking deviations.

Information provided in the attachments is not sufficient to use as sole support and

additional documentation is needed. For example, Attachment A1. Customized

Processes and Alternative Lethality Support (page 55), contains descriptions or brief

summaries of available scientific articles. However, the summaries are not considered

adequate support on their own because they do not contain the details of each study.

For this reason, establishments must have the full copy of the article on-file as scientific

support for their HACCP System. The summaries are provided to help establishments

identify journal articles related to their process. Each establishment needs to determine

if the operating parameters of a particular study match the establishment’s process.

Establishments are not limited to using the scientific articles listed and summarized as

support. In addition, Attachment A2. Cooking Deviations (page 66), contains

recommendations for evaluating product safety in the event of a deviation but this

information is not considered adequate support on its own because establishments

should perform predictive microbial modeling and may conduct sampling and testing in

order to support product disposition. Other information included in attachments is

intended to be supplementary.

Questions Regarding Topics in this Guideline

If after reading this guideline you still have questions, FSIS recommends searching the

publicly posted Knowledge Articles (“Public Q&As”) in the askFSIS database. If after

searching the database, you still have questions, refer them to the Office of Policy and

Program Development through askFSIS and select HACCP Deviation & HACCP

Validation as the Inquiry Type or by telephone at 1-800-233-3935.

Documenting these questions helps FSIS improve and refine present and future

versions of the guideline and associated issuances.

FSIS Cooking Guideline for Meat and Poultry Products

(Revised Appendix A)

Background

What is Lethality?

Lethality treatments are processes used by

establishments to eliminate Salmonella and other

pathogens in RTE products. Lethality treatments achieve

a specific reduction in the number of Salmonella and other

pathogens in the product (i.e., an “X-Log10 colony forming

units per gram

(CFU/g)” reduction). The combination of

one or more lethality treatments must be sufficient to

eliminate or adequately reduce Salmonella and other

pathogens to undetectable levels and prevent the

production of toxins or toxic metabolites in the RTE

product (e.g., from Staphylococcus aureus).

Establishments may use a variety of different lethality

processes, such as:

• Cooking the product (covered in this guideline).

• Fermentation.

• Drying.

• Salt-curing.

• Other processes that make the product safe for

consumption.

Products and Processes Covered by this

Guideline

This guideline addresses lethality of pathogens (e.g.,

Salmonella) in meat and poultry products

by heat

treatment (cooking) including for products that are cooked

to lethality but classified under a not-ready-to-eat HACCP

plan.

NOTE: FSIS has provided additional information about

the safe production of meat and poultry jerky products in

In the rest of this document, Log

colony forming units per gram (Log

CFU/g) will be annotated simply

as “Log.” All notations of “Log” should be read as in the unit Log

CFU/g unless other information is

provided.

Throughout this document references to “meat and poultry products” may be considered inclusive of

meat by-products, meat food products, and poultry food products as defined in 9 CFR 301.2 and 9 CFR

381.1, unless otherwise stated (e.g., Products and Processes Not Covered by This Guidance).

KEY DEFINITIONS

A ready-to-eat (RTE)

product is defined as a

meat or poultry product

that is in a form that is

edible by the end

consumer without

additional preparation to

achieve food safety and

that may receive

additional preparation for

palatability, aesthetic, or

culinary purposes (9

CFR 430.1).

Lethality is the process

(or combination of

processes) that ensure a

specific, reduction in the

number of Salmonella and

other pathogens in the

product (i.e., an “x-Log”

reduction). Lethality

processes eliminate or

adequately reduce

Salmonella and other

pathogens and prevent the

formation of their toxins or

toxic metabolites,

facilitating the production

of a safe RTE food

product.

the FSIS Compliance Guideline for Meat and Poultry Jerky Produced by Small and Very

Small Establishments. The information for jerky production remains in a separate

guideline because of the complexities of the process, including drying procedures, and

to help address questions from small and very small processing establishments.

Products and Processes Not Covered by this Guideline

The recommendations in this guideline do not apply to the following specific products:

Fish of the Order Siluriformes (e.g., catfish)

FSIS cooking guidance was not validated for fish of the order Siluriformes. Therefore,

this guidance should not be used for fish.

Fish establishments may use the cooking guidance in Table A-3 of The Food and Drug

Administration’s (FDA’s) Fish and Fishery Products Hazards and Control Guidance as

support for the cooking step of fish products. The time-temperature recommendations

are designed to achieve a 6-Log reduction in Listeria monocytogenes (Lm).

Pork Rind Pellets

Establishments may cook pork skins in pork fat or oil for several hours rendering the fat

and reducing the skin into pellets. This intermediate product is then further processed

by frying to produce a finished product such as pork rinds, cracklins (cracklings), or

chicharrones. FSIS cooking guidance does not apply to the cooking or rendering of

pork skins into a pellet. Establishments may use the cooking requirements in 9 CFR

94.8(b)(4) as support for cooking pork skins into a pellet. Although these are Animal

Plant and Health Inspection Service (APHIS) requirements for imported pork skins from

countries where foot-and-mouth disease, African swine fever, classical swine fever, or

swine vesicular disease exist, these cooking requirements ensure at least a 6.5-Log

reduction of Salmonella (Juneja, et al., 2001a; Murphy et al., 2003; Murphy et al., 2004).

NOTE: FSIS cooking guidance may be used for cooking of pork skins for products other

than pork rind pellets (e.g., for use in pickled products) and for frying of pork rind pellets

into popped pork skins. Guidance for monitoring the cooking critical limit for these

products can be found in the Key Question on page 21.

Rendered Lard and Tallow

FSIS cooking guidance does not apply to the rendering of animal fats, such as lard and

tallow, which, due to the high fat content, generally need to reach higher temperatures

and longer dwell

times to achieve the same reductions in Salmonella (Ramirez-

Hernandez et al., 2018). However, based on the D values (time at a constant

temperature necessary to destroy 90% or 1-Log of the target organism) reported by

Ramirez-Hernandez et al. (2018), the cooking requirements for rendering in 9 CFR

315.1(a) are adequate to ensure an animal fat rendering process achieves at least 6.5-

“Dwell time” ref ers to the time a product is held at a specific temperature. Other commonly used terms

such as “hold time” or “rest time” may be considered synonymous for the purpose of this guideline.

Log reductions of Salmonella. Therefore establishments may

use 9 CFR 315.1 as support for a lard or rendering process,

provided the critical operational parameters (≥ 170°F for ≥ 30

minutes) are met throughout the product.

Dried Products Processed Under Dry Conditions

FSIS cooking guidance does not support lethality for a

process that relies on drying alone (e.g., biltong), nor does

this guidance support a process where the drying step comes

before a cooking step that does not apply humidity or does

not apply humidity during cooking at sufficient levels to

rehydrate the product surface (e.g., biltong or country-cured

ham that is cooked in an unsealed oven after drying). This

guidance also does not support lethality for a dried product

cooked under moist conditions several times after drying

(e.g., country-cured ham that is cooked in a sealed oven

several times after the hams have been salt-cured and dried).

Such dried products are typically considered intermediate

moisture foods (i.e., those foods that do not require

refrigeration to control pathogens). The water activity range

of foods considered intermediate moisture varies in the

literature. For example, FDA classifies intermediate moisture

foods as those with a water activity between 0.60 and 0.85

(FDA, 2018). However, some meat and poultry products may

have a water activity > 0.85 and still be considered

KEY DEFINITIONS

Stabilization is the

process of preventing or

limiting the growth of

spore-forming bacteria

capable of producing

toxins either in the

product or in the human

intestine after

consumption.

Stabilization processes

may include cooling, hot-

holding, or meeting and

maintaining a certain pH

or water activity level and

other processes, such as

drying and fermentation/

acidification that render

the product shelf-stable or

safe at room

temperatures.

“intermediate moisture” because of other factors such as pH and salt concentration

(Leistner, 1987). For example, country-cured ham has an average water activity of 0.88

but is considered shelf-stable due to the combination of water activity, high salt, and

nitrite (Mikel and Newman, 2003; Reynolds et al., 2001).

Establishments that apply these types of processes must identify other support for their

HACCP System (9 CFR 417.5(a)(1) and 9 CFR 417.4(a)(1)).

NOTE: This guidance includes critical operating parameters for cooking products which

are dried, then cooked under moist conditions. Scientific Gaps Identified by FSIS

describes critical operating parameters (page 47) and Attachment A6. Cooking

Country-Cured Hams includes additional tips, specific to country-cured hams (page

90).

Partially Heat-Treated NRTE Products

This guideline does not cover partially heat-treated products that are not ready-to-eat

(NRTE) and did not reach a validated lethality time-temperature combination (for

example: partially heat-treated bacon and hams). These products are addressed in the

FSIS Stabilization Guideline for Meat and Poultry Products because cumulative growth

of Clostridium perfringens and Clostridium botulinum are hazards of concern over the

course of partial cooking and cooling processes.

NOTE: As noted under the Products and Processes Covered by this Guideline, this

guideline may be used for products that are cooked to lethality but classified under a

Not RTE (NRTE) HACCP plan. For such products, please refer to the product

reclassification guidance in the Listeria Guideline, Attachment 1.2 on pages 22-23 and

Appendix 1.2 on pages 28-29 for guidance related to labeling, HACCP categorization,

and intended use.

RTE Multi-hurdle Products

This guidance does not address the safe production of products that rely on multiple

hurdles to achieve lethality and shelf-stability (e.g., fermented and dried sausage).

However, some regulatory information associated with such products is included in

General Considerations for Designing HACCP Systems to Achieve Lethality by

Cooking, page 18.

NOTE: Stabilization requirements and recommendations for cooling meat and poultry

products after heat treatment are described in the FSIS Stabilization Guideline for Meat

and Poultry Products.

Biological Hazards of Concern During Cooking

The following section is designed to complement FSIS’s Meat and Poultry Hazards and

Control Guide and to further assist establishments in conducting a hazard analysis for

cooked meat and poultry products as required by 9 CFR 417.2(a)(1) and for supporting

decisions in their hazard analysis as required by 9 CFR 417.5(a)(1).

The following hazard is present in raw products whose outgrowth during the

heating come-up time should be controlled:

• Staphylococcus aureus (S. aureus)

The following are hazards present in raw products that the lethality treatment

should be designed to destroy:

• Salmonella

• Shiga toxin-producing Escherichia E. coli (STEC) (in beef)

• Campylobacter (in poultry)

• Lm

• Trichinae spiralis and Toxoplasma gondii (in pork, especially feral or non-

confinement raised swine)

NOTE: Although all of these hazards are a concern, Salmonella is considered an

indicator of lethality because the thermal destruction of Salmonella in cooked products

would indicate the destruction of most other pathogens (64 FR 732).

More details about S. aureus and Salmonella (an indicator of lethality) can be found on

the following page.

S. aureus

S. aureus is a bacterial pathogen that causes nausea, vomiting, and abdominal

cramping with or without diarrhea. The Centers for Disease Control and Prevention

(CDC) estimates over 240,000 illnesses annually in the U.S. are attributed to S. aureus

(Scallan et al., 2011). S. aureus causes illness when the bacteria grows to high levels

in food and one or more heat-stable enterotoxins are produced (Kadariya et al., 2014).

Various types of foods serve as the optimum vehicle for S. aureus. The pathogen has

been identified in meat products, such as fermented salami and brine-injected hams. In

the 1980s, S. aureus enterotoxin outbreaks were frequently attributed to hams.

Continued outbreaks at hotels, restaurants and institutions as documented in the

National Outbreak Reporting System (NORS)

highlight that S. aureus is still a concern

in hams particularly when prepared in these settings. For example, between 2013 to

2018, at least six S. aureus enterotoxin outbreaks at hotels, restaurants and institutions

were reported in NORS in which ham was the suspected food vehicle. S. aureus can

contaminate raw meat and poultry from the animal hide, skin, or tissue during slaughter.

After slaughter and cooking, RTE meat or poultry products can be contaminated with S.

aureus from handling by individuals carrying the organism. This pathogen is the main

food safety concern during long heating come-up-times (CUT) (that is the amount of

time product temperature is between 50 to 130°F while heating). S. aureus can be

present on the raw meat or poultry and grow to high enough levels to produce a toxin in

the food. Growth occurs from 45 to 118°F, but effectively begins at 60˚F, especially in

raw meats where the growth of other bacteria is inhibited by nitrite or salt. The critical

level for human illness is 5-Log or higher which allows enterotoxin production (Kadariya

et al., 2014). The toxin is not destroyed by the critical operating parameters described

in this cooking guideline.

FSIS recommends limiting the growth of S. aureus during processing to 2-Log or less.

Normal levels of S. aureus in raw meat are usually 2-Log (Doyle and Buchanan, 2013;

IFT, 2003; Waldroup, 1996). Limiting growth to 2-Log or less allows for a margin of

safety before S. aureus would produce toxins. Conditions that allow 3-Log growth are

considered a public health concern because they would result in a total of 5-Log S.

aureus in the product which is considered the minimum critical level for human illness

(Kadariya et al., 2014).

To limit S. aureus growth, some establishments formulate products with antimicrobials

such as phosphate or lactate. But the most common practice is to limit the amount of

time products spend in the temperature range where S. aureus grows the fastest (i.e.,

50 to 130°F). This guideline identifies CUT as a critical operating parameter to ensure

lethality by cooking when applying the time-temperature tables (see FSIS Critical

Operating Parameters for Cooking on page 23). FSIS is aware that establishments

preparing some products (e.g., ham or beef brisket) may not be able to follow FSIS’s

Come-Up-Time Option because of the thermodynamics of the heating process.

Therefore, FSIS identified long CUT as a Scientific Gap since support does not exist for

many common processes (page 48). This gap supports the use of any of FSIS’s

applicable time-temperature combinations (pages 35, 37, 38) and relative humidity,

https://www.cdc.gov/nors/index.html

KEY DEFINITIONS

Critical operating

parameters are those

parameters of an

intervention that must be

met for the intervention to

operate effectively and as

intended. Such

parameters include but

are not limited to time,

temperature, water

activity, concentration,

relative humidity, and type

of equipment (to the

extent that the use of

different equipment would

result in an inability to

achieve the critical

parameters of the study).

without considering CUT as a critical operating parameter until research can be

complete.

Salmonella

Salmonella is a bacterial pathogen that causes diarrhea and fever. Infection with

Salmonella may result in arthritis (Ajene et al., 2013). The CDC reports that

nontyphoidal Salmonella species (spp.) is one of the leading causes of foodborne

illness, with an estimated 1 million cases of foodborne Salmonella infection annually in

the U.S (Scallan et al., 2011). Salmonella spp. infections are the second leading cause

of foodborne illness in the United States. Meat and poultry outbreaks are frequently

associated with Salmonella spp.

Salmonella occurs naturally in raw animal products; however, Salmonella should not be

found in RTE meat and poultry products because these products have undergone a

lethality treatment. Also, RTE products are intended to be consumed without further

preparation for safety (i.e., cooking), and if pathogens are present, their consumption

may cause illness. FSIS considers all RTE meat and poultry products that are

contaminated with Salmonella, as well as Listeria

monocytogenes and STEC, to be adulterated under the Federal

Meat Inspection Act and Poultry Products Inspection Act (21

U.S.C. 601(m)(1)) and 453(g)(1)). Any detectable Salmonella or

other pathogens of concern adulterates RTE products (64 FR

732).

Salmonella as an Indicator of Lethality

Meat and poultry products may be contaminated with Salmonella

during the slaughter and dressing process and by cross-

contamination in the processing environment when insanitary

conditions are present. For cooked products, FSIS recommends

that establishments use Salmonella as an indicator of lethality

because the thermal destruction of Salmonella in cooked

products would indicate the destruction of most other pathogens

(64 FR 732). If the establishment’s scientific support

demonstrates that the lethality treatment achieves sufficient

reduction in Salmonella, it does not need to provide additional

support that adequate reduction of other pathogens such as

STEC, Campylobacter, Lm, Trichinae spiralis or Toxoplasma

gondii is achieved. As stated in the FSIS Compliance Guideline

HACCP Systems Validation, establishments should not use

pathogens other than Salmonella as indicators of lethality for

cooked products unless the alternate pathogen displays similar

or higher resistance to the lethality processes.

NOTE: While Salmonella is considered an indicator of lethality

for validation purposes, in the event of a deviation where the

establishment missed its time-temperature parameters or

applied insufficient relative humidity, FSIS recommends testing for other pathogens of

concern (e.g., E. coli O157:H7 and Lm) because the absence of Salmonella does not

assure the absence of other pathogens since the establishment was unable to follow

the critical operational parameters in its scientific support. In addition, depending on the

type of deviation, other pathogens may also be of concern (e.g., C. perfringens and C.

botulinum). For more information see Attachment A2. Cooking Deviations, page 66.

How to Control Salmonella

Establishments must ensure the target Log reduction of Salmonella and other

vegetative pathogens is achieved throughout the product. To ensure vegetative

pathogens, including Salmonella, are killed on the interior of the product, the endpoint

time-temperature combination the product achieves is a critical operating parameter.

Most often, the target temperatures used during cooking reported in scientific support

documents and this guideline are the internal temperatures that the product should

reach. FSIS has found that some establishments use the recommendations established

for internal product temperature to set critical limits for the oven temperature. However,

setting the oven temperature to the temperature identified in the FSIS time-temperature

tables is not appropriate because doing so does not ensure that the product will reach

the same target internal temperature.

In addition to the product temperature, the amount of time the product is held at this

temperature (also known as the dwell time) is also critical to ensuring that adequate

lethality is achieved. If the product is held at the target temperature for less time than

specified in the time-temperature tables in this guideline, then adequate lethality may

not be achieved.

To ensure a process achieves the target Log reductions of Salmonella on the surface of

the product, moisture during cooking is a critical factor. Moisture (e.g., relative humidity)

around a product during cooking promotes lethality on the product surface in two ways:

• Moist cooking reduces surface evaporation from the product during heating

(evaporative cooling). Producing products under conditions of high moisture

early in the cooking process reduces evaporative cooling allowing product

surfaces to reach higher temperatures resulting in a greater reduction in

microorganisms; and

• Moist cooking keeps the product surface (and any pathogens) wet which

prevents product drying. Product drying reduces the water activity and

concentrates solutes (e.g., sugar and salt). Research has demonstrated that

bacteria can become more heat tolerant as their moisture levels decrease, and

increased concentrations of solutes, especially salt, increase the heat resistance

of bacteria (Buege et al., (2006), Boles et al., (2004), and Sindelar et al., (2016)).

Therefore, drying of the product surface before pathogens are destroyed will

increase pathogen heat resistance and allow the pathogens to survive the

heating process.

By incorporating moisture (e.g., relative humidity) to minimize evaporation and the loss

of surface moisture from the product, the D values (time at a constant temperature

necessary to destroy 90% or 1-Log of the target organism) that are the basis for the

time-temperature combinations, will remain valid (Goepfert, 1970; Goodfellow and

Brown, 1978). If evaporation, drying, or an increase in solute concentration is likely to

occur, the times and temperatures in scientific studies and supporting documentation

are not likely to be sufficient to provide the required lethality.

How does Moisture Ensure Bacteria on the Surface are Killed During Cooking?

During cooking, achieving a high oven temperature and internal product temperature

alone are not enough to ensure the final product is free of harmful bacteria.

Establishments need to make sure that cooking is done in a moist environment to

ensure lethality. When relative humidity is low, oven air is dry, and a process called

evaporative cooling increases, which is something we do not want. Evaporative

cooling is the same thing that allows humans to keep cool by sweating. When you get

too hot, you produce sweat, and when that sweat evaporates, it cools you down.

Evaporation equals cooling.

When you get too

hot…

…you produce

sweat.

When that sweat

evaporates…

…it cools you down.

Just like on a person’s skin, evaporative cooling cools down the surface of meat and

poultry during cooking. Although the oven is hot, because the surface of the product is

cooling down, that moisture evaporation can actually prevent the surface of the product

from becoming hot enough to kill off harmful bacteria. We can reduce evaporative

cooling by keeping the humidity in the oven high. That way the moisture in the product

does not evaporate as quickly, keeping the meat’s surface moist and hot and resulting

in an adequate bacterial kill. Why

does this work?

Imagine that you are in New

Mexico or Nevada where it is really

hot, but dry. If you’re outside,

you’re more likely to sweat and

that sweat will cool you down, so

you don’t feel as hot. Now imagine

you’re in Florida where it is not

only really hot, but also humid. If

you’re outside where it is humid,

your skin’s surface will stay sweaty

and hot, your sweat will not

Desert

Dry Heat

= Cooling Down

VS.

Tropical

More Humidity

= Less Cooling

evaporate, and you will not cool down. Since the air is already saturated, or full of

moisture (humid), there is less evaporation from your body and, therefore, less cooling.

The way humidity keeps you hot in Florida is the same way moisture keeps meat and

Evaporation

Cooling

poultry products hot, too.

General Considerations for Designing

HACCP Systems to Achieve Lethality

by Cooking

Addressing Lethality in the HACCP System

FSIS has established performance standards in the

regulations for specific ready-to-eat (RTE) products. The

performance standards for specific products set required

levels of Salmonella lethality during cooking as follows:

• Cooked poultry products must be processed to

achieve at least a 7-Log reduction of Salmonella or an

alternative lethality per 381.150(a)(1).

• Roast, cooked, and corned beef must be processed

to achieve at least a 6.5-Log reduction of Salmonella

or an alternative lethality (e.g., at least a 5-Log

reduction)) per 9 CFR 318.17.

• Cooked uncured meat patties must be processed to

meet or exceed the time-temperature combinations

listed in 9 CFR 318.23, which will achieve a 5-Log

reduction of Salmonella (and other pathogens

including STEC).

For products that are not subject to a performance standard,

FSIS recommends the following pathogen Log reductions

(i.e., targets) be achieved in order to support decisions in the

hazard analysis (9 CFR 417.5(a)(1)):

• For cooked meat products, FSIS recommends that

establishments achieve a target 6.5-Log or 5-Log

reduction of Salmonella in their process. To use a

target 5-Log reduction, establishments should provide

additional support for the safety of their process (see

Supporting an Alternative Lethality Target (e.g., 5-Log)

page 57).

• For shelf-stable meat products, FSIS recommends

that establishments achieve a target 5-Log reduction

of Salmonella (see How is Alternative 5-Log Lethality

Related to Risk of Foodborne Illness? page 57).

KEY DEFINITIONS

Performance standards

described in this guideline

are quantifiable pathogen

reduction levels or growth

limit requirements set by

FSIS for lethality and

stabilization of certain meat

and poultry products.

A Log reduction is a 90%

reduction of a pathogen.

For example, a 2-log

reduction is a 99%

reduction of a pathogen and

a 3-log reduction is a 99.9%

reduction of a pathogen in a

product.

Targets are quantifiable

pathogen reduction levels

or growth limits set by the

establishment to produce

safe products in the

absence of regulatory

performance standards.

An alternative lethality is a

treatment that achieves a

different (often lower) Log

reduction than what is

prescribed in the

regulations for certain

products, but still achieves

an equivalent probability

that no viable Salmonella

cells remain in the finished

product, nor other

pathogens and their toxins

or toxic metabolites. An

alternative lethality prevents

adulteration and must be

demonstrated to be

achieved throughout the

product (9 CFR

318.17(a)(1)).

An establishment should identify the performance standard or specific Log reduction

target its process is designed to achieve in its HACCP plan or supporting

documentation. If it does not, and FSIS cannot determine the pathogen reduction level

the process achieves, FSIS may determine the establishment lacks support for its

decisions related to Salmonella control (9 CFR 417.5(a)(1)). In addition, according to 9

CFR 417.2(c)(3), establishments must design their critical limits for Critical Control

Points (CCPs) to meet all applicable performance standards and targets.

NOTE: If an establishment uses the time-temperature tables provided in this guideline

or cooks beef patties according to 9 CFR 318.23, it does not need to indicate the

specific Log reduction that its process achieves. It would be sufficient for the

establishment to indicate that it uses time-temperature combinations from one of these

documents as these regulations were designed to achieve a 5-log reduction in

Salmonella and other pathogens including STEC.

Establishments are also required to validate that their HACCP system works as

intended to address these hazards (9 CFR 417.4(a)). For more information on

validation see the HACCP Systems Validation Guideline.

Key Question

Question: When a RTE meat food product is a mixture of meat and poultry such that the

product has a meat legend, and the establishment is following this cooking guideline, does the

RTE meat food product need to comply with the regulatory requirement found in 9 CFR

381.150(a)(1)?

Question: If a RTE meat food product has any amount of poultry in it, does it automatically

have to meet the poultry Log reduction in the FSIS Time-Temperature Tables?

Answer: Yes to both questions.

RTE meat or poultry food products consisting of any combination of meat and poultry must meet

the poultry lethality performance standard in 9 CFR 381.150(a)(1). Under the published final

rule "Performance Standards for the Production of Certain Meat and Poultry Products," cooked

product with any amount of poultry needs to meet the lethality requirements for the production of

fully cooked poultry products (9 CFR 381.150(a)(1)) which stipulate a 7-Log Salmonella

reduction or an alternative lethality that achieves an equivalent probability that no viable

Salmonella organisms remain in the finished product. This provision is based on the FSIS

national microbiological "baseline" survey of raw whole and ground meat and poultry products,

which found higher levels of Salmonella in poultry than in meat (USDA 1994, 1996a-f).

Consequently, FSIS established a higher lethality performance standard for RTE poultry

products than for meat (based on highest "worst case" levels).

Alternative Lethality

An alternative lethality is a treatment that achieves a different (often lower) Log

reduction than what is prescribed in the regulations but still achieves an equivalent

probability that no viable Salmonella cells remain in the finished product, as well as

ensures the reduction of other pathogens and their toxins or toxic metabolites (e.g.,

from S. aureus) necessary to prevent adulteration. Establishments may use alternative

lethality treatments to meet the performance standards (9 CFR 318.17(a)(1) and 9 CFR

381.150(a)(1)). When using an alternative lethality treatment (e.g., at least a 5-Log

reduction of Salmonella), the establishment must validate its HACCP system to ensure

that no viable Salmonella organisms (that is no organisms capable of causing human

illness) remain in the finished product. Risk assessments have demonstrated that

achieving a 5-Log reduction of Salmonella (instead of a 6.5-Log reduction) in cooked

meat and poultry products that are not shelf stable is less protective of public health

(Refer to text box: How is Alternative 5-Log Lethality Related to Risk of Foodborne

Illness? page 57). Therefore, to use these lower targets, the establishment must

provide additional support for its process as described in Attachment A1. Customized

Processes and Alternative Lethality Support: Supporting an Alternative Lethality Target

(e.g., 5-Log) on page 55. In contrast, risk assessments have shown that for shelf-stable

meat and poultry products, a 5-Log reduction of Salmonella (instead of a 6.5-Log or 7-

Log reduction) is sufficient. Therefore, no additional support is needed to use a 5-Log

reduction process in these shelf-stable products (9 CFR 417.5(a)(1) and 9 CFR

417.4(a)(1)).

Monitoring, Calibration, and Recordkeeping

The establishment’s cooking procedures should be designed to ensure all products in a

batch or lot achieve lethality, and the monitoring procedures should be designed to

detect a deviation when it occurs. To achieve these goals, establishments should

carefully consider the selection of the critical limit, as well as the design of their

monitoring procedures. Lessons learned from several recalls attributed, in part, to

insufficient monitoring procedures are shared on page 22.

Selection of the critical limit

Establishments producing cooked meat and poultry products should have sufficient

monitoring equipment, including recording devices, to assure that the time, temperature,

and relative humidity operating parameters of their processes are being met. With any

monitoring equipment, the establishment should take the normal variation of the

monitoring equipment into account when designing the critical limits. For example, if a

minimum internal temperature of 165°F is necessary to destroy pathogens in a product

and the thermometer has an accuracy of ± 1°F (plus or minus one degree), then the

critical limit should be set no lower than 166°F. The written reasoning and equipment

specification materials should be kept as part of the establishment’s supporting

documentation for its HACCP plan and the selection of its critical limit (9 CFR

417.5(a)(2)). All supporting documents and data from the recording devices must be

made available to FSIS employees upon request (9 CFR 417.5).

Selection of the monitoring procedures

Establishments are required to maintain documents supporting the selection of

monitoring procedures and associated monitoring frequencies (9 CFR 417.5(a)(2)). It is

important that establishments take into account variation within the cooking process

when developing monitoring procedures to ensure the procedures they develop can

identify any deviations.

In addition, to accurately measure the internal temperature of the meat or poultry

product, an establishment should understand the factors that can affect this

temperature. These factors include cold spots in the oven, as well as variations in oven

temperature during different seasons. Establishments should be aware that updated

smokehouses that contain alternating or rotating dampers that result in varying

breakpoints throughout the oven do reduce the temperature difference throughout the

oven, but they do not eliminate it. Although monitoring the internal product temperature

is strongly encouraged, an establishment can use the oven or smokehouse temperature

in place of the product temperature, provided that the establishment has a consistent

product and process and has sufficient data on file correlating the oven temperature

selected with the internal product temperature in the scientific support.

A disadvantage with monitoring oven temperature alone is that it may make supporting

product disposition after a cooking deviation more difficult. In many cases, FSIS

recommends using predictive microbial modeling programs to evaluate potential

hazards (see Attachment A2. Cooking Deviations on page 66). Microbial modeling

programs use product temperature to predict pathogen growth and potential Log

outgrowth or reductions achieved. Without product temperature records, the

establishment would need other support (e.g., product testing) to determine product

disposition.

Key Question:

Question: How does an establishment develop a monitoring procedure for measuring endpoint

temperature in meat or poultry products that are fried crispy such that a probe cannot be

inserted into the product to measure internal temperature (e.g., popped pork skins, and bacon

slices, pieces, or bits) because the product is too thin or hard or because the thin product cools

as soon as the product exits the cooking medium?

Answer: Depending on the product type, there are different recommendations. For example,

for a product such as bacon slices, it may be possible to cut a slice twice as thick as normal so

that the probe can be inserted. If this thicker piece reaches the lethality temperature, the thinner

pieces should as well. This procedure is also recommended for jerky. It is not recommended to

fold a piece of product over the thermometer, as this has been found to result in inaccurate

temperatures (Buege et al., 2006). For small products, such as bacon pieces or bits, it may be

possible to pile the pieces or bits around the thermometer for measurement. If none of these

procedures can be used, establishments may use other quantifiable measures such as a color

scale value that is correlated to crispiness or the number of pieces that pass as "fried until

crispy in all parts" based on a visual assessment as the critical limit for lethality for these

products due to the physical challenges in monitoring the internal temperature, and the lack of

outbreaks associated with them.

Lessons Learned from Undercooked Product Recalls

In 2016 and 2017, there were five recalls associated with under-cooked RTE poultry

products (RC-106-2016, RC-110-2016, RC-115-2016, RC-017-2017, and RC-037-

2017). For each of these recalls, FSIS determined that even though the establishments

had documentation showing the critical limit (either 160°F or 165°F) was met, there

were still pieces that may have entered commerce undercooked, indicating a loss of

process control and insufficient monitoring procedures to identify a process deviation.

Investigations revealed a variety of concerns related to monitoring procedures, including

taking temperatures from products not in the coldest spot, taking multiple product

temperatures, and averaging the results of multiple temperature measurements as

opposed to recording the lowest temperature.

Investigations also revealed a variety of contributing factors for inadequate cooking

including:

• Raw product was partially frozen.

• Belt speed was increased.

• Shorter dwell time and lower oven temperature than normal were used.

• Product was stacked during sous vide cooking, preventing full immersion of the

bags into the liquid cooking medium.

• Higher than normal product load overwhelmed the oven.

Each of these practices may have led to uneven or inadequate cooking. These findings

also highlight the importance of maintaining process control of critical operating factors,

such as oven temperature, product load, and belt-speed that affect the final product

temperature, dwell time, and relative humidity. The establishment is required to validate

that the entire HACCP system is operating as intended and to verify that it is producing

a safe and wholesome product on an ongoing basis.

Complete failure to document critical limit monitoring has also contributed to the recall of

cooked poultry products in the past due to a processing defect (RC-009-2017). Such a

failure highlights the importance of accurate records documenting the implementation of

the critical operating parameters to support the production of safe products.

Corrective Actions under HACCP Cooking Deviations

Cooking deviations occur when an establishment fails to meet its cooking CCP critical

limit or cooking humidity option. Common causes for cooking deviations include

product overlap, power failures, or breakdown of cooking equipment. The HACCP

regulations require establishments to take corrective actions in response to these

deviations, regardless of whether the cooking process is addressed through a CCP or

prerequisite program. Corrective actions include ensuring no product that is injurious to

health or otherwise adulterated because of the deviation enters commerce and

supporting product disposition decisions (9 CFR 417.3(a) and (b)).

When cooking is addressed through a CCP, establishments are required to determine

the cause of all cooking deviations, no matter how small (9 CFR 417.3(a)(1)), and

ensure measures are established to prevent recurrence (9 CFR 417.3(a)(3)). Continual

or repetitive process deviations from the critical limit demonstrate that the establishment

is unable to control its process.

When cooking is addressed through a prerequisite program, establishments are

required to reassess their HACCP system to determine whether the newly identified

deviation or unforeseen hazard should be addressed and incorporated into the HACCP

plan (9 CFR 417.3(b)(4)). Also, an establishment may not be able to continue to

support the decision in its hazard analysis that pathogens are not reasonably likely to

occur, if it has continual or repetitive deviations from its cooking prerequisite program (9

CFR 417.5(a)(1)). For more information on evaluating product disposition after a

cooking deviation see Corrective Actions to Perform When a Cooking Deviation Occurs

(page 66).

FSIS Critical Operating Parameters for Cooking

(Time-Temperature Tables)

Establishments that cook products to achieve lethality by applying the time-temperature

combinations from this guideline need to consider the critical operating parameters that

may affect pathogen Log reductions, specifically:

• Come-up-time (CUT),

• Relative Humidity, and

• Endpoint Time-Temperature.

Additionally, establishments cooking poultry products need to consider product species

composition and fat content if applying FSIS cooking lethality guidance in the tables on

pages 37 and 38. The FSIS Cooked Poultry Rolls Options (page 39) apply to all poultry

products regardless of poultry species or fat content. For information about why product

species should be considered when applying cooking lethality guidance on pages 37

and 38 and not when applying the FSIS Cooked Poultry Rolls Options see page 36.

Come-Up-Time (CUT)

When applying one of the time-temperature tables from this guideline, an establishment

must also consider the heating CUT to be a critical operating parameter unless the

establishment can provide a science-based rationale why heating CUT does not need to

be addressed. For example, products that are fermented and then cooked to lethality

may control S. aureus outgrowth by lowering the pH following the degree-hour concept

as recommended in the American Meat Institute’s Good Manufacturing Practices for

Fermented Dry & Semi-Dry Fermented Sausathge Products and therefore would not

address CUT.

FSIS has developed a CUT Option that establishments may use to support its process

control of S. aureus growth, specifically ≤ 2-Log that also

prevents enterotoxin formation:

Come-Up-Time Option: Total time product temperature is

between 50 and 130°F is 6 hours or less.

NOTE: This CUT Option is only for products that were cooked to

lethality (including those cooked to lethality but classified as

NRTE under a heat treated, not fully cooked, not shelf-stable

HACCP plan). Please refer to the FSIS Stabilization Guideline for

Meat and Poultry Products for the Agency’s recommendations

regarding CUT in partially cooked products that do not receive a

full lethality. Please also refer to the product reclassification

guidance in the Listeria Guideline, Attachment 1.2 on pages 22-

23 and Appendix 1.2 on pages 28-29.

FSIS is aware that establishments preparing some products (e.g.,

ham or beef brisket) may not be able to follow FSIS’s Come-Up-

Time Option above because of the thermodynamics of the

heating process. Therefore, FSIS identified long CUT as a

Scientific Gap since support does not exist for many common

processes (page 48). Additionally, alternative support for certain

long CUT processes have been included in Attachment A1.

Customized Processes and Alternative Lethality Support (page

55).

Temperatures referred to in FSIS’s Come-Up-Time Option above,

are internal temperatures. However, establishments may monitor

surface temperatures during CUT, if the establishment provides

support the product is intact and processed so pathogens have

not been introduced below the product surface. Non-intact

product temperatures should be taken internally at the center of

KEY DEFINITIONS

Come-up-time refers to

the

amount of time product

temperature is between 50-

130°F while heating.

Intact refers to products

where the interior remains

protected from pathogens

migrating below the

exterior/outside (such as

beef brisket or a picnic

shoulder that is not injected

or vacuum tumbled).

Non-Intact refers to

products where pathogens

may have been introduced

below the surface.

Examples include products

that have been

mechanically tenderized

(including those that have

been injected with

marinade or solution) or

vacuum tumbled.

the product (see Key Definitions panel to the right for an explanation of intact and non-

intact products). Establishments should also take temperatures at the center of the

product for products such as deboned and rolled hams where a portion of the product is

rolled or folded over and pathogens may be internalized.

NOTE: FSIS time-temp tables list internal endpoint temperatures during cooking. It is

not supportable to use surface temperature to address endpoint temperature. FSIS is

only making this recommendation for its CUT option.

Relative Humidity

FSIS time-temperature tables use relative humidity as a critical operating parameter to

ensure moist cooking and adequate surface lethality. An establishment that uses the

FSIS time-temperature tables to support its cooking process must address humidity,

unless it meets one of the criteria listed in Situations when Humidity is Not Needed

(page 31) or provides additional support for why

humidity would not be needed in its process to ensure

lethality on the product surface. FSIS has included

specific relative humidity options for use with the time-

temperature tables (page 26). Additional resources

for determining which relative humidity option to adopt

are included in Relative Humidity Resources (page

28).

NOTE: FSIS is aware that some establishments may

not be able to use FSIS’s humidity options because of

the nature of the cooking process. Examples include

products cooked for short times at high temperatures

(e.g., for meat balls or chicken tenders) or other

processes that do not allow the use of humidity (e.g.,

barbecue products cooked under dry heat including

those cooked in smokehouses or open pits). Please

refer to Scientific Gaps Identified by FSIS (page 41).

Selection of the proper relative humidity option

depends on the endpoint time-temperature. Products

cooked to endpoint time-temperatures of at least

145°F plus the dwell time, may apply any of the

relative humidity options in Table 1. Critical

Operating Parameters for FSIS Humidity Options.

Key Question

Question: An establishment cooks a brisket to full lethality but realizes the smoke

coloring is too light and wants to recook it to deepen the color. Can the establishment

apply a new 6 hour CUT for the second cook?

Answer: Yes. Once a product achieves a lethal time-temperature combination, the

allowed CUT is reset for the next cook. If the establishment chooses to recook the

product, it may apply a new 6 hour CUT limit (page 23). However, if the product did not

achieve a lethal time-temperature combination during the first cooking process, the CUT

does not start over. The establishment should support the total time product temperature

is between 50 and 130°F is 6 hours or less. Please review Attachment A2. Cooking

Deviations subsection Missed Time-Temperature Parameter (page 67) for additional

information.

KEY DEFINITIONS

Maintaining humidity means

keeping the humidity at the same

level throughout the cooking

process. If the humidity drops

during the cooking process, the

establishment will need to

provide additional support for the

safety of the product

A sealed oven is generally

defined as one in which the

smokehouse doors and oven

dampers are closed to prevent

moisture loss.

The cooking time includes the

time the product is placed in the

heated oven (including surface

preparation and color setting)

until the product reaches the

desired lethality time-

temperature combination (also

referred to as the “lethality

treatment”).

However, products cooked to an endpoint less than 145°F, should select Option 3 or 4

in Table 1. Critical Operating Parameters for FSIS Humidity Options depending on total

cooking time.

NOTE: To be most effective, humidity needs to be applied during the lethality

treatment, before drying. Using this guideline to support lethality processes in which

the drying step comes before the moist cooking step (e.g., country-cured ham)

creates a vulnerability in the establishment’s HACCP system. Establishments using

this guideline for these processes should read Attachment A6. Cooking Country-

Cured Hams (page 90) for recommendations to reduce this vulnerability, such as

measuring water activity after cooking to verify it increases and the product surface

was rehydrated during cooking.

To ensure that adequate humidity is attained, the establishment should monitor

the humidity throughout the lethality treatment. The process should be monitored

using wet and dry bulb thermometers (used to determine relative humidity) or a humidity

sensor. FSIS recommends that establishments monitor relative humidity for every lot or

batch of product produced.

Table 1. Critical Operating Parameters for FSIS Humidity Options

CRITICAL OPERATING PARAMETERS

Relative Humidity

Endpoint

Temperature

Cooking

Time

OPTION 1:

The relative humidity of the oven is

maintained by continuously introducing

steam for 50 percent of the cooking time,

or 1 hour, whichever is longer.

≥145°F +

dwell time

≥1 hour

OPTION 2:

The relative humidity of the oven is

maintained by a sealed oven for at least

50 percent of the total cooking time, or 1

hour, whichever is longer.

≥145°F +

dwell time

≥1 hour

OPTION 3: The relative humidity of the oven is

maintained at 90 percent or above for at

least 25 percent of the total cooking time,

or 1 hour, whichever is longer.

Any ≥1 hour

OPTION 4:

The relative humidity of the oven is

maintained at 90 percent for the entire

cooking time.

Any

Key Question

Question: To follow the sealed oven or steam injection options, must establishments

achieve a specific relative humidity?

Answer: No. Establishments do not need to achieve a specific relative humidity level in

the oven if they are following the steam injection or sealed oven options in this guideline

as their scientific support. Based on expert opinion, the 2014 FSIS Jerky Guideline

recommended that establishments producing jerky that monitor relative humidity try to

achieve a wet bulb temperature of at least 125-130°F for 1 hour or more along with a

corresponding dry bulb temperature needed to achieve at least 27-32% relative humidity

or more. However, the Jerky Guideline also noted, achieving a wet bulb temperature of at

least 125-130°F and at least 27-32% relative humidity for 1 hour or more is not adequate

on its own to support that the process is being implemented consistently with FSIS

Humidity Options. Rather, establishments should ensure that all critical operating

parameters described in this guidance are met. Relative Humidity Resources (page 28

contains specific guidance for how to implement Option 1 steam injection and Option 2

sealed oven in a validated HACCP system. In addition, establishments should not apply

the wet-bulb and relative humidity recommendations in the Jerky Guideline to other

products without additional support.

Current Support for FSIS Relative Humidity Options

Although the research cited as the basis of FSIS guidance dates as far back as 1978,

newer research by McMinn et al., (2018) supports that the time-temperature parameters in

FSIS’s cooking guidance achieves sufficient reductions of Salmonella. This research by

McMinn et al. (2018) was conducted with product cooked in vacuum-sealed bags

supporting the importance of cooking in a high moisture environment. While newer

research has not been conducted to validate the sealed oven and steam injection relative

humidity options, research does continue to support the importance of moisture during

cooking. For example, Mann and Brashears (2007), support the need for at least 30%

relative humidity during cooking of roast beef. Based on FSIS knowledge of

establishments’ processes through its verification activities, the Agency believes when the

oven is sealed, or steam is introduced, at least 30% relative humidity is maintained,

suggesting that these practical recommendations result in adequate relative humidity.

The Agency is also not aware of any establishments that have had Salmonella positives or

been associated with a salmonellosis outbreak when following FSIS temperature, time,

and relative humidity guidance while using effective monitoring procedures.

*Relative humidity (RH) is 90% or higher for at least 25% of the total cooking

time, or 1 hour, whichever is longest.

**RH is maintained for

50% of the cooking time, or 1 hour, whichever is

longest

For more information,

refer to FSIS Relative Humidity Options on page 25.—

wouldn’t it be good to put the information together?

Additionally,

the following information in the FSIS Jerky Guideline can be

useful when deciding which humidity option to adopt:

 Instructions for making your own wet bulb (reprinted with

permission from the University of Wisconsin, page 49); and

 An example of a time-temperature recorder chart to support the

option of continuously injecting steam (page 53).

Relative Humidity Resources

The following flow chart contains specific guidance for how to choose a humidity option

and the resources on the next two pages are designed to help establishments

implement Option 1 steam injection and Option 2 sealed oven in a validated HACCP

system.

Flow Chart to Choose a Humidity Option

*Relative humidity (RH) is 90% or higher for at least 25% of the total cooking

time, or 1 hour, whichever is longest.

**RH is maintained for 50% of the cooking time, or 1 hour, whichever is

longest

For more information, refer to FSIS Relative Humidity Options on page 26.

Additionally, the following information in the FSIS Jerky Guideline can be

useful when deciding which humidity option to adopt:

• Instructions for making your own wet bulb (reprinted with

permission from the University of Wisconsin, page 49); and

• An example of a time-temperature recorder chart to support the

option of continuously injecting steam (page 53).

Specific Guidance for Using the “Sealed Oven” Option

To support the use of the sealed oven option for addressing relative humidity, FSIS

recommends establishments follow all 4 steps below:

1) Maintain documentation that supports that the product achieves an internal

product temperature equal to or greater than 145°F (plus the required dwell time)

from the FSIS time-temperature tables. Such documentation could include:

a. Records of internal product temperature and time held at that temperature, (if applicable); or

b. Records of the oven or smokehouse temperature in place of internal product temperature

provided that the establishment has a consistent product and process and has sufficient

data correlating the oven temperature selected with the internal product temperature in the

scientific support;

2) Maintain documentation that supports that the oven dampers are closed for at

least one hour or 50% of the cooking time, whichever is longer. Such

documentation could include:

a. Records from a computerized system that document the time at which the oven dampers

were open and were closed; or

b. Records, made manually, of the times at which the oven dampers were open and closed;

c. Records demonstrating that the relative humidity level in the oven is maintained for at least

one hour or 50% of the cooking time, whichever is longer (e.g., by use of dry and wet bulb

thermometers to calculate the relative humidity or use of a humidity sensor that provides a

direct measurement) with correlation data supporting a relationship between the relative

humidity level in the oven and the time at which the oven dampers were open and closed;

3) Maintain documentation that supports that when the oven dampers are closed,

humidity is maintained in the ovens. Such documentation could include:

a. Records demonstrating the relative humidity level in the ovens is maintained (e.g., by use of

dry and wet bulb thermometers to calculate the relative humidity or use of a humiditysensor

that provides a direct measurement), or

b. Data gathered during the initial validation period along with ongoing verification that

demonstrate that the relative humidity in the oven is maintained while the dampers are

closed; and

4) Perform routine checks to ensure the oven dampers are properly working along

with a maintenance program that includes periodic monitoring to ensure oven

seals are intact and functional, and that when the oven dampers are closed, a

tight seal is obtained.

A tight seal is one that prevents a significant loss of humidity. FSIS acknowledges

that a small amount of smoke or vapors might be seen escaping the smokehouse

even when a tight seal is obtained. FSIS also recommends establishments

consider whether there are other openings, particularly in older smokehouses, such

as drain valves or air intake valves that need to be closed to ensure that a seal is

obtained. Finally, some older ovens may have a stack or other opening that cannot

be closed. For those establishments with older ovens that cannot be completely

closed, the sealed oven method should not be used. However, the establishment

may choose to close the parts of the oven it can, then add moisture in the system

either by continuouslyintroducing steam, or by using another validated method.

Specific Guidance for Using the “Continuously Introducing Steam” Option

To support the use of the continuously introducing steam option for addressing relative

humidity, FSIS recommends establishments follow all 3 steps below:

1) Maintain documentation that supports that the product achieves an internal product

temperature equal to or greater than 145°F (plus the required dwell time) from the

FSIS time-temperature tables. Such documentation could include:

a. Records of internal product temperature and time held at that temperature, (if

applicable); or

b. Records of the oven or smokehouse temperature in place of internal product

temperature provided that the establishment has a consistent product and process and

has sufficient data correlating the oven temperature selected with the internal product

temperature in the scientific support;

2) Maintain documentation that supports that steam is continuously introduced for at

least one hour or 50% of the cooking time, whichever is longer. Such documentation

could include:

a. Records from a computerized system that contains the time at which the steam is turned

on and off; o r

b. Records, made manually, of the times at which the steam is turned on and off; or

c. Records demonstrating the relative humidity level in the oven is maintained for at least

one hour or 50% of the cooking time, whichever is longer (e.g., by use of dry and wet

bulb thermometers to calculate the relative humidity or use of a humidity sensor that

provides a direct measurement), along with correlation data supporting a relationship

between the relative humidity level in the oven and the time steam is turned on or a letter

from the manufacturer stating that when the relative humidity is rising, it is because of

live steam injection; and

3) Maintain documentation that supports that when steam is injected, humidity is

maintained in the ovens. Such documentation could include:

a. Records demonstrating the relative humidity level in the ovens is maintained (e.g., by

use of dry and wet bulb thermometers to calculate the relative humidity or use of a

humidity sensor that provides a direct measurement), or

b. Data gathered during the initial validation period along with ongoing verification which

demonstrates that the relative humidity in the oven is maintained while steam is being

injected.

NOTE: The “continuously introducing steam” option refers to the use of live steam.

This option may also apply to establishments that spray water onto hot heating

elements, which creates steam that in turn produces humidity in the smokehouse.

“Continuous” does not mean that the steam is injected for at least one hour during

one stage. Rather, steam could be injected during specific stages or time intervals

during the lethality (cooking) treatment as long as the total amount of time the steam

is introduced adds up to at least one hour or 50% of the cooking time, whichever is

longer. Furthermore, the establishment may turn the steam on and off throughout the

cooking time when the target humidity is reached.

Key definitions

Convective

heating

Conduction

Radiant heating

Conductive Heating:

Heat is transferred

directly into the food

product by physical

contact

with the heating

medium (e.g. heating

product on a

skillet).

Radiant Heating:

Heat

is transferred

directly

into the food product

radiant energy without

the movement of air or

physical

contact

between

the source

and

the food. Two common

examples:

Radiant

energy from the sun

warms Earth across

the

vacuum of space, or a

flame emits radiant

energy

to heat food

product in certain

rotisserie ovens.

Various

forms

of radiant

energy also include

gamma

rays, electron

beams, x

-rays, and

microwaves.

Establishments that use processes that match one of

these situations do not need to monitor relative

humidity as a critical operating parameter in their

cooking procedure.

Situations when Humidity is Not Needed

FSIS recognizes two situations when humidity does not need to be

addressed to ensure adequate lethality:

1. When moisture is inherently maintained; or

2. When product is cooked using direct heat.

Relative humidity does not need to be addressed when moisture is

inherently maintained around the product. Examples of these

types of processes include, but are not limited to:

• Completely immersing the meat or poultry product in a

liquid cooking medium throughout the entire cooking

process;

o E.g., unbagged, in water

• Cooking the product in a sealed, moisture impermeable bag

(e.g., cook-in-bag meat or poultry);

o Cook-in-bag products may be eligible to be labeled

as “pasteurized” (see Attachment A3. When can

Products be Labeled as Pasteurized? page 81).

• Cooking product in a casing that holds moisture (e.g.,

natural casings, cellulose casings, collagen casings, fibrous

casings and plastic casings (sometimes called "synthetic"

casings)).

o See the question box on page 33 for information on

cooking using natural casings.

• Heating meat or poultry products that weigh 10 pounds or

more in an oven maintained at 250°F (121°C) or higher

throughout a process achieving one of the time-

temperature combinations in this guideline.

NOTE: Humidity is not needed for products that weigh 10 pounds

or more in an oven maintained at 250°F (121°C) or higher

because they have a low surface to mass ratio (Goodfellow and

Brown, 1978). Therefore, the surface dries out slower than

smaller products and Salmonella is less likely to become heat

tolerant.

KEY DEFINITIONS

During

convective

heating

the food

product is indirectly

heated by the

movement of hot air.

This

type of heating

typical for

solid foods

cooked in a smoke

house oven.

Conductive Heating:

Heat is transferred

directly into the food

product by physical

contact with the

heating

medium (

e.g.,

heating product in a

skillet).

Radiant Heating:

Heat is transferred

directly into the food

product by radiant

energy without the

movement of air or

physical contact

between the source

and the food.

Two

common examples:

are

(1) broiling

where

food is exposed to

direct,

intense

radiant

heat or (2) certain

types of rotisserie

ovens where a flame

emits radiant energy

to heat food.

Forms of radiant

energy also include

gamma

rays,

electron

beams, and x-rays.

Relative humidity also does not need to be addressed for processes that apply direct

heat via conduction or radiant heating. Unlike convective heating, which uses moving

hot air or steam to heat the product (e.g., smoke house ovens, spiral ovens,

impingement ovens), direct heating (e.g., conductive heating, radiant heating) puts the

product in direct contact with the heating medium. Direct heat ensures the product

surface quickly reaches lethality temperatures before bacteria can develop heat

tolerance due to the product’s surface

quickly drying out.

Examples of direct heat include:

• Grill.

• Broil (exposure to direct, intense

radiant heat).

• Heating coil,

• Flame.

• Certain rotisserie ovens that cook the meat or poultry over the heat source

resulting in a product with a grilled quality.

NOTE: Direct heat cooking is rarely used in conjunction with rotisserie cooking. Indirect

heat cooking is most often used because it allows the meat or poultry to cook slowly

and evenly, which is the primary purpose for using a rotisserie for cooking. For indirect

heat cooking, the rotisserie is positioned in front of or next to the heat source and it is

the heated air that cooks the product (convection cooking).

Cooking meat patties per 9 CFR 318.23 does not include humidity considerations

because these products were assumed to be cooked with direct heat such as a grill,

heating coil, or flame. Meat patties cooked per 9 CFR 318.23 do not need to address

relative humidity. For the definition of a patty see 9 CFR 318.23.

NOTE: Products cooked using microwave cooking methods that are not designed to

control relative humidity is considered a Scientific Gap because these common cooking

processes can’t achieve the relative humidity options included in this guideline;

however, there is a lack of research to support alternative parameters. For the critical

operating parameters in this guideline that can be used for these processes, if using

FSIS guidance as scientific support, see Table 5. Scientific Gaps where Critical

Operating Parameters From Older Guidance May be Used page 44.

How is indirect heating identified?

Moving air or steam is a sign of convective (indirect)

heating. Ovens that use moving air to heat the

product need to address relative humidity to ensure

sufficient Log reductions for pathogens are achieved.

Do Products Cooked in Natural Casings Made from Animal Gastrointestinal

Tracts Need to Address Relative Humidity?

No, establishments using FSIS cooking guidance as support do not need to address

relative humidity for products that are cooked in a natural casing, including products

that are cooked and then dried.

Natural casings made from animal gastrointestinal tracts are typically considered

permeable and many establishments take advantage of their permeability to produce

dried products or smoked products. However, depending on how they are used, the

permeability of natural casings may be reduced. Most cooking processes likely reduce

the permeability of natural casings early in the process so that humidity around the

product is inherently maintained throughout the remainder of cooking and does not

have to be added or monitored. According to Sebranek, (2010), establishments will

apply smoke early in the process while the casing is still moist and permeable to the

smoke. Prior to smoke application, the casing surface should be "tacky" or "sticky."

After smoke deposition and color development, further cooking denatures the proteins

in the casing reducing permeability to the point that later cooking can be applied without

great moisture loss from the product. Proteins in natural casings begin denaturing at

126°F (Tornberg, 2005). However, most drying processes use lower temperatures and

address relative humidity to maintain casing permeability so that moisture can

evaporate from the product during drying.

Although most cooking processes likely result in reduced permeability of natural

casings early in the cooking process, little research has been performed to study the

critical operating parameters that impact the reduction of permeability such as the

length of the initial smoke application step, cooking temperature, total cooking time, use

of steam, size of casings, composition of sausage batter, etc. For this reason, FSIS

has posted a research study on its website to “Determine if natural casings maintain

sufficient moisture to ensure product lethality using Appendix A time and temperature

tables.” Without this additional research, the Log reduction of Salmonella is less

certain if meat products in natural casings are cooked using one of the time-

temperature parameters in this FSIS cooking guidance without following one of the

humidity options. So, while FSIS has indicated establishments using FSIS cooking

guidance as support do not need to address relative humidity for products that are

cooked in a natural casing, if an establishment uses one of the time-temperature

parameters in FSIS cooking guidance without addressing relative humidity has a

positive Salmonella test result through FSIS or its own testing, it should, as part of

corrective actions, provide evidence that lack of relative humidity was not the cause. In

addition, if research is completed and data becomes available that indicates relative

humidity needs to be addressed when products are cooked in a natural casing, FSIS

may change its recommendation.

NOTE: As described in the Products and Processes Not Covered by This Guidance,

this guideline is not appropriate support for lethality of a process that relies on drying

alone or to support a process where the drying step comes before a cooking step that

does not apply humidity or does not apply humidity during cooking at sufficient levels to

rehydrate the product surface during the cooking step under dry conditions.

Endpoint Time-Temperature

FSIS time-temperature tables in this guideline (Meat Table, the 5-Log Table, and the

Poultry Time-Temperature Tables) list internal product temperatures and the

corresponding dwell times needed to achieve specific Log reductions of Salmonella.

These tables may be used as scientific support to ensure that the process meets

regulatory requirements (see General Considerations for Designing HACCP Systems to

Achieve Lethality by Cooking, page 18).

NOTE: To apply an alternative lethality and use Table 6. Time-Temperature

Combinations for Meat Products to Achieve a 5-Log Reduction (page 59), an

establishment must provide additional documentation showing that the product meets

the performance standard (if applicable) and that potentially hazardous pathogens have

been controlled (see Attachment A1. Customized Processes and Alternative Lethality

Support subsection: Supporting an Alternative Lethality Target (e.g., 5-Log) on page

57). The support should demonstrate the incoming load of Salmonella is lower than

FSIS estimated based on its baseline studies, and therefore, a lower reduction from

cooking would result in no viable Salmonella in the finished product.

Key Question

Question: When an establishment decides to use a FSIS time-temperature table (i.e., the

5-Log Meat Table, 6.5-Log Meat Table, or the 7.0-Log Poultry Time-Temperature Tables)

from this guideline as its scientific support for its cooking/lethality step, can the

establishment use the entire table as its critical limit in its HACCP plan?

Answer: Yes, the establishment can use the entire table to comply with 9 CFR

417.2(c)(3). The establishment needs to make a sound determination and support its

decision in selecting and monitoring the time-temperature parameter(s) it uses for its

production (9 CFR 417.5(a)(2)). In addition, establishments must collect in-plant data for at

least one product from each HACCP category demonstrating the implementation of the

critical operational parameters of the scientific support (9 CFR 417.4(a)(1)). At a minimum,

the establishment will need to demonstrate that it is able to consistently meet a specific

time-temperature from the table identified during the initial validation period to support the

cooking/lethality process is validated (9 CFR 417.4(a)(1)).

Table 2. Time-Temperature Combinations for Meat Products to Achieve Lethality

Temperatures stated are the minimum internal temperatures that must be met in all parts of the

meat product for the total dwell time listed.

An establishment must ensure both time and

temperature parameters are met to use this table to support its process achieves the Log

reduction target. Relative humidity

and heating come-up-time (CUT)

are also critical

operating parameters when using this table. (See pages 37 and 38 for poultry endpoint time-

temperature tables).

The required Log reductions are achieved instantly (0 seconds) when the internal temperature

of a cooked meat product reaches 158°F or above.

Time-Temperatures ≥ 145°F (in blue square) are eligible for FSIS Relative Humidity Options 1

and 2. All time-temperatures may apply FSIS Relative Humidity Options 3 and 4 (page 26).

FSIS recommends limiting the total time product temperature is between 50 and 130°F to 6

hours or less (see page 23).

Additional Critical Operating Parameters for Poultry Products

The following are additional critical operational parameters that should be considered

when cooking poultry products using FSIS newer guidance in the poultry time-

temperature tables.

Note: The older poultry recommendations for Cooked Poultry Rolls on page 39 apply

regardless of species or fat because these were not considered critical operating

parameters at the time the recommendation was developed. FSIS is not aware of any

outbreaks or food safety incidents as a result of applying these recommendations to

products of varying species or fat level.

Product Species

Generally, FSIS accepts that research for an intervention’s effectiveness on one

species of poultry (i.e., chickens, turkeys, ducks, geese, ratites, and squabs) can be

applied to another species of poultry without additional support (FSIS Directive 5000.6,

Performance of the Hazard Analysis Verification Task). However, research by Juneja et

al. (2001a) demonstrated that in cooking processes, Salmonella heat tolerance depends

on the poultry species. Therefore, when FSIS developed its time-temperature tables for

poultry it developed two unique poultry time-temperature tables: one for chicken (page

37), another for turkey (page 38).

When making poultry products containing poultry species other than chicken or

turkey, or products made with a mixture of poultry species, FSIS recommends

selecting an endpoint temperature, then using the longest dwell time recommended for

the product fat content and endpoint temperature in either the chicken or turkey table.

Comparing the tables and using the longest recommended dwell time ensures the

HACCP system is designed to address the worst-case scenario for Salmonella survival

in the product. Products that are a mixture of poultry and meat must achieve a 7-Log

reduction of Salmonella (see Key Question on page 19).

Fat Content

In the presence of fats, the heat tolerance of some microorganisms generally increases

(Jay et al., 2000). This is sometimes referred to as fat protection and is presumed to

increase heat tolerance by affecting cell moisture. Juneja et al., (2001b) showed that

higher fat levels in beef result in increased heat resistance of Salmonella, which is in

agreement with publications regarding other food borne pathogens (Line et al., 1991;

Ahmed et al., 1995). The Poultry Time-Temperature Tables (pages 37 and 38) provide

establishments with time-temperature combinations that can be used to cook chicken

and turkey products with different fat levels.

A 7-Log reduction of Salmonella is achieved instantly at internal temperatures in which the holding time is 0 seconds (0 sec.).

Time-Temperatures ≥ 145°°F (in blue square) are eligible for FSIS Relative Humidity Options 1 and 2. All time-temperatures may apply FSIS

Relative Humidity Options 3 and 4 (page 26).

FSIS recommends limiting the total time product temperature is between 50 and 130°F to 6 hours or less (see page 23).

Table 3. Time-Temperature Combinations for Chicken Products to Achieve Lethality

Times for given temperatures and fat levels that are needed to obtain a 7-Log reduction of Salmonella in chicken products.

As described on page

23, relative humidity

and heating come-up-time (CUT)

are critical operating parameters when using this table.

Table 4. Time-Temperature Combinations for Turkey Products to Achieve Lethality

Times for given temperatures and fat levels that are needed to obtain a 7-Log reduction of Salmonella in turkey products.

As described on page

23, relative humidity

and heating come-up-time (CUT)

are critical operating parameters when using this table.

A 7-Log reduction of Salmonella is achieved instantly at internal temperatures in which the holding time is 0 seconds (0 sec.).

Time-Temperatures ≥ 145°°F (in blue square) are eligible for FSIS Relative Humidity Options 1 and 2. All time-temperatures may apply FSIS

Relative Humidity Options 3 and 4 (page 26).

FSIS recommends limiting the total time product temperature is between 50 and 130°F to 6 hours or less (see page 23).

Cooked Poultry Rolls Options

FSIS recommends establishments use the options in the Poultry Time-Temperature

Tables (page 37 and 38) (which include dwell times at 160°F that vary based on fat

content and species) because they have been validated with updated research to

address species and fat content as critical operating parameters to ensure adequate

Log reductions of Salmonella. However, FSIS is including the two older options below

for cooking poultry rolls and other poultry products because they still may be used by

some establishments. Applying the cooked poultry rolls options below may achieve the

same Log reductions as the time-temperature combinations in the Poultry Time-

Temperature Tables, particularly when applied to a lean product, because the product

may be maintained at 160°F for the recommended dwell times (between 13.7 to 26.9

seconds depending on species and fat) during the time it takes to complete temperature

monitoring. Regardless, FSIS recommends establishments monitor the dwell time in

the Poultry Time-Temperature Tables as opposed to relying on the older guidance for

cooked poultry rolls below to better assure safety.

The options below can be applied to any poultry product (not just cooked poultry rolls)

regardless of fat content or poultry species. However, if FSIS collects a RTE sample

that is positive for Salmonella or if the establishment is implicated in a food safety

investigation related to Salmonella (i.e., is associated with reports of illness or

outbreak), FSIS will review and determine the adequacy of the establishment’s required

corrective actions (taken under 9 CFR 417.3), to address process deviations. The

establishment will need to show FSIS that inadequate lethality was not the root cause of

the process deviation if it wants to continue to follow the cooked poultry rolls options.

To use a cooked poultry rolls option, the establishment must address all critical

operating parameters for cooking identified in this guideline (other than species or fat),

including relative humidity (page 26) and CUT (page 23).

1. Cooked poultry rolls and other cooked poultry products must reach an internal

temperature of at least 160°F (instantaneous) during the cooking process.

2. Cured and smoked poultry rolls and other cured and smoked poultry must

reach an internal temperature of at least 155°F (instantaneous) during the

cooking process.

Key Question

Question: Can establishments that produce poultry products with higher than 12% fat use values

for 12% fat in the Poultry Time-Temperature Tables?

Answer: Yes. The time-temperature combinations listed in the tables for poultry products with

12% fat can be used for products with higher percentages of fat and for products with unknown fat

content. These time-temperature combinations will achieve sufficient lethality as long as adequate

humidity (FSIS Relative Humidity Options page 26) is applied during the process.

Resources for Customized and Alternative Support

FSIS recognizes that not all meat and poultry products can be cooked using the FSIS

critical operating parameters (humidity, CUT and endpoint time-temperature) included in

this guideline. To assist establishments in cooking their products, FSIS has identified

additional resources which may provide scientific support for a specific process or part

of a process. Attachment A1. Customized Processes and Alternative Lethality Support

includes information on the following:

• Alternative Lethality Target: Under certain circumstances and with additional

support, establishments may be able to use an alternative lethality target (e.g. 5-

Log). See Attachment A1. Supporting an Alternative Lethality Target, page 57 of

this guideline.

• Journal Articles: Establishments could identify a published journal article which

shows a specific process meets the performance standard and use this as

scientific support. See Attachment A1. Common Topics and Journal Articles

Used for Alternative Support page 60 of this guideline.

• Customized Cooking Schedule: Establishments may design a customized

cooking plan using validated microbial models. See Attachment A1. Predictive

Microbial Modeling for Critical Operating Parameters, page 62 of this guideline.

• Challenge Studies: Establishments could conduct challenge studies to

determine if their proposed process would meet the performance standard. See

Attachment A1. Designing Challenge Studies for Cooking, page 63 of this

guideline.

In addition to information for developing customized critical operating parameters, this

guideline contains additional resources, listed below, to address common questions and

issues establishments may have regarding cooking of meat and poultry products.

• Pasteurized Label: Establishments may be able to label their cooked meat or

poultry product as “Pasteurized.” See Attachment A3. When can Products be

Labeled as Pasteurized?, page 81 of this guideline.

• Common Sources of Salmonella: Salmonella contamination may occur on

cooked products for a variety of reasons. For information on sources of

Salmonella contamination and Best Practices to implement to address it, see

Attachment A4. Sources of Salmonella Contamination in RTE Products and Best

Practices to Address It page 82 of this guideline.

• Ready-to-eat (RTE) Self-Assessment Tool: FSIS has included a self-

assessment tool that establishments can use to identify areas in their process

where they could improve Salmonella control. See Attachment A5. RTE

Salmonella Self-Assessment Tool page 87 of this guideline.

Scientific Gaps Identified by FSIS

FSIS has identified several common cooking processes that can’t achieve the critical

operating parameters included in this guideline. FSIS encourages establishments to

conduct challenge studies when other support is not available (page 63). However, the

Agency realizes it may not be cost effective for establishments to conduct individual

challenge studies for commonly produced meat and poultry products. To address these

common processes, which lack readily available scientific support, FSIS has identified

and communicated scientific gaps and is working to facilitate filling these gaps. FSIS

posted research priorities on its website to communicate clear research needs with

USDA Agricultural Research Service (ARS) and academic researchers. As additional

data becomes available, FSIS will update the recommendations for these scientific gaps

with the latest available scientific support.

An establishment producing products using processes that fall under an identified

scientific gap may use the critical operating parameters in this guideline as scientific

support (see Table 5. Scientific Gaps where Critical Operating Parameters From Older

Guidance May be Used page 43). Table 5 also describes specific vulnerabilities with

using the gaps as scientific support and recommends steps to reduce the vulnerabilities.

In addition to those specific vulnerabilities, FSIS has the following concerns with

establishments continuing to process products using the critical operating parameters in

Table 5:

• Use of these critical operating parameters represents a vulnerability because

these processes have not been validated to address all hazards of concern. The

original research used to develop these critical operating parameters was

performed on only the few products covered by the performance standard to be

included in the 1999 version of Appendix A [64 FR 732].

• If a process deviation occurs for a process that is included as a scientific gap, it is

unlikely an establishment would be able to identify adequate support for product

safety without performing product testing.

• If FSIS or the establishment collects a ready-to-eat (RTE) sample that is positive

for Salmonella, or the establishment is implicated in a food safety investigation

related to Salmonella (i.e., is associated with reports of illness or outbreak), FSIS

would verify, as part of the corrective actions (9 CFR 417.3), that the

establishment can support inadequate lethality was not the root cause, if it wants

to continue to use the older recommendation.

• As additional data becomes available, FSIS will change the recommendations for

processes that fall under one of these scientific gaps.

NOTE: Scientific gaps only affect very specific products and processes. Process

deviations and malfunctioning equipment are NOT scientific gaps. Additionally,

Products and Processes Not Covered by this Guideline would NOT be adequately

supported by the critical operating parameters listed in Table 5.

Scientific gaps are processes which have not been validated to achieve

sufficient lethality and to address all potential hazards during cooking, but

establishments may continue to use this guidance as support to allow

additional time for research to be conducted and gaps filled.

FSIS will update this guideline as more research becomes available and new options

can be developed.

NOTE: Scientific gaps only affect very specific products and processes. Process deviations and malfunctioning equipment

are NOT scientific gaps. Products and Processes Not Covered by this Guideline would NOT be adequately supported by

the critical parameters listed in scientific gaps (Table 5).

Table 5. Scientific Gaps where Critical Operating Parameters From Older Guidance May be Used

Gap

Examples of

Products

1999 Critical

Operating

Parameters

Vulnerability with Continuing to Follow 1999

Parameters

1. Products cooked for short

times at high temperatures that

cannot maintain 90% humidity per

Option 4 and do not meet the

Situations when Humidity is Not

Needed (page 31).

Processes that meet this gap

include those in which product

is:

• Cooked for less than 1 hour, at

dry bulb oven temperatures

above 212°F.

NOTE: Above 212°F the

maximum relative humidity

decreases as the temperature

increases making it impossible to

achieve 90% relative humidity in

the oven regardless of the amount

of moisture present.

Cooking

meatballs or

poultry tenders

using

impingement,

spiral, and

steam-injected

inline ovens.

NOTE: Jerky

products are not

included under

this gap. There

are many

validated

lethality

processes

available for

jerky products.

Apply FSIS time-

temperature tables

(pages 35, 37, 38),

addressing all critical

operating parameters

(page 23) except

relative humidity.

NOTE: Relative

humidity does not

need to be

addressed for

products cooked in

completely immersed

in water (page 31).

These parameters may allow the surface of the

product to dry out during cooking. Lack of humidity

can cause pathogens to develop heat tolerance

and allow them to survive the heating process. In

addition, shorter cooking processes allow for

limited additional lethality during the heating come-

up time (sometimes called cumulative or integrated

lethality) which reduces the safety margin the

process provides.

To minimize these vulnerabilities, an establishment

may choose to implement, validate, and monitor as

part of the HACCP system, any of the following to

ensure moist cooking and demonstrate surface

lethality:

o Wet-bulb temperature.

o Dew point temperature.

o Percent moisture by volume.

o Increase dwell time or endpoint temperature.

o Increase total cooking time to increase

integrated lethality.

Or perform a challenge study (page 63).

Or conduct finished product testing for Salmonella

as part of on-going verification.

NOTE: Scientific gaps only affect very specific products and processes. Process deviations and malfunctioning equipment

are NOT scientific gaps. Products and Processes Not Covered by this Guideline would NOT be adequately supported by

the critical parameters listed in scientific gaps (Table 5).

Gap

Examples of

Products

1999 Critical

Operating

Parameters

Vulnerability with Continuing to Follow 1999

Parameters

2. Products cooked using

microwave cooking methods

that are not designed to control

relative humidity.

Processes that meet this gap

include those in which a meat or

poultry product is cooked using

a continuous or non-continuous

microwave oven.

Sliced bacon or

bacon chips

cooked using

continuous

microwave

ovens.

Apply FSIS time-

temperature tables

(pages 35, 37, 38),

addressing all critical

operating parameters

(page 23) except

relative humidity.

These parameters may not ensure surface

lethality. In addition, shorter cooking processes

allow for limited additional lethality during the

heating come-up time (sometimes called

cumulative or integrated lethality) which reduces

the safety margin the process provides.

To minimize these vulnerabilities, an establishment

may choose to implement, validate, and monitor,

any of the following to ensure moist cooking and

demonstrate surface lethality:

o Increase dwell time or endpoint temperature.

o Increase total cooking time to increase

integrated lethality.

Or perform a challenge study (page 63).

Or conduct finished product testing for Salmonella

as part of on-going verification.

NOTE: There is an additional vulnerability with

microwave cooking that the microwave energy

may not result in lethality of pathogens on

continuous belt surfaces (Taormina et al., 2011).

NOTE: Scientific gaps only affect very specific products and processes. Process deviations and malfunctioning equipment

are NOT scientific gaps. Products and Processes Not Covered by this Guideline would NOT be adequately supported by

the critical parameters listed in scientific gaps (Table 5).

Gap

Examples of

Products

1999 Critical

Operating

Parameters

Vulnerability with Continuing to Follow 1999

Parameters

3. Products cooked using

cooking methods that are not

designed to control relative

humidity other than microwave

ovens.

Processes that meet this gap

include those where product is

either:

• Cooked in ovens that are not

designed to be sealed (e.g., no

dampers) and designed

without a mechanism to

introduce steam.

• Barbecue products cooked

under dry heat to meet labeling

requirements (e.g., 9 CFR

319.80; and 9 CFR 381.164).

NOTE: This does not include

smokehouses where the gaskets

or dampers are broken or have

been removed.

Rotisserie

chicken

Products such

as pork butt or

beef brisket

cooked using

restaurant or

foodservice type

convection

ovens.

Barbecue

products cooked

under dry heat

including those

cooked in

smokehouses or

open pits.

NOTE: Jerky

products are not

included in this

gap. There are

many validated

lethality

processes

available for

jerky products.

Apply FSIS time-

temperature tables

(pages 35, 37, 38),

addressing all critical

operating parameters

(page 23) except

relative humidity.

NOTE: Relative

humidity does not

need to be

addressed for

products 10 pounds

or more cooked in an

oven at 250°F or

higher (page 31).

These parameters may allow the surface of the

product to dry out during cooking. Lack of humidity

can cause pathogens to develop heat tolerance

and allow them to survive the heating process.

To minimize this vulnerability, an establishment

may choose to implement, validate, and monitor,

any of the following to ensure moist cooking and

demonstrate surface lethality:

o Wet-bulb temperature.

o Dew point temperature.

o Percent moisture by volume.

Depending on the process, pans of water may be

added to increase moisture in the cooking

chamber.

Or perform a challenge study (page 63).

Or conduct finished product testing for Salmonella

as part of on-going verification.

NOTE: Scientific gaps only affect very specific products and processes. Process deviations and malfunctioning equipment

are NOT scientific gaps. Products and Processes Not Covered by this Guideline would NOT be adequately supported by

the critical parameters listed in scientific gaps (Table 5).

Gap

Examples of

Products

1999 Critical

Operating

Parameters

Vulnerability with Continuing to Follow 1999

Parameters

4. Other processes that may

inherently maintain relative

humidity around the meat and

poultry filling but cannot follow one

of the relative humidity options.

Processes that meet this gap

include those that involve:

• Use of an edible wrapping that

fully encloses a raw meat or

poultry filling before cooking.

Example wrappings include:

o dough,

o leaves, and

o edible rice paper.

NOTE: Products cooked in a

natural casing are not included in

this gap, since FSIS includes

natural casing in Situations when

Humidity is Not Needed (page 31).

Baked pasties,

empanadas,

pot-stickers, and

dumplings.

Apply FSIS time-

temperature tables

(pages 35, 37, 38),

addressing all critical

operating parameters

(page 23) except

relative humidity.

These parameters may allow the surface of the

filling or wrapping to dry during cooking. Lack of

humidity can cause pathogens to develop heat

tolerance and allow them to survive cooking.

To minimize this vulnerability, an establishment

may choose to implement, validate, and monitor as

part of the HACCP system, any of the following to

ensure sufficient lethality on the outside and inside

of the wrapped products:

o Cook filling first.

o Measure water activity of filling before and

after cooking to support moisture is inherently

maintained (water activity stays the same or

increases after cooking). FSIS recommends

establishments achieve the highest water

activity possible during cooking. Values ≥

0.96 have been shown to prevent pathogen

heat tolerance, but this water activity may not

be possible to achieve for all processes

(Kieboom, et al. 2006).

o Cook to a higher endpoint temperature than

the FSIS time-temperature tables, to

compensate for the low humidity conditions.

Or perform a challenge study (page 63).

Or conduct finished product testing for Salmonella

as part of on-going verification.

NOTE: Scientific gaps only affect very specific products and processes. Process deviations and malfunctioning equipment

are NOT scientific gaps. Products and Processes Not Covered by this Guideline would NOT be adequately supported by

the critical parameters listed in scientific gaps (Table 5).

Gap

Examples of

Products

1999 Critical

Operating

Parameters

Vulnerability with Continuing to Follow 1999

Parameters

5. Processes where the drying

step comes before cooking under

moist conditions.

Processes that meet this gap

include those in which products

are:

• Dried to reduce the water

activity and then cooked using

one of the following options

that ensures high relative

humidity

o Option 1, or

o Option 3, or

o Option 4, or

o Cook-in-bag, or

o Immersion cooking.

NOTE: This gap does NOT apply

products cooked after drying

without applying relative humidity

(e.g., cooking under dry conditions

or direct heat), or to dried products

cooked multiple times. It is not

supportable for dried products to

apply direct heat instead of

addressing relative humidity,

without additional support for

surface lethality (page 31).

Country-cured

hams that are

cooked-in-bag

one time.

Soups that have

a reduced water

activity due to a

high salt

concentration

but are a liquid

medium.

NOTE: Jerky

products are not

included in this

gap. There are

many validated

lethality

processes

available for

jerky products.

Apply:

FSIS time-

temperature tables

(pages 35, 37, 38),

addressing all critical

operating parameters

(page 23) and use

relative humidity:

o Option 1, or

o Option 3, or

o Option 4, or

o Cook-in-bag,

o Immersion

cooking.

NOTE: FSIS does

not consider a sealed

oven (Option 2) to be

adequate support

that the surface of

the product is

rehydrated during

cooking of reduced

water activity

products.

There is a vulnerability if pathogens develop heat

tolerance during drying which could allow them to

survive the cooking process.

To minimize this vulnerability, an establishment

may choose to implement, validate, and monitor as

part of the HACCP system, any of the following to

ensure sufficient moisture during cooking:

o Take water activity measurements of the

surface of the product before and after

cooking to support the surface is rehydrated

(water activity increases after cooking).

o Achieve the highest water activity possible

during cooking. Values ≥ 0.96 have been

shown to prevent pathogen heat tolerance,

but this water activity may not be possible to

achieve for all processes (Kieboom, et al.

2006).

Or perform a challenge study (page 63).

Or conduct finished product testing for Salmonella

and Lm as part of on-going verification.

Additional recommendations are included in

Attachment A6. Cooking Country-Cured Hams on

page 90.

NOTE: Scientific gaps only affect very specific products and processes. Process deviations and malfunctioning equipment

are NOT scientific gaps. Products and Processes Not Covered by this Guideline would NOT be adequately supported by

the critical parameters listed in scientific gaps (Table 5).

Gap

Examples of

Products

1999 Critical

Operating

Parameters

Vulnerability with Continuing to Follow 1999

Parameters

6. Products with long heating

come-up-times (CUTs).

This gap applies to processes

that require a:

• Heating come-up-time longer

than 6 hours (page 23).

NOTE: See page 62 for references

supporting longer CUTs for fully

cooked products formulated with

antimicrobials to inhibit S. aureus

that are cooked to lethality.

Ham and beef

brisket.

NOTE: Dry-

cured or

immersion cured

products

produced under

this Cooking

Guideline

Scientific Gap

may also be

produced under

a Stabilization

Guideline

Scientific Gap if

formulated

without

erythorbate or

ascorbate.

Apply any of FSIS’s

applicable time-

temperature

combinations (pages

35, 37, 38) and

relative humidity,

without considering

CUT as a critical

operating parameter.

NOTE: For intact

products,

establishment may

be able to monitor

the surface

temperature to allow

for longer CUTs,

instead of addressing

this gap (page 24).

A vulnerability exists in that S. aureus may grow

to levels that result in the production of a heat-

stable enterotoxin if CUTs are longer than 6 hours

without the use of antimicrobials.

To minimize this vulnerability, an establishment

may choose to implement, validate, and monitor as

part of the HACCP system, any of the following to

ensure S. aureus outgrowth is limited:

o Critical parameters from a

published journal

article that supports extending the come-up-

time in products and processes. (page 62).

o Reduce product diameter to reduce CUT.

o Conduct predictive pathogen modeling for a

particular product and process (page 55).

o Limit CUT between 50 – 130°F and set a

defined limit based on the shortest CUT

possible for the establishment’s specific

process.

o Apply smoke, which may inhibit S. aureus

and C. perfringens growth.

Or perform a challenge study (page 63).

Or conduct finished product verification testing for

S. aureus enterotoxins (page 77); or

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Attachment A1. Customized Processes and

Alternative Lethality Support

Following FSIS Critical Operating Parameters for Cooking (Time-Temperature Tables)

(page 23) will yield product that meets the lethality performance standards and targets.

However, some establishments may want to develop customized processing

procedures to achieve lethality. Establishments or their process authorities may

develop customized processes or an alternative lethality that meets the performance

standards or targets by using information obtained from the literature or by comparing

their processes with established processes. However, all processes must achieve a

supported Log reduction of pathogens and prevent the production of toxins or toxic

metabolites (e.g., Staphylococcus aureus) to meet HACCP requirements and produce

safe food (General Considerations for Designing HACCP Systems to Achieve Lethality

by Cooking, page 18). Regardless of the scientific support used, the establishment’s

actual process must match the critical operating parameters in the scientific support in

order to achieve adequate lethality and meet validation requirements.

In addition to the recommendations provided in the HACCP Systems Validation

Guideline, FSIS recommends that establishments and processing authorities address

the following questions when evaluating how journal articles and other sources of

alternative support may apply to a cooking process:

1. Does the scientific support (e.g., book chapters, journal articles) demonstrate that

sufficient lethality of Salmonella (or a supported surrogate) is achieved in the

product?

o Negative results obtained from finished product sampling alone (without

inoculation) are not sufficient to demonstrate that the product meets the

performance standards or targets because they do not support any

particular reduction in pathogens is achieved by the process.

o Studies should evaluate the survival of a mixture (cocktail) of Salmonella,

including strains associated with human illness and strains isolated from

meat and poultry products. Ideally, some of the strains selected should be

those with known heat-tolerance properties.

2. Does the scientific support identify all critical operating parameters used to

achieve lethality (e.g., relative humidity)?

o Many research studies designed to determine D-values of pathogens in

different food matrices use enclosed systems that maintain moisture, such

as sealed glass tubes, or impermeable bags immersed in hot water.

These studies, as published in journal articles, may not specifically list

controlling moisture during cooking as a critical operating parameter, but

the methods used inherently maintain moisture in the system. To achieve

the same result as the study, an establishment would need to consider

how its process will apply moisture to ensure lethality on the product

surface during cooking (see page 16).

Acceptability of Challenge Study Results

There are different ways to evaluate the results of challenge studies and scientific

literature, such as journal articles. The National Advisory Committee on Microbiological

Criteria for Foods (NACMCF), in its 2010 article “Parameters for Determining

Inoculated Pack/Challenge Study Protocols” recommends a statistical analysis be

performed on results or, if not, a clear justification be provided.

Below are three acceptable ways to determine if the results of the research are

sufficient to support an establishment’s lethality process:

1. The mean (average) is ≥ performance standard or target log reduction.

2. Results for all replicates are ≥ performance standard or target.

3. The lower 95% confidence limit for the results from the study is ≥ performance

standard or target.

o What this means is the reduction is calculated based on the mean log

reduction minus 1.94 times the standard deviation. The recommendation

to subtract 1.94 times the standard deviation from the mean log reduction

is based on a study with an n of 6 (i.e., three replicates and two samples

per replicate or two replicates and three samples per replicate).

The approaches are listed in order of increasing confidence the results support an

acceptable lethality process. The first approach (using the mean or average result)

provides the least confidence the lethality process will consistently achieve the

performance standard or target because it does not take into account variation found in

the results. The third approach (using the lower 95% confidence limit) provides the

greatest confidence but is also the most conservative because it takes into account a

confidence interval based on variation found during the study.

Supporting an Alternative Lethality Target (e.g., 5-Log)

Establishments that use an alternative lethality (e.g., FSIS 5-Log Table) need to

consider a number of factors that were identified in the Salmonella risk assessment,

specifically:

• Product categorization (shelf-stable or not shelf-stable).

• Pathogen load in raw materials.

• Storage and growth.

• Consumer reheating.

How is Alternative 5-Log Lethality Related to Risk of Foodborne Illness?

Historically, FSIS has recommended that establishments achieve at least a 6.5-Log

reduction of Salmonella in cooked meat products (other than beef patties which

require a 5-Log reduction). The previous recommendations were due to the Risk

Assessment of the Impact of Lethality Standards on Salmonellosis from RTE Meat

and Poultry Products, 2005 (Salmonella Risk Assessment), which showed that a 5-

Log reduction of Salmonella (instead of a 6.5-Log reduction) would result in a

greater risk of illness in cooked meat products.

The regulations for cooked beef, corned beef, and roast beef in 9 CFR 318.17(a)(1)

allow for the use of alternative lethality, provided it provides equivalent probability

that no viable Salmonella cells remain in the finished product, as well as ensures the

reduction of other pathogens and their toxins or toxic metabolites necessary to

prevent adulteration. FSIS is providing guidance to establishments regarding how to

validate the alternative lethality option of achieving at least a 5-Log reduction of

Salmonella in cooked meat products other than beef patties to ensure the lower

reduction does not result in a greater risk of illness. For shelf-stable products, that

primarily rely on means other than cooking to achieve lethality, the Salmonella Risk

Assessment did not show a substantially higher risk of illness for product with a 5-

Log reduction compared to a 6.5-Log reduction, so FSIS continues to recommend a

5-Log reduction of Salmonella for shelf-stable products. Therefore, establishments

do not need to provide additional support for decisions in the hazard analysis (9

CFR 417.5(a)(1)) if they identify a 5-Log reduction of Salmonella as the lethality

target for shelf-stable.

An establishment can use the following bulleted options to support an alternative

lethality target. The alternative lethality target may be from alternative supporting

documentation (Attachment A1. Customized Processes and Alternative Lethality

Support page 55) or with the time-temperature combinations in Table 6. Time-

Temperature Combinations for Meat Products to Achieve a 5-Log Reduction (page 59).

• Use source materials that have been tested or treated to reduce pathogens. The

establishment can use a cooking process that achieves a 5-Log lethality of

Salmonella if it uses source materials that have been tested or treated to reduce

pathogens. The establishment should maintain support (e.g., Letters of

Guarantee (LOG), Certificates of Analysis (COA), or sampling information) for

each lot demonstrating that the levels of Salmonella are low enough to be

controlled by a process achieving 5-Log reduction with an appropriate safety

margin (e.g., 2-Log). For example, an establishment may provide a LOG

indicating that a certain Log reduction (e.g., 1.5-Log or 2-Log) is achieved in the

source materials using a validated antimicrobial intervention.

• Conduct a Salmonella baseline study on the raw source material. The baseline

study should be designed such that the establishment can demonstrate, with

reasonable confidence, that less than 0.01% of the raw, formulated product

contains concentrations > 10 CFU/gram of Salmonella before cooking. This is

based on the premise that a 5-Log lethality step would reduce a Salmonella level

of < 10 CFU/gram to < 1 CFU/ 100 grams and provide a 2-Log margin of safety

(NACMCF, 2010).

Key Question

Question: Do establishments that want to use the 6.5-Log Time-Temperature Tables need to

perform raw product testing or provide other support?

Answer: No. The times and temperatures listed in the tables for 6.5-Log or 7.0-Log reductions

can be used without any additional support or testing. These time-temperature combinations

will achieve sufficient lethality as long as adequate humidity (page 26) is applied during the

process.

Challenges Supporting a 5-Log Alternative Lethality for Cooked Beef Products

FSIS recognizes that extensive baseline sampling and testing needed to apply a 5-Log lethality

may be cost prohibitive for small and very small establishments. However, this document

provides multiple options for meeting the performance standards for certain RTE products. As

noted in the question box above, establishments do not need additional testing or support to

apply the 6.5-Log Meat Table, or the 7.0-Log Poultry Time-Temperature Tables in their

process.

Table 6. Time-Temperature Combinations for Meat Products to Achieve a 5-Log

Reduction

Temperatures stated are the

minimum internal temperatures

that must be met in all parts of

the product for the total dwell

time listed

14, 15

. An establishment

must ensure both time and

temperature parameters are met

to use this table to support that

its process achieves a 5-Log

reduction of Salmonella. As

described on page 23, relative

humidity

and heating come-

up-time (CUT)

are critical

operating parameters when

using this table.

A 5-Log reduction of Salmonella is achieved instantly (0 seconds) when the internal

temperature of a cooked meat product reaches 158°F or above.

When using this table for not shelf-stable products other than meat patties, establishments

must provide additional support to show why a 5-Log reduction is sufficient to ensure pathogens

are eliminated (Supporting an Alternative Lethality Target (e.g., 5-Log) page 50).

Time-Temperatures ≥ 145°°F (in blue square) are eligible for FSIS Relative Humidity Options

1 and 2. All time-temperatures may apply to FSIS Relative Humidity Options 3 and 4 (page 26).

FSIS recommends limiting the total time product temperature is between 50 and 130°F to 6

hours or less (see page 23).

Common Topics and Journal Articles Used for Alternative Support

Many journal articles have been published that have increased scientific understanding

of the critical role of certain operating parameters during cooking including relative

humidity. FSIS recognizes that many of these journal articles, including that by Buege

et al., (2006), support the use of less than 90% relative humidity (FSIS Relative

Humidity Option 4; page 26). Establishments may use these journal articles as

scientific support as long as establishments ensure the published critical operating

parameters match the critical operating parameters being used in the establishment’s

process. FSIS agrees that wet-bulb temperature is a good indicator of surface lethality

during cooking but does not believe there is enough information at this time to make a

general recommendation that a single wet-bulb temperature can be used in place of the

FSIS relative humidity options for all products. For more information see FSIS’ wet-bulb

video available at: https://youtu.be/as-c2bCsoHQ.

Other commonly used alternatives to relative humidity include dew point temperature

and percent moisture by volume. Alternative measures are particularly valuable in

products cooked at high dry bulb temperatures. However, at this time, there is no

consensus or scientifically supported recommendation for how to use those parameters

or a targeted value to reach for each parameter. Consequently, FSIS has posted an

FSIS research priority on its website and is aware that researchers are actively

investigating this issue (Scientific Gaps Identified by FSIS page 41).

Journal articles or reports establishments may consider using as scientific support,

grouped by topic area, include:

• Validated cook schedules for making beef jerky by controlling dry bulb and wet

bulb temperatures.

o Buege, D.R., Searls, G., Ingham, S.C. 2006. Lethality of commercial

whole-muscle beef jerky manufacturing processes against Salmonella

serovars and Escherichia coli O157: H7. Journal of Food Protection.

69(9):2091-2099.

o Porto-Fett, A.C., Call, J.E., Luchansky, J.B. 2008. Validation of a

commercial process for inactivation of Escherichia coli O157: H7,

Salmonella Typhimurium, and Listeria monocytogenes on the surface of

whole muscle beef jerky. Journal of Food Protection. 71(5):918-926.

o Borowski, A. G., Ingham, S. C., Ingham, B. H. 2009. Lethality of home-

style dehydrator processes against Escherichia coli O157: H7 and

Salmonella serovars in the manufacture of ground-and-formed beef jerky

and the potential for using a pathogen surrogate in process validation.

Journal of Food Protection. 72(10): 2056-2064.

o Dierschke, S., Ingham, S.C., Ingham, B.H. 2010. Destruction of

Escherichia coli O157: H7, Salmonella, Listeria monocytogenes, and

Staphylococcus aureus achieved during manufacture of whole-muscle

beef jerky in home-style dehydrators. Journal of Food Protection.

73(11):2034-2042.

• Validated cook schedules for making turkey jerky by controlling dry bulb and wet

bulb temperatures.

o Porto-Fett, A.C.S., Call, J.E., Hwang, C.A., Juneja, V., Ingham, S.,

Ingham, B., Luchansky, J.B. 2009. Validation of commercial processes for

inactivation of Escherichia coli O157: H7, Salmonella Typhimurium, and

Listeria monocytogenes on the surface of whole-muscle turkey jerky.

Poultry Science, 88(6):1275-1281.

• Use of high temperature, short time cooking procedures and monitoring a wet

bulb temperature target. The research provides scientific support for alternative

processes including use of a wet-bulb temperature target.

o Sindelar, J.J., Glass, K., Hanson, R. 2016. Investigating the development

of thermal processing tools to improve the safety of Ready-To-Eat meat

and poultry products. Foundation for Meat and Poultry Research and

Education Final Report.

https://meatpoultryfoundation.org/research/investigating-development-

thermal-processing-tools-improve-safety-ready-eat-meat-and-poultry

Accessed 19 December 2018.

NOTE: Establishments may use this final report as scientific support until

a peer-reviewed journal article is published.

CUT Option

FSIS’s CUT option (page 23) was developed to support a wide variety of products. It is

designed to use product characteristics that would allow the most S. aureus growth

(worst-case scenario). Using worst-case conditions ensures that the option prevents S.

aureus from being a hazard in all products. Establishments may be able to identify

Why do some journal articles support using different critical operating parameters for

cooking than those recommended by FSIS?

FSIS guidance is designed to ensure lethality for a large number of meat and poultry products

across broad product categories. Research on specific processes and product types may

support adequate lethality can be achieved using different critical operating parameters for

certain products (e.g., shorter dwell time or lower endpoint temperature), but research is not

always available to support using those parameters across the many product categories and

product types that this guidance covers. Establishments may choose to follow journal articles

or other peer-reviewed scientific data instead of FSIS guidance, provided the same critical

operating parameters are met (e.g., product type, dry-bulb temperature, wet-bulb

temperature, internal product temperature, and intrinsic factors) and the process achieves

sufficient reductions for Salmonella based on the establishment’s desired target.

journal articles with longer CUT for products with specific characteristics that inhibit

pathogen growth (e.g., formulated with antimicrobials like sodium lactate).

Example:

• This following journal article provides critical limits for the brine injection and the

thermal process that control S. aureus growth and enterotoxin production during

a 14-hour CUT.

o Ingham, S.C., Losinski, J.A., Dropp, B.K., Vivio, L.L., Buege, D.R.

2004. Evaluation of Staphylococcus aureus growth potential in ham

during a slow-cooking process: use of predictions derived from the US

Department of Agriculture Pathogen Modeling Program 6.1 predictive

model and an inoculation study. Journal of food protection, 67(7):1512-

1516. https://foodsafety.wisc.edu/meat-haccp/.

• This following journal article provides critical operating parameters for hams

formulated with phosphate and cooked to lethality while applying a long CUT.

o Sindelar, J., Glass, K., Hanson, R., Sebranek, J.G., Cordray, J.,

Dickson, J.S. 2019. Validation for lethality processes for products with

slow CUT: Bacon and bone-in-ham. Food Control. 104:147-151.

NOTE: Although Sindelar et al. (2019) contains information on the growth of pathogens

during the heating CUT for partially heat-treated bacon, the article is not adequate sole

support for controlling the growth of C. perfringens and C. botulinum. Please review the

FSIS Stabilization Guideline for Meat and Poultry Products for additional details.

Predictive Microbial Modeling to Support CUT

Alternatively, establishments may use predictive microbiology modeling to develop

custom critical operating parameters. Predictive food microbiology uses models (i.e.,

mathematical equations) to describe the growth, survival, or inactivation of microbes in

food systems from knowledge of the intrinsic and extrinsic factors of the food over time.

There are many free predictive microbial models available to establishments either

online or through a download. Please refer to Predictive Microbial Modeling (page 72)

for FSIS recommendations on using predictive microbial models to evaluate S. aureus

growth during heating CUT deviations. These same recommendations can be applied

when validating a custom CUT for a HACCP system.

Designing Challenge Studies for Cooking

One of the most definitive tools at the disposal of an establishment or processing

authority for validating a process is the challenge study.

As stated in the HACCP Systems Validation Guideline, establishments may perform

challenge (or inoculated pack) studies to provide scientific support for their processes.

These studies are performed in a laboratory or pilot plant by a processing authority or

expert. The documentation on file should specify the level of pathogen reduction,

elimination, or growth control; describe the process, including all critical operating

parameters affecting the reduction or elimination of the pathogen of concern; and give

the source of the documentation. Such studies are often not published in peer-reviewed

journal articles but should contain the same level of detail as is provided for peer-

reviewed studies.

Challenge studies should be designed and conducted to accurately simulate the

commercial process. Challenge studies should be undertaken by individuals who have

a thorough knowledge of laboratory methods used in Salmonella research. Challenge

studies should be based on a sound statistical design (i.e., a statistical design that

ensures confidence in the data) and should also employ positive and negative controls.

The statistical design should include the number of samples collected at each time

interval and the number of study replicates needed to ensure the validity of the study.

There are quantitative methods for assessing the statistical quality of a study (e.g.,

power analysis). As per the National Advisory Committee on Microbiological Criteria for

Foods (NACMCF), the minimum number of samples to be analyzed initially and at each

time interval during processing or storage should be at least two. However, NACMCF

highly recommends analysis of three or more samples at each time interval. According

to NACMCF, challenge studies should include replicates. Replicates should be

independent trials using different lots of product and inoculum to account for variations

in product, process, inoculum, and other factors. When the number of samples

analyzed at each time interval is only two, NACMCF suggests it is better for the study to

be repeated (replicated) more than two times. In studies with three or more samples

tested at each time interval, two replicates are usually adequate. A cocktail of various

serotypes of Salmonella should be used in an inoculated pack study to demonstrate that

the lethality performance standard or target is met. At least five strains of the pathogen

should be used in the inoculum. Relatively heat tolerant pathogenic strains should be

included in the cocktail to develop a worst case. The serotypes/strains selected should

be among those that have been historically implicated in an appreciable number of

outbreaks.

FSIS does not require establishments to validate that their process achieves a specific

reduction of STEC or Lm in cooked product if they achieve sufficient reductions of

Salmonella because FSIS considers Salmonella an indicator of lethality for cooked

products. Without further scientific support, establishments should not use pathogens

other than Salmonella as indicators of lethality. For example, establishments should not

use reductions in Lm to support similar reductions in Salmonella without support that Lm

is at least equally as heat tolerant as Salmonella under the conditions being studied.

If an establishment chooses to conduct a challenge study in a testing laboratory, the

study should use at least five strains of Salmonella, including strains associated with

human illness and strains isolated from meat and poultry products. Ideally, some of the

Salmonella strains selected should be those with known heat-tolerance properties.

FSIS recommends that establishments and their laboratories include a justification for

the strains chosen (e.g., associated with human illness or isolated from meat or poultry

products) in the challenge study report.

In addition, the inoculum level should be at least 2-Log greater than the Log reduction to

be demonstrated. FSIS recommends that establishments use Salmonella as an

indicator of lethality (Goodfellow and Brown, 1978; Line et al., 1991) or an appropriate

surrogate of Salmonella that has similar heat and drying-tolerance properties. For

example, Enterococcus faecium has been validated as a suitable surrogate for

Salmonella during cooking of ground beef (Ma et al., 2007). FSIS considers all

Salmonella serotypes to be pathogens of public health concern. At a minimum, a study

for a microbiological food safety hazard should identify:

• The hazard (including the specific strains studied).

• The expected level of hazard reduction or prevention to be achieved.

• The processing steps that will achieve the specified reduction.

• All critical operating parameters or conditions (e.g., time, temperature, and

humidity) necessary to achieve the reduction.

• Procedures to monitor the critical operating parameters or conditions.

• The critical ingredients (e.g., concentration of salt, sugar, and cure).

• The critical product characteristics (e.g., pH, water activity, moisture level, and fat

content).

NOTE: For more information on conducting challenge studies, please review the

article, “Parameters for Determining Inoculated Pack/Challenge Study Protocols,”

Key Question

Question: Should a Challenge Study use S. Senftenberg 775W?

Answer: Not necessarily. FSIS would not require that. The FSIS Jerky Guideline states,

“One good [strain] choice, for example, might be Salmonella enterica serovar Senftenberg

strain 775W, which displays heat resistance properties (Ng et al., 1969). Salmonella enterica

serovar Senftenberg occurs in the top 10 serotypes seen in FSIS testing for both cow/bull

carcass testing and ground beef, as well as in turkeys (carcass and ground) (FSIS testing

data, 2012), so it would also be an appropriate choice for what might be seen in these

products being tested.” However, additional studies have determined that Salmonella

Senftenberg has much higher heat tolerance than other pathogens (McMinn, et al., 2018;

Veeramuthu, et al., 1998). In addition, more recent data does not continue to identify it in the

top 10 serotypes seen in FSIS testing.

published by the NACMCF in the Journal of Food Protection in 2010. For more

information on the use of positive and negative controls in challenge studies as well as

general guidance on how to select a microbiological testing laboratory please review

FSIS’ Establishment Guidance for the Selection of a Commercial or Private

Microbiological Testing Laboratory.

Attachment A2. Cooking Deviations

Corrective Actions to Perform When a Cooking Deviation Occurs

Cooking deviations occur when an establishment fails to meet its cooking CCP critical

limit for endpoint time-temperature, cooking humidity option, or heating come-up time

option. Common causes for cooking deviations include product overlap, power failures,

or breakdown of cooking equipment. Establishments are required to take corrective

actions, as required by the HACCP regulations, regardless of whether the cooking

process is addressed through a CCP or prerequisite program. This includes ensuring

no product that is injurious to health or otherwise adulterated because of the deviation

enters commerce (9 CFR 417.3(a) or (b)).

• When cooking is addressed through a CCP, establishments are required to

determine the cause of all cooking deviations, no matter how small (9 CFR

417.3(a)(1)), and ensure measures are established to prevent recurrence (9 CFR

417.3(a)(3)). If the cause of each small cooking deviation is not traced and

corrected when first noticed, the problem will likely recur and become more

frequent and more severe. The establishment should consider an occasional

small process deviation to be an opportunity to find and correct a process control

problem. Large process deviations or continual small ones always constitute

unacceptable risk. Also, continual or repetitive process deviations from the

critical limit demonstrate that the establishment is unable to control its process

and that its corrective actions are not preventing recurrence as intended.

• When cooking is addressed through a prerequisite program and a deviation

occurs, establishments are required to reassess their HACCP system to

determine whether the newly identified deviation or unforeseen hazard should be

addressed and incorporated into the HACCP plan (9 CFR 417.3(b)(4)). Also, an

establishment may not be able to continue to support the decision in its hazard

analysis that pathogens are not reasonably likely to occur, if it has continual or

repetitive deviations from its cooking prerequisite program (9 CFR 417.5(a)(1)).

To assist establishments in determining and supporting product disposition as required

9 CFR 417.3(a) or (b), FSIS is including information regarding potential pathogens of

concern during different types of cooking deviations and recommendations for using

pathogen modeling and sampling. Establishments should carefully evaluate each

deviation as each situation is unique and needs to be evaluated individually. Ultimately,

the establishment should rely on the expertise of a processing authority to determine

the severity of cooking deviations and subsequent appropriate disposition of the product

in question. Knowledge of the specific product and factors that would favor or inhibit the

growth of various bacterial pathogens is essential to determine product safety. As

stated in the HACCP Systems Validation Guideline, the advice of processing authorities

should include reference to established scientific principles as well as reference to peer-

reviewed scientific data.

Pathogens of Concern During Cooking Deviations

Cooking deviations can allow pathogens that are controlled under normal cooking

procedures to become a hazard, depending on the type of cooking deviation (described

below) that occurs. Specific pathogens of concern may include:

• Salmonella, STEC (in beef products), and Lm, which could grow as vegetative

cells to levels that overwhelm the Log reductions achieved by cooking.

• S. aureus, if allowed to grow to high levels, may produce heat-stable enterotoxins

in the food.

• Bacillus cereus (B. cereus) (in rare cases), if allowed to grow to high levels in the

food, may produce a heat-stable emetic toxin in the food or enterotoxins in the

small intestine.

• Clostridium perfringens (C. perfringens) and Clostridium botulinum (C. botulinum)

spore-forming pathogens that can germinate and grow in product held at higher

temperatures (e.g., > 80°F).

Again, it is important someone knowledgeable such as a processing authority evaluates

each deviation to determine the pathogens of concern.

Three Common Types of Cooking Deviations

When cooking products to lethality, deviations may occur due to three main reasons:

1. The establishment fails to meet a time--temperature parameter in its lethality

CCP for meat or poultry products.

2. The establishment fails to maintain sufficient humidity during the cooking step.

3. Slow heating CUT allows product to remain at temperatures that allow pathogen

growth (e.g., product remains at temperatures 50°F to 130°F for more than 6

hours; see FSIS Critical Operating Parameters for Cooking Come-Up-Time

(CUT), page 23).

Specific recommendations for evaluating each type of cooking deviation, including the

pathogens of concern, are provided below. Alternatively, the establishment can provide

additional support for the safety of the product (e.g., a journal article, or support from a

processing authority). These are general recommendations; the specific responses will

vary based on the unique factors of each deviation.

Type 1. Missed Endpoint Time-Temperature

When evaluating product disposition after the process fails to meet an endpoint time or

temperature parameter, the first step is to assess whether the process met a different

time-temperature combination in the reference table. In some cases, the process may

not have achieved an instantaneous lethality temperature (e.g., 158°F for meat)

identified in the CCP but may have achieved the dwell time needed for a lower

temperature in the same table (e.g., 154°F for 27 seconds) when considering the total

time product temperature was at or above the lower temperature.

Did the process meet a different validated time-temperature combination?

• If yes, then product is safe to release.

• If no, then FSIS recommends contacting a processing authority who may help

you identify proper D and z values to calculate integrated process lethality

considering the product come-up -time and come-down-time. One common tool

for calculating integrated lethality is the AMI Process Lethality Determination

Spreadsheet. If properly conducted, the AMI lethality spreadsheet is a sound

scientific approach for determining the overall lethality of a cooking process

(Scott and Wedding, 1998). The D-values at the reference temperature for the

three main pathogens of concern (Salmonella spp. E. coli O157:H7, and Lm) are

generally conservative values and should be valid for most cooked meat ready-

to-eat (RTE) processes provided that the product is moist when cooked (high

relative humidity). However, if the product is not moist when cooked and the

product surface is allowed to dry out during the lethality step, the D-values

referenced in the AMI lethality spreadsheet are not valid.

NOTE: There are many complexities involved in identifying appropriate D and z

values needed as inputs for calculating integrated pathogen lethality. FSIS

advises establishments to work with a processing authority or someone

knowledgeable in thermal death-time values, to ensure they select appropriate

values and are properly using the lethality calculator.

• Establishments may consider recooking the product, but only if all critical

operating parameters (including relative humidity and CUT time) were met during

the initial heating and during recook.

o If the relative humidity option in the scientific support was not applied,

the establishment should also follow recommendations for evaluating a

Type 2 Deviation: Insufficient Humidity During Cooking described on

page 69, or

o If the CUT parameter was not met, the establishment should also

follow recommendations for evaluating a Type 3 Deviation: Long

Heating CUT described on page 70, and contact a processing

authority for assistance.

NOTE: Cooking deviations that combine a missed time-temperature

parameter with a long CUT are complex situations which may require

considering C. perfringens and C. botulinum as described in the

Stabilization Guideline, in addition to the other pathogens of concern.

• If establishments cannot recook the product, they should consider the following

alternative actions:

o Provide alternative support (page 55) (e.g., information from a

processing authority that includes scientific citations that product is

safe to release);

o Sample and test the product (see Product Testing recommendations

for Type 1 deviations, page 77); or

o Destroy the product (renderer or landfill).

Type 2. Insufficient Humidity During Cooking

As described on page 16, some bacteria can become more heat tolerant when they are

exposed to moderate levels of heat, drying, and other factors. Bacteria can then survive

at higher temperatures than they normally would. Below are general recommendations

for an establishment to consider when evaluating products after a Type 2 cooking

deviation resulting from insufficient humidity (i.e., the relative humidity option in the

scientific support was not followed) during cooking.

• Consider sampling and testing product for Salmonella, Lm, and E. coli

O157:H7 (if a beef product), using a statistically based sampling program as

described in Product Testing on page 77.

• If recooking, apply a higher time-temperature combination validated to achieve

lethality in a product with similar intrinsic factors (e.g., water activity).

o It would not be appropriate to recook the product following FSIS

Relative Humidity Options (page 26) without additional support that

recooking conditions adequately rehydrate the product surface (see

Attachment A6. Cooking Country-Cured Hams, page 90).

o Under these circumstances, FSIS would need to verify that such

scientific support is adequate in the context of the specific product,

process, and situation. Examples of acceptable support may include

support that:

 Demonstrates that a validated wet bulb temperature target has

been met to ensure lethality. To show that the surface has been

rehydrated, the wet bulb target should be higher than the product

surface temperature.

 Includes water activity testing: A water activity increase after

recooking (compared to water activity before recooking), may

indicate that the surface has been rehydrated.

NOTE: FSIS is not aware of any research validating recooking procedures for

products that may have heat tolerant Salmonella because of a lack of relative

humidity during the initial cook. However, FSIS plans to update these

recommendations as more research becomes available.

Type 3. Long Heating CUT

If the total time between 50 and 130°F is longer than hours 6, recooking alone may not

be sufficient to ensure the safety of the product. That is because during the extended

CUT toxigenic pathogens could grow rapidly (e.g., S. aureus), allowing enterotoxins to

form. Some enterotoxins are extremely heat-stable and are not inactivated by normal

cooking temperatures. Therefore, it is not always possible to recook the product alone

to ensure its safety. The establishment should continue to recook the product to

address vegetative pathogens (e.g., STEC, Lm, and Salmonella). It should also provide

additional support that heat-stable enterotoxins do not present a hazard in the product

after the recooking step.

As noted in Type 1. Missed Endpoint Time-Temperature, cooking deviations that

combine a missed time-temperature parameter with a long CUT are complex situations

that may require considering C. perfringens and C. botulinum as described in the

Stabilization Guideline, in addition to the other pathogens of concern. The

establishment may want to contact a processing authority for assistance.

To determine product disposition after a long heating CUT deviation, the establishment

should:

1. Address growth of vegetative pathogens that do not produce toxins, AND

2. Address the potential enterotoxin formation as described below.

If either hazard is not controlled to safe levels, then product should be destroyed.

Further guidance on these two recommendations is provided below:

1. Address growth of vegetative pathogens: (e.g., STEC, Lm, and Salmonella).

o FSIS recommends that establishments use microbial modeling (page

72) and other information (e.g., scientific journal articles, book

chapters, and processing authorities) to estimate growth of E. coli, Lm,

and Salmonella.

 If modeling estimates the growth of vegetative pathogens to be 1-

Log or less, provided the predictive microbial modeling program is

validated, modeling is adequate to show that the process prevented

vegetative pathogen outgrowth and the establishment can address

the potential for enterotoxin formation (see 2 on the next page).

 If modeling estimates more than 1-Log growth of any vegetative

pathogen, establishments should recook product OR sample and

test for vegetative pathogens to determine the safety of the product

(see Type 3 deviation recommendations in Product Testing, page

77).

• Many establishments avoid the cost of sampling and testing

by recooking the product or consulting a processing authority

to identify alternative support that vegetative pathogens are

addressed.

• If product is recooked, it should be done to a higher time

and temperature that has been shown to achieve enough

additional Log reductions to address the amount of

vegetative cell growth the model predicted. Using a recook

procedure that achieves the correct additional Log reduction

is important to ensure increased pathogen load will not

overwhelm the Log reductions achieved during the recook

procedure (see page 72). For example, if predictive

microbial modeling showed a 2.5-Log and 3.0-Log increase

for Salmonella and E. coli O157:H7, respectively, in a roast

beef product, the recook step should be adjusted so that the

cooking time-temperature combination can achieve at least a

9.5-Log reduction of Salmonella instead of a 6.5-Log

reduction. The AMI Process Lethality Determination

Spreadsheet discussed on page 68 may be used to support

the cooking time-temperature combination can achieve

sufficient Log reductions.

2. Address potential enterotoxin formation: (e.g., S. aureus) by demonstrating

that toxigenic pathogens did not grow to levels of public health concern or

produce enterotoxin.

o FSIS recommends that establishments use microbial modeling (page

72) and other information (e.g., scientific journal articles, book chapters,

and processing authorities) to provide additional information to

determine product safety.

 If predictive microbial modeling estimates a < 3-Log growth of S.

aureus, modeling is adequate to show that the process prevented

enterotoxin formation provided the predictive microbial modeling

program is validated. If growth of vegetative pathogens is also

addressed the product can be released.

NOTE: Due to the rapid growth of S. aureus in meat and poultry

products, modeling for B. cereus (which grows slower) is not

needed when S. aureus growth is controlled (< 3-Log).

 If microbial modeling estimates a ≥ 3-Log growth of S. aureus,

then product should be tested for S. aureus enterotoxins A, B, C,

D, and E using a statistically representative sampling procedure. If

the product contains non-meat ingredients previously associated

with B. cereus associated illnesses (e.g., rice, or pasta) and

microbial modeling estimates > 3-Log growth of S. aureus, then

establishments may also want to consider testing for B. cereus

emetic toxin (Product Testing page 77).

NOTE: As stated previously, conditions that allow for 3-Log or

higher growth of S. aureus are a public health concern (ICMSF,

1996). Furthermore, this level of growth (i.e., 3-Log) for S. aureus

is consistent with the pass/fail criteria developed by the Institute of

Food Technologists (IFT) for the FDA to control for this food safety

hazard (IFT, 2003).

To support safe release of the product, both the vegetative pathogens and

enterotoxin formation must be addressed with supporting documentation. If

either hazard is not controlled to safe levels, then product should be destroyed.

Predictive Microbial Modeling

Establishments may use predictive microbial modeling to estimate the relative growth of

bacteria during a long heating CUT deviation (Type 3). As explained above for Type 3

heating deviations, modeling results can be used to support various product disposition

options including release, recooking, sampling and testing, or destruction provided the

model used has been validated. Predictive microbial modeling tools may be used to

evaluate product disposition in the event of other types of deviations (e.g., for Type 1

deviations establishments may use the AMI Process Lethality Determination

Spreadsheet). However, this section is focused on evaluating product disposition

during Type 3 heating deviations due to their complexity.

When performing predictive microbial modeling, it is important that establishments:

1. Use validated models (see examples below):

o It is not appropriate to rely solely on one model unless the model has been

validated for the particular food of interest. A validated cooking model is a

model whose predictions have been found to agree with or are more

conservative than actual observed results. If a model has not been

validated for a particular food of interest, the establishment should provide

additional supporting documentation to support the results from the model

(e.g., sampling data or comparison with other model results).

2. Enter accurate product formulation information:

o FSIS recommends entering the raw product formulation values for Type 3

Deviations: Long CUT, since the high moisture values at the start of

cooking will support faster pathogen growth and therefore represents the

worst-case scenario. If using finished product values, establishments

should provide reasoning for how that represents the product matrix

during CUT.

3. Enter accurate time and temperature information in the model:

o When entering time and temperatures into the model, the establishment

should include all parts of the process, including cooking and recooking

CUTs after a Type 1 or 3 cooking deviation. If the establishment does not

include all parts of the process, it may underestimate pathogen growth.

o When determining the temperature, the establishment should take into

account both the temperature at the coldest internal area (center) of the

product and at the surface of the product.

o It is important to obtain an internal time and temperature profile of the

product, and a wet bulb time and temperature profile of product since wet

bulb can be used to describe the product’s surface temperature. If an

establishment does not have wet bulb temperature data, it can conduct

predictive microbial modeling using the internal time-temperature profile of

the product, provided that sufficient humidity was used during cooking.

However, the establishment should take into account that the product

surface temperature will be higher than the center of the product under

high relative humidity conditions.

o For cases with large time gaps between known temperature observations,

establishments may consider interpolating to estimate additional time-

temperature data points between known observations assuming linear

heating. However, if the product temperature dwells or holds between 90

and 120°F (the optimal growth range of S. aureus) for an extended period

of time, excess S. aureus growth could result in a potential hazard in the

product being uncontrolled. The establishment should consider the likely

accuracy of the predicted growth when making a product disposition

determination using linear interpolation.

o Assume no S. aureus growth above 120°F.

NOTE: FSIS has included the time that product remains from 120 to

130°F in the heating CUT option (page 23) to reduce the risk B. cereus (a

spore-former) could germinate and then grow at these higher

temperatures, potentially producing a heat-stable emetic toxin.

4. Address model limitations in a conservative manner:

If product characteristics or other conditions are outside the range of the

model, accuracy is not guaranteed. Establishments should support how

the model results represent the product or the worst-case scenario for the

hazard in the product or should compare the results to several other

pathogen models and should make decisions based off the model that

shows the worst-case scenario (i.e., for S. aureus that is the model that

estimates the most outgrowth).

NOTE: This guidance contains recommendations for addressing certain limitations

in two recommended models at the time the guidance was written. Neither modeling

program is controlled by USDA-FSIS and may change. FSIS will update its

modeling recommendations in future revisions to be consistent with any changes

made to the modeling programs.

Recommended Models

• Therm 2.0 model (S. aureus, Salmonella, and E. coli O157:H7).

The University of Wisconsin Therm 2.0 model is designed to allow processors to

input the product’s time-temperature profile and it has been validated for

estimating the growth of S. aureus, Salmonella, and E. coli O157:H7.

The three input variables and their ranges for entering into the growth model are

provided below (Ingham et al., 2009):

o Input variables and ranges:

 Temperature profile: 50°F to 110°F (10ºC to 43.33ºC)

 Date/time: the model allows for entry of calendar date and time

 Meats:

• In meat and poultry products containing salt (≤ 2.5%),

establishments should use the Therm 2.0 model for

Bratwurst for predicting pathogen growth. This model

should be used because it was designed to take into account

the bacterial pathogen’s behavior in pork sausage and

related products that contain higher fat levels, sodium

chloride, and spices. For example, adding salt to product

will inhibit the competing microorganisms, but allow for

greater growth of salt tolerant S. aureus; the Therm 2.0

model will predict this. Because the Therm 2.0 model for

Bratwurst was developed with data from a pork product,

establishments should compare the results with another

model, such as the DMRI Staphtox Predictor when

evaluating deviations involving poultry products.

• In meat and poultry products without any added salt,

establishments should use the Therm 2.0 model for Beef,

Pork, or Poultry based on the product type (Ingham et al.,

2009).

o Overcoming model temperature limitations: (maximum 110°F)

 The Therm 2.0 model does not automatically interpolate

(estimate a linear change) between time-temperature data points

entered by the user. Therefore, FSIS recommends establishments

enter temperature observations for at least every 30 minutes, or at

the lowest time interval available.

 For temperatures >110°F, substitute 110°F for any temperature

above 110°F up to 120°F. S. aureus grows fastest at 110°F. The

growth rate slows as temperatures increase from 110 to 120°F.

Modeling using 110°F for temperatures observed from 110 to 120°F

will slightly overestimate the growth of S. aureus.

 For temperatures between 120 and 130°F assume no growth of S.

aureus (leave this out of the model).

• DMRI Staphtox Predictor (Version 1.0) (S. aureus)

The Danish Meat Research Institute’s (DMRI) Staphtox predictor (Version 1.0)

may also be used to predict the growth of S. aureus in meat and poultry

products, with added salt (i.e., 1.8% to 4.2%). This model has been validated

and was specifically designed to predict the growth of S. aureus in different meat

product processes based on product composition and changes in temperature.

The six input variables and their ranges for entering product composition

information into the growth model are provided below (Gunvig et al., 2018):

o Input variables and ranges:

 Temperature profile: 32°F to 105.6°F (0ºC to 40.9ºC)

 pH: 4.4 – 6.1

 % sodium chloride (NaCl) in product (based on the total weight of

the product formulation): 1.8 – 4.2%.

NOTE: The model converts % sodium chloride (NaCl) into the %

water-phase salt.

 % potassium chloride (KCl) in product (based on the total weight of

the product formulation): 0.0 – 4.2%

 Sodium nitrite added to product: 0 – 150 ppm

 % water in final product (as determined through laboratory

analysis): 62 – 78%

o Worst Case Scenario: FSIS recommends using the values listed below

as model inputs for any products where the values are unknown. These

values represent a worst-case scenario for the growth of S. aureus based

on product composition:

 pH: 6.1

 % NaCl in product: 1.8%

 % KCl in product: 0.0

 Sodium nitrite added to product: 0 ppm

 % water in final product: 78% (highest allowed in model)

 Initial level S. aureus: 100 CFU/g

o Overcoming model temperature limitations: (maximum 105.6°F)

 For temperatures > 105.6°F (40.9°C), substitute 105.6°F for any

temperature above 105.6°F (40.9°C), up to 120°F (48.9°C). The

fastest growth in this model is at 105.6°F. As described above, S.

aureus continues growing at higher temperatures, but the growth

rate slows as temperature increases up to 120°F (48.9°C). For

modeling, use 105.6°F for temperatures observed from 105.8°F

(41°C) up to 120°F (48.9°C), which will slightly overestimate the

growth of S. aureus (fail-safe).

 For temperatures between 120°F (48.9°C) and 130°F (54.4°C)

assume no growth of S. aureus (leave out of the model).

NOTE: Establishments may use the ComBase S. aureus model as support. However,

this model has not been validated and establishments should follow the

recommendation for using models that are not validated (i.e., compare the results of

several models and make decisions using the worst-case results) as described above.

Product Testing

As described in the cooking deviation and the microbial modeling recommendations

(pages 67-72), if the establishment is unable to support the product disposition through

predictive microbial modeling or some other means, the establishment can test a

statistically-based number of samples of the product to support its safety. Table 7

identifies the hazards to be tested for according to the type of cooking deviation that

took place. These are general recommendations; it is important that someone

knowledgeable such as a processing authority evaluate each deviation to determine the

appropriate sampling and testing plan.

Table 7. FSIS Recommendations for Product Sampling and Testing After Each

Type of Cooking Deviation to Determine Product Disposition

Type of Heating

Deviation*

Vegetative Pathogens

Heat-stable

Enterotoxins

Salmonella

E. coli

O157:H7

S. aureus

Enterotoxins

A, B, C, D, and E

1 - Missed Time-Temperature

X X

2 - Insufficient Humidity

X X X

3 - Long CUT

Multiple Types in Combination

(i.e., missed time-temperature

AND long CUT)

Contact a processing authority for assistance evaluating

product disposition in a complex deviation which combined

multiple types of heating deviation. May need to consider C.

perfringens and C. botulinum in addition to the hazards listed

in this table

*Cooking deviation Types 1-3 are described on page 66.

**E. coli O157:H7 testing recommended only for products containing beef. Establishments may also

choose to test for other STEC; however, testing for E. coli O157:H7 alone is sufficient.

Sampling in Response to a Cooking Deviation

• The establishment should test a statistically representative number of samples

per lot depending on the bacterial pathogen. FSIS recommends testing at least

10-15 products per lot as outlined by the two-class sampling plan (Case 11 and

Case 13, respectively) per the International Commission on Microbiological

Specifications for Foods (ICMSF, 2002).

• If the product contains non-meat ingredients previously associated with B. cereus

associated illnesses (e.g., rice, or pasta) and microbial modeling estimates >3-

Log growth of S. aureus, then establishments may also want to consider testing

for B. cereus emetic toxin.

NOTE: FSIS does not recommend all products to be tested for B. cereus emetic

toxin due to the low incidence of B. cereus in raw meat and poultry. If you are

uncertain if the formulation of product affected by a cooking deviation may need

to address B. cereus emetic toxin as a potential hazard, please contact askFSIS

(page 9).

Key Question

Question: Can samples be composited for lab testing?

Answer: It depends on what the sample is being tested for:

• Enterotoxins? No. FSIS does not recommend compositing samples to be

tested for enterotoxins. Combining multiple samples for a single test (i.e.,

compositing) could prevent the test from detecting enterotoxins in the product.

• Vegetative pathogens? Yes. However, the number of samples that can be

combined depends on the pathogen. Additionally, establishments should

ensure the lab method has been validated for the larger test portion.

o Salmonella and E. coli O157:H7: FSIS recommends compositing up to

3 samples (total 75g) for a total of 5 analyses although establishments

may also be able to support compositing up to 15 – 25-g samples (total

375 grams). The establishment would collect 15 samples from different

pieces of product. The lab would combine the 25g sample from each of

3 different pieces, to make a 75g composited sample for analysis. The

lab analyzes 5 composited samples. When compositing,

establishments should ensure the method has been validated for the

larger test portion. FSIS has validated a 325g test portion size for its

analysis of RTE product samples collected under the RTEPROD

program (see the FSIS’ Microbiology Laboratory Guideline Salmonella

Chapter).

o Lm: FSIS recommends compositing up to 5 samples (total 125g) and 3

lab tests total. The establishment would collect 15 samples from

different pieces of product. The lab would combine the 25g test sample

from each of 5 different pieces, to make a 125g composited sample for

analysis. The lab analyzes 3 composited samples. When compositing,

establishments should ensure the method has been validated for the

larger test portion. FSIS has validated a 25g and 125g test portion size

for its analysis of RTE product samples collected under the RTEPROD

and RLm programs, respectively (see the FSIS’ Microbiology

Laboratory Guideline Listeria monocytogenes Chapter).

Disposition after Testing Results:

To support the safe release of the product, every hazard associated with the type of

heating deviation identified (see Table 7) must be controlled for the safe release of

product. If any single hazard is not controlled, then product should be destroyed

(renderer or landfill).

• Enterotoxins:

o If the product tests negative for enterotoxins, product can be released,

unless insanitary (or other) conditions exist that could adulterate the

product (e.g., vegetative pathogens).

o If any enterotoxin is found, the lot is adulterated, and product should be

destroyed (renderer or landfill).)

• Vegetative Pathogens:

o If the product tests negative for vegetative pathogens, product can be

released, unless insanitary (or other) conditions exist that could adulterate

the product (e.g., enterotoxins).

NOTE: It would be inappropriate to test for live S. aureus instead of

enterotoxin because it is possible for S. aureus to produce

enterotoxins prior to the death of the bacteria (e.g., during cooking).

The food product would still cause illness even though no vegetative

bacteria were found.

o If any vegetative pathogens are found, the lot is adulterated. Product may

be:

 Recooked per Type 1 or Type 2 recommendations (pages 67-69);

 Destroyed (rendered or denatured per 9 CFR 314.3(a), 9 CFR

325.11(a), 9 CFR 325.13(a)(1) through 325.13(a)(7), or 9 CFR

381.95 and sent to a landfill).

Common Mistakes made by Establishments when Evaluating

Heating Deviations—and the Recommended Solutions

1) The establishment did not input an accurate internal time-temperature profile into

the model. The establishment should be using a data logger or collecting time

and temperature data at regular intervals during cooking. The establishment

should take into account all parts of the process and temperatures at both the

center and surface of the product (Monitoring Endpoint Temperature page 21 and

Monitoring Surface Temperature page 24).

2) In Type 1 or 3 deviations with a missed time-temperature parameter, the

establishment failed to take into consideration the amount of bacterial growth that

could occur during the cooking come-up-time when the cooking cycle was

restarted. To address this issue, the establishment should consider both the

original come-up-time, the initial cooling, and second come-up-time when the

cooking is restarted as part of its modeling.

3) The establishment did not address whether additional growth of Salmonella, E.

coli O157:H7 and Lm could have occurred during the Type 1 heating deviation

and whether heat tolerance could have developed. To address this issue, when

recooking the product, the establishment should increase endpoint time-

temperature and apply sufficient humidity (FSIS Relative Humidity Options page

26).

4) The establishment failed to address the amount of growth of S. aureus and other

bacterial pathogens that could occur on the product’s surface. Measuring the

temperature both at the product center and at the surface (wet bulb) temperature

would address this issue.

5) The establishment failed to take into account the initial levels of S. aureus

commonly found in raw meat and poultry. Levels of pathogens in raw product are

approximately 2-Log. Increases of 3-Log or more could result in conditions where

enterotoxin could be formed. Establishments should limit S. aureus growth to 2-

Log or less, to support safe release of product based on microbial modeling. See

Biological Hazards of Concern During Cooking subsection: Staphylococcus

aureus (page 14) for more information.

Attachment A3. When can Products be Labeled as

Pasteurized?

FSIS defines pasteurization as any process, treatment, or combination thereof, that

eliminates or reduces the number of pathogenic microorganisms to achieve at least a 5-

Log reduction of either Salmonella or Lm, on or in ready-to-eat (RTE) meat or poultry

products in the final finished package.

With adequate validation, pasteurization processes may include alternative

technologies other than traditional cooking (e.g., high pressure processing (HPP)).

FSIS considers products with a raw appearance that have been treated with a lethality

process that renders the product RTE, and that are not post-lethality exposed (e.g.,

“steak tartare” subjected to a HPP treatment) as pasteurized.

For the product to be labeled “pasteurized,”

the treatment needs to:

1) Be applied in the final package (product

is not post-lethality exposed);

2) Be sufficient to eliminate the number of

pathogenic microorganisms to make the product safe for human consumption (so

there are no detectable pathogens; RTE), and

3) Be effective for at least as long as the product shelf life.

Establishments may label products as “pasteurized.” However, the term “pasteurized”

is a special statement and claim that needs to be submitted to the Agency for label

approval under 9 CFR 412.1(c)(3). The request for label approval needs to include

supporting documentation providing evidence that the process achieves a 5-Log

reduction of Salmonella or Lm. For more information see the FSIS Compliance

Guidance for Label Approval.

Irradiation is not a pasteurization process.

Although the effect is similar to

pasteurization, FSIS considers ionizing

radiation a food additive under 9 CFR 424.22.

Attachment A4. Sources of

Salmonella

Contamination in RTE Products and Best Practices

to Address It

Although the Salmonella percent positive found in ready-to-eat (RTE) products is low,

the presence of Salmonella in RTE products may indicate a serious processing and

public health problem. Common sources of Salmonella in RTE products include:

• Under processing.

• Cross-contamination.

o Product contact surfaces that are contaminated with Salmonella; or,

o Raw product contact with RTE product.

• Ingredients added to the product or the sauce after the cooking step.

• Improper handling by establishment employees.

• Insect or animal vectors.

Each common source of Salmonella contamination on RTE products and best practices

to prevent the hazard are discussed in detail below.

Under-Processing

Under-processing occurs when the lethality treatment is not adequate to eliminate the

pathogens of concern. For heat-treated product, under-processing may result from

inadequate cooking or the development of bacterial heat tolerance due to drying of the

product’s surface before completion of the lethality step because of inadequate humidity

(see FSIS Critical Operating Parameters for Cooking (Time-Temperature Tables) page

23).

Cross-Contamination

Cross-contamination of product can occur from situations such as the following:

• Using the same equipment (e.g., slicers) for both raw and cooked products

without complete cleaning and sanitizing of the equipment (as should be

addressed in the establishment’s Sanitation Standard Operating Procedure

(SOP)) after raw production and prior to RTE production.

o In a for-cause Food Safety Assessment (FSA) in response to a

Salmonella positive in a RTE head cheese product, FSIS identified

equipment used to grind both raw and cooked ingredients for head cheese

was not cleaned and sanitized between use for raw and cooked meat

potentially resulting in Salmonella cross-contamination.

• Placing cooked product on the same surface (e.g., cutting table) as raw product

without complete cleaning and sanitizing of the surface before reuse.

• Using the same utensils or containers (e.g., scoops or buckets) for both raw and

cooked product.

o In two FSAs, popped pork skins were most likely contaminated with

Salmonella when the same buckets and tongs were used for handling

both raw and RTE product.

• Condensation or aerosolization in the processing environment.

Best Practices to Prevent Cross-Contamination

Under the HACCP regulations, establishments are required to prevent contamination of

product with pathogens after the lethality step. Establishments are required to maintain

sanitation in the RTE area to ensure that food contact surfaces are free of

contamination from pathogens such as Lm and Salmonella. Best practices include:

• Completely separating the processing areas by time or space (e.g., scheduling

raw and RTE processing on different days).

• Installing separate air ventilation systems that are designed to prevent or

minimize condensation and other potential air contaminants. If separate

ventilation systems are not feasible, ensure that airflow is directed from the RTE

areas to the raw areas.

• Using separate equipment for RTE and raw processing. If this is not possible,

schedule use of equipment first for RTE processing and then for raw processing.

• Restricting travel of personnel from the non-RTE area to the RTE area during

processing.

• Establishing proper sanitation procedures for equipment that is moved from a

non-processing area to an RTE processing area to prevent product

contamination from the equipment during operation.

• Avoiding passing raw product through RTE areas and passing RTE product

through raw production areas.

• Not allowing RTE product in coolers to come into contact with raw products or

surfaces that may be contaminated.

• Discarding products that touch environmental surfaces (e.g., product that has

fallen on the floor) if the product cannot be properly reconditioned to ensure that

any possible contamination is eliminated.

• During cleaning and sanitizing, following proper sanitation procedures to ensure

that no food residue is left on the equipment.

• When adding ingredients to a second container, avoiding any contact between

the ingredient container and the interior of the second container.

Ingredients Added After the Lethality Treatment

Salmonella contamination may occur from the addition of uncooked vegetables (e.g.,

tomatoes and onions), fresh herbs, eggs, spices (that may or may not have been

treated to eliminate Salmonella), or other ingredients (e.g., nuts, hydrolyzed vegetable

protein (HVP)) to processed meat and poultry products after the primary lethality

treatment. Sauce that has not undergone a lethality treatment may also be a source of

contamination of the finished product, even if the pH is low. The safety of all ingredients

added to the product after the lethality step should be considered, even if they are

normally considered RTE. In some cases, FSAs determined the addition of seasonings

or other ingredients after the cooking step resulted in the contamination of RTE product

with Salmonella. Failure to identify all steps in a process, including the addition of

contaminated ingredients and sauces, can result in an inadequate food safety system.

Outbreaks related to ingredients added after lethality treatment

An outbreak and several recalls of meat and poultry products that were prepared using

Salmonella-contaminated ingredients exemplify the need to ensure the safety of all

ingredients added to the product after the lethality treatment. Examples include a 2010

outbreak-related recall of salami products coated with contaminated pepper (RC-006-

2010) and recalls involving products containing HVP that was the subject of an FDA

recall (i.e., bacon base, RC-015-2010; beef tornados, RC-016-2010, and beef taquitos

and chicken quesadillas, RC-017-2010). RC-055-2010 may have been due to

contaminated sauce added to the product after the lethality step. There have also

been two recalls of meat and poultry salads containing Salmonella contaminated

tomatoes recalled by the supplier (RC-033-2011 and RC-79-2011), and Caesar salad

containing contaminated cilantro that was the subject of an FDA recall (RC-059-2012).

In 2018, there were 12 recalls due to potential vegetable contamination with

Salmonella and Lm that were triggered by an FDA investigation and subsequent recall

from the same supplier (RC-092-2018, RC-093-2018, RC-094-2018, RC-095-2018,

RC-096-2018, RC-097-2018, RC-098-2018, RC-099-2018, RC-100-2018, RC-101-

2018, RC-102-2018, and RC-103-2018).

Requirements and Best Practices to Prevent Hazards from Ingredients Added

Post-Lethality

Establishments are required to:

• Ensure all ingredients and other articles used in the preparation of any meat or

poultry product are clean, sound, healthful, wholesome and otherwise such as

will not result in the product being adulterated (9 CFR 318.6 and 9 CFR

424.21).

• Consider any potential food safety hazards at the step in the process where the

non-meat ingredient is ‘received’ into the food safety system (9 CFR 417.2(a)(1))

and document any controls it needs to support its decisions (9 CFR 417.5(a)(1))

about those hazards.

o Establishments may choose to use COAs that include negative test results

for each lot of the non-meat ingredient as support or may test each lot of

non-meat ingredients upon receipt; however, establishments have

flexibility and do not have to only rely on testing.

o Alternatively, establishments may maintain supporting documentation

demonstrating that the ingredients such as spices, have been treated by

processes to kill pathogens (e.g., irradiation, ethylene dioxide, steam

treatment of spices), or they can apply a lethality treatment to the

ingredients (e.g., cook the sauce of a pork BBQ).

o In most cases, a LOG alone would not be sufficient to support the safety

of non-meat ingredients added to a product unless they indicate how each

lot of ingredients is processed, tested, treated, or otherwise processed to

ensure its safety as described in the bullet above.

o A LOG can be used to support the safety of pre-packaged ingredients

(e.g., ketchup or mustard) that have not been associated with previous

outbreaks or recalls.

NOTE: Many frozen vegetables are considered NRTE by the producing facility. FSIS

recommends establishments that do not receive a COA or LOG as described in the

bullets above, treat all frozen vegetables as NRTE and address potential hazards from

this ingredient (e.g., by testing each lot of non-meat ingredients upon receipt or applying

a validated lethality treatment). Additionally, any vegetables labeled with cooking

instructions are to be treated as NRTE.

• Developing procedures to ensure that spices or other source materials are

maintained under sanitary conditions and are not contaminated by the

introduction of pathogens during repeated opening of the container and removal

of the ingredient for use in multiple production lots.

• Taking steps to ensure sauce used for RTE products is also not contaminated by

exposure to unclean surfaces, untreated ingredients, or contact with raw

products.

Food Handlers

There is a high incidence of salmonellosis in the US. Additionally, some people can be

asymptomatic carriers that spread Salmonella without appearing ill. Establishment

employees that are asymptomatic carriers may be a source of Salmonella in RTE

products.

Best Practices to Prevent Hazards from Food Handlers

Food handlers, employees, and supervisors at food preparation facilities should:

• Stay home from work when having symptoms of vomiting or diarrhea and wait to

resume work until at least 24 hours have passed since the vomiting and diarrhea

symptoms ended.

• Wash hands upon resuming duties after breaks and before putting on gloves.

• Wear separate or color-coded frocks in RTE areas of the establishment and

control employee traffic between raw and RTE production areas.

• Train employees in proper hygiene practices, and regularly monitor those

practices, and retrain employees at least annually.

• Develop and maintain procedures to ensure that sanitizer concentrations in

footbaths are monitored and maintained adequately.

Animals

Animals (e.g., birds and rodents) and insects may also contaminate food products with

Salmonella. It is possible for animal fecal contamination within and outside the

establishment to be introduced into the RTE production area.

Best Practices to Prevent Hazards from Animals

• Maintaining an effective pest control program to maintain sanitary conditions and

ensure that product is not adulterated (9 CFR 416.2(a)). Rats, mice, birds, and

insects are sources of pathogen contamination.

• Product and ingredients should always be protected from contamination and

adulteration during processing, handling, and storage (9 CFR 416.14).

Attachment A5. RTE

Salmonella

Self-Assessment

Tool

FSIS recommends that establishments use this tool to determine whether they have

adopted the appropriate procedures to control Salmonella, or whether they should adopt

new procedures. If establishments find that they are not meeting the recommendations

in this guideline, FSIS recommends they consider changing practices to better control

Salmonella in the product.

The questions are related to evaluating the following:

• Hazard Analysis/HACCP Plan

• Ingredients

• Corrective Actions in Response to Salmonella Positives

Hazard Analysis/HACCP Plan

YES

N/A

1. Have you considered whether Salmonella is a

hazard reasonably likely to occur (RLTO) in your

Hazard Analysis?

□

2. If you determined that Salmonella was RLTO, did

you establish CCPs to control or prevent it?

□

3. If you established CCPs, do you have sufficient

supporting documentation to support the

effectiveness of the measures you are taking?

□

4. If you produce roast, cooked, or corned beef, does

your process achieve at least a 6.5-Log or other

supportable (e.g., 5-Log) reduction of Salmonella?

□

5. If you produce cooked uncured meat patties, does

your process achieve at least a 5-Log reduction of

Salmonella?

□

6. If you produce cooked poultry, does your process

achieve at least a 7-Log reduction of Salmonella?

□

7. If you produce other cooked RTE meat products,

does your process achieve at least a 6.5-Log or

other supportable (e.g., 5-Log) reduction of

Salmonella in the product?

□

8. If you are using an alternative lethality Log

reduction target (e.g., 5-Log reduction) do you

have additional support such as COA, LOG,

combined interventions, or baseline testing?

□

9. As part of your critical limits, have you identified

the target or performance standard that your

□

process is designed to achieve (9 CFR

417.2(c)(3))?

10. If you produce cooked products and use a time-

temperature table, are you applying humidity

during the cooking process?

□

11. If “no” to the question above, do you have support

for why relative humidity is not a critical operating

parameter?

□

12. If “no” to the question above, are you applying a

scientific gap for lack of relative humidity? Which

one? (fill in here)

□

13. If you produce cooked products and use a FSIS

time-temperature table, have you limited product

heating come-up-time (50 to 130°F) to 6 hours or

less?

□

14. If “no” to the question above, do you have

alternative support for applying a long come-up-

time?

□

15. If “no” to the question above, are you applying a

scientific gap for long come-up-time?

□

Ingredients

YES

N/A

16. Do you add ingredients to the product after the

lethality treatment? (if “no,” move to the next

section)

□

17. Do you maintain COAs, LOGs, or other

information (e.g., sampling data) to support the

safety of the ingredients?

□

18. If you use LOGs, do they indicate how each lot of

ingredients is processed, tested, or otherwise

treated to ensure its safety?

□

19. Are the ingredients that you add to the product

included in your flow chart or hazard analysis?

□

20. If you use pre-packaged ingredients that are

included in the final package with the finished

product do you have LOGs or other information to

support their safety?

□

Corrective Actions in Response to Salmonella Positives

YES

N/A

21. Has a RTE product sample tested positive for

Salmonella from FSIS or establishment testing? (If

“no” the assessment is complete).

□

22. If you control Salmonella in your HACCP plan, did

you take corrective actions according to 9 CFR

417.3(a)? (If you prevent Salmonella through a

Sanitation SOP or other prerequisite program, skip

to #26).

□

23. Did you take steps to identify and eliminate the

cause of the deviation, according to 9 CFR

417.3(a)(1)?

□

24. If the cause of the positive result is under-

processing, did you immediately review your

processing system and bring the process back

into compliance?

□

25. If the cause of the positive result is lack of support

for your lethality process, did you change your

process or provide additional support for the

safety of the process, in light of the positive result?

□

26. If you prevent Salmonella through a Sanitation

SOP or another prerequisite program, did you take

corrective actions according to 9 CFR 417.3(b)?

□

27. As part of your corrective actions, did you

reassess your HACCP plan according to 9 CFR

417.3(b)(4)?

□

28. As a result of your reassessment, did you address

the pathogen in a CCP or make substantive

changes to your prerequisite program?

□

Attachment A6. Cooking Country-Cured Hams

In October 2018, an establishment recalled cooked country-cured ham product that was

associated with a listeriosis outbreak (Recall 084-2018; CDC: Outbreak of Listeria

Infections Linked to Deli Ham). FSIS’s investigation at the establishment found that the

country-cured hams were cooked in a sealed bag multiple times. Before being cooked

multiple times, the ham was salt-cured and dried, thus reducing its water activity.

Additionally, after an initial cooking step in a sealed bag, the ham was removed, drained

of its juices, and placed into a second bag; during this process, the ham may have been

cross-contaminated from the processing environment. Additionally, the draining of

juices may have resulted in drier conditions during cooking. The establishment used

FSIS cooking guidance (Appendix A) as scientific support that cooking achieved

lethality of pathogens, including Lm. However, as discussed on page 12, Appendix A

guidance was not intended for lower water activity products cooked under dry conditions

or for dried products cooked multiple times. Hence the process may not have been

lethal to Lm (USDA/FSIS, 2020). Establishments that apply these types of processes

must identify other support for their HACCP System (9 CFR 417.5(a)(1) and 9 CFR

417.4(a)(1)).

During the outbreak investigation, FSIS also discovered that several establishments

cook country-cured hams once under moist conditions using FSIS cooking guidance as

support. FSIS cooking guidance was also not intended for lower water activity products

cooked even under moist conditions; however, FSIS is not aware of any imminent food

safety issues with this practice. Therefore, page 47 (Table 5), includes critical operating

parameters that may be applied to cook dried products like country cured hams if they

are cooked once under moist conditions to rehydrate the surface. While cooking under

moist conditions should rehydrate the surface, there is no research validating this

process so it is considered a scientific gap. As with other scientific gaps, there is a

vulnerability because FSIS’s lethality guidance is not designed for processes where the

drying step comes before the moist cooking step. This is because cooking under low

moisture conditions results in product with a lower water activity. These conditions lead

to pathogens, such as Lm, becoming more heat-tolerant and the organism could survive

the cooking process. To minimize this vulnerability, FSIS recommends:

If the product is cooked once:

• Establishments should gather support such as water activity measurements

after drying (before cooking), then again after cooking to demonstrate that the

water activity increased, and product surface was rehydrated during cooking.

This recommendation applies even if the product is cooked-in bag, because

the water activity may not be high enough to ensure that pathogens are killed

on the product without addition of moisture.

• Establishments should achieve the highest water activity possible during

cooking. Values ≥ 0.96 have been shown to prevent bacterial heat tolerance

(Kieboom, et al. 2006), but this water activity may not be possible for all

processes to achieve.

• Establishments conduct finished product testing for Salmonella and Lm as part of

on-going verification.

Establishments should also ensure that the cooking bag is completely sealed, so that

moisture is contained in the bag and the product is not exposed to the environment or

contaminants. Cooking bags may be compromised during steps such as molding or

shaping. The establishment should have a process to verify the package integrity, and

if leaks are observed, the establishment should reprocess/recook the product, using a

supported process.

https://www.fsis.usda.gov/contact-us/askfsis

FSIS/USDA

www.fsis.usda.gov

2021