Lethality, Stabilization and Multiple Hurdles 

10/27/2021 

LETHALITY, STABILIZATION, AND MULTIPLE HURDLES 

Objectives 

After completion of this module, the participant will be able to: 

1. Define the following terms and explain their significance to the RTE food 

safety system: 

a. Lethality 

b. Stabilization 

c. Performance standard 

d. Target 

e. Water activity (aw) 

f. Critical operational parameters 

2. State the regulatory lethality and stabilization performance standards for 

cooked beef, and for cooked poultry, per 9 CFR 318.17 and 381.150. 

3. State the compliance guidelines frequently used to support lethality, 

stabilization and multiple hurdle in the establishment’s food safety systems. 

4. Identify the critical operational parameters described in the lethality 

compliance guideline for cooking beef and poultry. 

5. Describe the relationship between humidity and cooking temperatures as it 

pertains to the destruction of Salmonella. 

6. Describe the food safety significance of untreated or untested ingredients 

added to RTE products after the lethality step. 

7. Identify which microorganisms are controlled with the critical operational 

parameters provided in the stabilization compliance guideline. 

8. Explain the food safety significance of drying in the jerky process, and state 

the target pathogen controlled by this step. 

9. Explain how multiple hurdles are used in a food safety system. 

10. Identify at least four common factors used in the multiple hurdles concept. 

11. Describe the food safety significance of the fermentation step in a dry 

sausage process, and identify the pathogen of concern at this step. 

12. Recognize the purpose of the options developed by the Blue Ribbon Task 

Force. 

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13. Identify the critical operational parameters measured when establishments 

use the degree-hour limit to support a dry sausage process. 

14. Describe how inspectors verify that establishments have support for their 

lethality, stabilization and multiple-hurdle food safety systems. 

References 

1. FSIS Directive 7111.1, Rev. 2 - Verification Procedures For Lethality and 

Stabilization 

2. FSIS Directive 5000.1, Rev. 6 - Verifying an Establishments’ Food Safety 

System 

3. FSIS Directive 5000.6, Rev. 4 - Performance of the Hazard Analysis 

Verification 

(HAV) Task 

4. 9 CFR Part 318.17 - Requirements for the production of cooked Beef, 

roast beef, and cooked corned beef products 

5. 9 CFR Part 318.23 - Heat-processing and stabilization requirements for 

uncured meat patties 

6. 9 CFR Part 381.150 - Requirements for the production of fully cooked 

poultry products and partially cooked poultry breakfast strips 

7. 9 CFR 417 - Hazard Analysis and Critical Control Point (HACCP) Systems 

Introduction 

Ready-to-Eat Foods products are meat or poultry products that are edible without 

additional preparation to achieve food safety. Two main processes which are 

critical for achieving safety in RTE products are known as lethality and 

stabilization. They are used to control the biological hazards in RTE products. 

The lethality treatment is defined as the process step or steps used to destroy 

pathogenic microorganisms in a product to make the product safe for human 

consumption. FSIS expects that establishments will use a process that ensures 

that no Salmonella organisms remain in the finished product. The most common 

lethality treatment is heating the product. 

After the product is cooked, spores of Clostridium botulinum and Clostridium 

perfringens that survive the cooking process can germinate, becoming vegetative 

cells that can multiply to hazardous levels if cooling is inadequate. The processes 

that establishments employ to limit the growth of spore-forming bacteria are 

called stabilization. The most common stabilization is cooling. However, other 

treatments, such as adjusting the product pH (fermentation or marinating), 

reducing the water activity (drying or salt-curing), or adding antimicrobials; may 

be used in combination with heating or each other to destroy pathogens. 

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When multiple treatments are used in to achieve lethality or stabilization, it is 

referred to as the multiple hurdle approach. The multiple hurdle approach is 

often used to produce shelf-stable products. 

Shelf-stability is the condition achieved when meat and poultry products can be 

stored under ambient temperature and humidity conditions; if the package 

integrity is maintained during storage, shipping, and display at retail and in the 

home; and the product will not spoil or become unsafe throughout the 

manufacturer’s specified shelf-life. 

In this module, the different steps establishments use to achieve product safety 

will be discussed, along with the types of scientific supporting documentation 

establishments may have to support their decision-making. 

Public Health Concerns for RTE 

FSIS considers any RTE product to be adulterated if it contains pathogens of 

public health concern, or their toxins that can cause illness in humans. There are 

some pathogens where any level would make the product adulterated (such as 

Salmonella, Listeria monocytogenes (LM) and STEC) because it would be 

injurious to health. Salmonella is considered the pathogen of concern because it 

has been traditionally associated with certain types of RTE products. Thermal 

destruction of Salmonella is generally considered adequate to also destroy the 

other pathogens of concern. 

There are other pathogens like C. perfringens which are only a public health 

concern when multiplication occurs at levels that could lead to toxin formation, 

which in such cases would indicate that the products were prepared, packed, or 

held under insanitary conditions. For C. perfringens, FSIS generally expects 

establishment processes to show less than 1 log growth, while for C. botulinum, 

conditions permitting any growth are a public health concern. 

Critical Control Points in RTE 

After an establishment conducts a hazard analysis and identifies one or more 

hazards as reasonably likely to occur in their process, the establishment needs to 

determine how it will control those hazards to prevent, eliminate, or reduce them 

to an acceptable level. The establishment has the flexibility to select and develop 

the CCPs as it determines appropriate, provided the CCP can be supported. The 

CCP is a process step or a point in the process where control can be 

applied in many food processes. 

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Many steps are commonly recognized as CCPs in various food processing and 

production systems. Steps necessary to achieve lethality and stabilization are 

commonly CCPs that many RTE processes such as RTE roast beef, ham, and 

cooked poultry depend on to eliminate or control hazards. Other processes such 

as those for fermented dry and semi-dry sausages depend on several control 

steps used in conjunction with each other, which is the multiple hurdle concept. 

The establishment may use a number of types of scientific documentation to 

support the development and justification for designating a particular step or 

point in the process as a CCP. For instance, many peer-reviewed journal articles 

support the use of antimicrobial interventions, such as organic acid rinses and 

hot water rinses, at certain steps in the slaughter process. Likewise, there is 

much scientific literature identifying cooking as a means of destroying pathogenic 

microorganisms and chilling as a means of preventing their growth. An 

establishment may provide an explanation of why a specific process step was 

selected and established as a CCP in a decision-making document. 

Lethality CCP Example 1: In a record separate from the hazard analysis, the 

establishment has documented the following decision at the cooking step. “The 

beef trimmings we receive for grinding will carry a certain amount of bacteria, 

both spoilage (e.g., Pseudomonas spp.) and pathogenic organisms (e.g., 

Salmonella spp., E. coli O157:H7, and L. monocytogenes). The amount and 

types of bacteria present will vary depending on the conditions at the slaughter 

and processing establishment from which the meat is received. Cooking is the 

step in processing our uncured beef patties that separates the raw material 

environment from the ready-to-eat environment. The raw patties move from the 

raw side though a continuous oven/CO2 tunnel into the cooked product side. The 

oven is properly maintained and the temperature distribution is checked 

bimonthly. We have adopted a hold time and internal temperature for cooking 

our patties from the table in section 318.23 of USDA’s regulations that reduces 

pathogens to non-detectable levels. The destruction of microbial pathogens is a 

food safety concern; thus, the cooking step will be addressed as a CCP in our 

HACCP plan.” 

Stabilization CCP Example 2: In a record separate from the hazard analysis, 

the establishment has documented the following decision at the chilling step. 

The rate of chilling for our frankfurters, wieners, and hot dogs is important. 

Although our products have been cooked sufficiently to destroy vegetative 

pathogens (e.g., Salmonella spp. and E. coli O157:H7) a low level of spores 

(e.g., Clostridium spp. and Bacillus spp.) will remain viable. Because of their 

small diameter, these products chill quickly. After cooking, the sausages are 

initially chilled and then moved into the holding coolers. The temperature of the 

sausages is reduced at a rate well within FSIS’s cooling guideline for cured 

products found in Appendix B Option 3. If the product does not chill at the 

required rate, the germination and outgrowth of microbial spores and the growth 

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of other microbes could occur. Thus, the rate of chilling is a food safety concern 

that will be addressed as a CCP in our HACCP plan. 

Combination CCP Example 3: The establishment has documented the 

selection of CCPs as part of a beef jerky hazard analysis as demonstrated below. 

Process Food Safety Hazard Likely to Basis Preventive CCP 

Step occur? measures 

Cooking/ B – Vegetative Yes Potential Apply heat Yes 

Lethality Pathogens (Salmonella, outgrowth of treatment in 

E. coli O157:H7) pathogens marination 

C – None solution to 

P – None eliminate 

vegetative cells 

Drying B – Growth of Yes Final product is Use of dehydrator Yes 

shelf-stable and to reduce the level 

Staphylococcus does not bear a of free water in 

“keep finished product 

refrigerated” 

aureus 

C – None 

P – None statement 

Supporting Documentation for Critical Limits 

The establishment must determine a food safety criterion or a critical limit that 

must be met for each control or preventive measure associated with a CCP. 

The critical limit determines whether the process is under control; it separates 

acceptable product from unacceptable product. As stated in 9 CFR 417.1, a 

critical limit is the maximum or minimum value to which a physical, 

biological, or chemical hazard must be controlled at a CCP to prevent, 

eliminate, or reduce to an acceptable level the occurrence of the identified 

food safety hazard. A critical limit is usually a measurement, reading, or 

observation such as a temperature, time, a product property such as water 

activity (aw) or acidity, a chemical property such as available residual chlorine or 

brine concentration, or the visual presence or absence of fecal material. 

Critical limits have been established for many of the CCPs that are identified for 

the processes that produce RTE meat and poultry products, either through 

regulatory requirements or through technical and scientific literature. Like with 

the designation of a particular step or point in the process as a CCP, the 

establishment may use a number of types of scientific documentation to support 

the development and selection of a critical limit. Such scientific supporting 

documentation may include FSIS regulatory requirements, FSIS Compliance 

Guidelines, scientific articles, challenge studies, or expert advice. Every critical 

limit must have supporting documentation that demonstrates it is sufficient to 

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eliminate, prevent or reduce the occurrence of the specific food safety hazard to 

an acceptable level. Establishments may evaluate several sources when 

determining the appropriate food safety criteria or critical limits that must be met 

at each CCP. 

Note: Like critical limits, critical parameters in prerequisite programs or other 

written procedures used to prevent a food safety hazard from being reasonably 

likely to occur in the establishment’s process must be supported. The 

establishment may use some of the documentation listed above to demonstrate 

that the critical parameters are sufficient to prevent the hazard from occurring. 

A more detailed description of some of the sources establishments use to 

support their lethality and stabilization critical limits is provided below. 

Establishing Critical Limits –FSIS Performance Standards and 

Targets 

Before establishing critical limits at each CCP in their processes, establishments 

should review FSIS regulations to determine if there are any regulatory 

requirements which apply to their product or process. Although an establishment 

has flexibility in designing its food safety system, if there is a specific 

regulatory requirement that applies to the product produced, the 

establishment’s food system must be designed to meet that regulatory 

requirement. 

According to 9 CFR 417.2(c)(3), establishments must design their critical limits 

to meet all applicable performance standards or targets. 

9 CFR 417.2(c)(3)—Critical limits shall, at a minimum, be designed to ensure 

that applicable targets or performance standards established by FSIS, and any 

other requirement set forth in this chapter pertaining to the specific process or 

product, are met. 

As stipulated in 9 CFR 417.2(c)(3), establishments must ensure that the critical 

limits they incorporate into their HACCP plan at a CCP meet any applicable 

target or performance standard established by FSIS for the product they 

produce. Establishments that produce products subject to these regulations 

must have critical limits that are equivalent (equal to or more restrictive) to the 

times and temperatures specified in the regulation unless the establishment has 

requested and received a regulatory waiver. The directive that provides 

instructions for verifying lethality and stabilization process is FSIS Directive 

7111.1, Verification Procedures for Lethality and Stabilization. 

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Performance standards are quantifiable pathogen reduction levels or growth 

limit requirements set by FSIS for lethality and stabilization of certain products. 

Targets are quantifiable pathogen reduction levels or growth limits set by 

establishments to produce safe products in the absence of performance 

standards set by FSIS. Targets are used by establishments to demonstrate that 

the lethality and stabilization processes achieved by their food-safety systems 

prevent, eliminate, or reduce pathogens to acceptable levels. Establishments can 

choose to use Appendix A and B developed by FSIS or to identify and support 

their own targets. 

Waivers Establishments may submit a waiver per 9 CFR 303.1(h) to use a 

process that varies from a regulatory requirement, including performance 

standard requirements. More information about waivers can be found in FSIS Directive 

5020.1, Verification Activities for the Use of New Technology in Meat and Poultry 

Establishment and Egg Products Plants. 

For certain ready-to-eat (RTE) products, FSIS has established regulatory 

performance standards because they have a higher public health risk. These 

products have historically been associated with food borne illnesses caused by 

specific pathogenic bacteria or their toxins (Salmonella, L. monocytogenes, E. 

coli O157:H7, C. perfringens and C. botulinum). For instance, there have been: 

• Salmonellosis food borne illness outbreaks associated with cooked beef, 

roast beef, corned beef and cooked poultry products, 

• Listeriosis food borne illness outbreaks associated with post lethality 

exposed RTE products, 

• E. coli O157:H7 food borne illness outbreaks associated with uncured 

undercooked meat patties, and 

• C. perfringens food borne illnesses associated with temperature abused 

RTE products. 

The lethality performance standards require establishments to treat certain RTE 

products to ensure a specific log10 reduction of Salmonella microorganisms. 

Remember from the food microbiology module, that 1-log10 reduction means that 

the population of bacteria has been reduced by 90%. For example, a 5-log10 

reduction would reduce a population of 100,000 organisms to 1 organism. 

Heat treatment does not need to be the sole means by which the required 

lethality is achieved. For products that fall under a performance standard, heat 

treatment must be part of the lethality treatment. For example, establishments 

may use a combination of treatments such as the application of an antimicrobial 

agent to raw product to achieve a partial reduction in Salmonella organisms 

followed by the heat treatment to obtain the total reduction of Salmonella 

organisms required by the lethality performance standard 

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Alternative Lethality is a lethality treatment, other than ones prescribed in the 

regulations, that an establishment uses to meet performance standards. When 

using an alternative lethality, the establishment should ensure that its HACCP 

system is validated to ensure that no viable Salmonella organisms remain in the 

finished product. More detailed information about verification of alternative 

lethality can be found in Directive 7111.1. 

The stabilization performance standard requires establishments to prevent the 

growth of spore-forming bacteria that can survive cooking and can grow 

during cooling. Stabilization refers to the process of cooling after the cooking 

step. After the product is cooked, spores of Clostridium botulinum and 

Clostridium perfringens can germinate, becoming vegetative cells that can 

multiply to hazardous levels if cooling is inadequate. 

• C. botulinum produces a toxin when it grows in the product. 

• C. perfringens produces a toxin when it goes from the vegetative form to 

the spore form in the person’s intestine after consumption. 

C. perfringens grows faster than other spore formers, like C. botulinum. Limiting 

the growth of C. perfringens also limits growth of other, slower growing sporeforming bacteria. 

Outbreaks have been associated with meat and poultry products when they have 

been held for excessive lengths of time at warm temperatures. Heat treatments 

that kill pathogenic microorganisms can create an ideal environment for the 

multiplication of spore-forming bacteria that survive cooking. In fact, they can 

thrive in warm product after competitive spoilage microorganisms have been 

eliminated. Because Clostridium perfringens can grow between 125.6°F and 

80°F it is particularly important that meat and poultry products are cooled within a 

reasonable amount of time so that the microorganisms are not given time to grow 

to hazardous levels. The best control to stabilize heat treated products is rapid 

cooling to reduce the amount of time the spores have to grow into cells. 

The addition of sodium nitrite (curing) and sodium erythorbate or ascorbate 

(both cure accelerators) reduce the risk because the presence of these 

ingredients inhibits Clostridium growth. 

There are many RTE products that are not specifically addressed with a 

regulatory performance standard. Establishments must consider the food 

safety hazards that are reasonably likely to occur in these processes and 

establish steps to prevent, eliminate or reduce those hazards to an acceptable 

level, per 9 CFR 417.2. FSIS expects establishments to include the lethality 

pathogen reduction targets, and stabilization log outgrowth controls for C. 

perfringens and C. botulinum, in its HACCP plan or supporting documentation. 

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Additional support. For products without specific stabilization regulatory 

performance standards, FSIS recommends establishments set a target to ≤1-log 

growth of C. perfringens in the product. Establishments may be able to support a 

target of ≤ 2-logs growth of if sufficient support is provided. To use a process 

that allows ≤ 2-logs growth, establishments should provide additional support. 

More detailed information about verification of additional support can be found in 

Directive 7111.1. 

FSIS Performance Standards and Targets 

If an 

establishment 

produces.... Then its lethality treatment... Then its stabilization treatment... 

Cooked beef Is to achieve a 6.5-log reduction Is not to allow multiplication of 

Roast beef of Salmonella. toxigenic microorganisms such 

Cooked as C. botulinum and no more 

corned beef NOTE: The regulations 9 CFR 

318.17(a)(1) allow

establishments to set targets 

using an alternative lethality that 

ensures no viable Salmonella 

organisms remain in finished 

product. FSIS recommends 

≥ 5-log reduction as an 

alternative lethality if 

establishments have additional 

support (e.g., testing of raw 

materials or a validated 

intervention). 

than 1-log multiplication of

C. perfringens per 

9 CFR 318.17(a)(2). 

NOTE: Establishments may 

submit a waiver per 9 CFR

303.1(h) to use a process that 

allows ≤ 2-logs growth C. 

perfringens provided there are 

additional controls in place to 

ensure safety of the product. 

RTE uncured Is to follow one of the Is not to allow multiplication of 

beef patties time/temperature combinations in

9 CFR 318.23(b)(1). These 

time/temperature combinations 

achieve a 5-log lethality of 

Salmonella in the product. 

toxigenic microorganisms such 

as C. botulinum and no more 

than 1-log multiplication of 

C. perfringens per 9 CFR 

318.23(c). 

NOTE: Establishments may 

submit a waiver to use a process 

that allows ≤ 2-logs growth of C. 

perfringens. 

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If an 

establishment 

produces.... Then its lethality treatment... Then its stabilization treatment... 

Other RTE Is to determine the food safety Is to consider the food safety 

cooked meat hazards that are reasonably likely hazards that are reasonably likely 

products to occur in its lethality process

and establish steps to prevent, 

eliminate, or reduce those 

hazards to an acceptable level 

(9 CFR 417.2(a)(1)). 

NOTE: FSIS recommends 

establishments set targets to 

achieve a 6.5 or 5-log reduction 

of Salmonella in their process. To 

use a 5-log reduction, 

establishments should provide

additional support. 

to occur in its stabilization 

processes and establish steps to 

prevent, eliminate, or reduce 

those hazards to an acceptable 

level (9 CFR 417.2). 

NOTE: FSIS recommends 

establishments set a target to 

≤1-log or ≤ 2-logs growth of C. 

perfringens in the product. To 

use a process that allows 

≤ 2-logs growth, establishments 

should provide additional support 

RTE shelf Is to consider the food safety Is to consider the food safety

stable meat hazards that are reasonably likely hazards that are reasonably likely 

products to occur in its lethality processes 

and establish steps to prevent, 

eliminate, or reduce those 

hazards to an acceptable level

(9 CFR 417.2). 

NOTE: FSIS recommends that 

establishments achieve 5-log 

reduction of Salmonella, a 5-log 

reduction of E. coli and sufficient 

reduction of Lm in their process, 

or an alternative lethality 

to occur in its stabilization 

processes and establish steps to 

prevent, eliminate, or reduce 

those hazards to an acceptable 

level (9 CFR 417.2). 

NOTE: FSIS recommends 

establishments allow ≤1-log or 

≤ 2-logs growth of C. perfringens 

in the product. To use a process 

that allows ≤ 2-logs growth, 

establishments should provide 

additional support. For shelfstable products, establishments

should limit the growth of 

S. aureus to ≤ 2.0 logs during the

process, especially during the 

drying step and ensure no growth 

of S. aureus can occur during 

storage. 

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If an 

establishment 

produces.... Then its lethality treatment... Then its stabilization treatment... 

RTE cooked Is to achieve a 7-log10 reduction Is not to allow multiplication of 

poultry of Salmonella or an alternative 

lethality to comply with

9 CFR 381.150(a)(1). 

toxigenic microorganisms such 

as C. botulinum and no more 

than 1-log10 multiplication of 

C. perfringens per 9 CFR 

381.150(a)(2). 

NOTE: Establishments may 

submit a waiver to use a process 

that allows no more than 2-logs 

growth of C. perfringens. 

RTE shelf Is to achieve a 7-log10 reduction Is to consider the food safety 

stable poultry of Salmonella or an alternative hazards that are reasonably likely 

products lethality to comply with 9 CFR 

381.150(a)(1). 

NOTE: The regulations allow 

establishments to set targets 

using an alternative lethality that 

ensures no viable Salmonella 

organisms remain in the finished 

product. FSIS recommends 

achieving ≥ 5-log reduction as an 

alternative lethality for shelfstable products. No additional 

support is needed to use this 

alternative lethality with shelfstable products. 

to occur in its stabilization 

processes and establish steps to 

prevent, eliminate, or reduce

those hazards to an acceptable 

level (9 CFR 417.2). 

NOTE: FSIS recommends 

establishments allow ≤1-log or 

≤ 2-logs growth of C. perfringens 

in the product. To use a process 

that allows ≤ 2-logs of growth, 

establishments should provide

additional support. For shelfstable products, establishments 

should limit the growth of 

S. aureus to ≤ 2.0 logs during the

process, especially during the 

drying step and ensure no growth

of S. aureus can occur during 

storage. 

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If an 

establishment 

produces.... Then its lethality treatment... Then its stabilization treatment... 

NRTE No lethality required, will be Must allow no multiplication of 

partially cooked by the consumer. toxigenic microorganisms such 

cooked and as C. botulinum and no more 

char-marked NOTE: Establishments should than 1-log10 multiplication of C. 

meat patties, ensure controls and preventative perfringens per 9 CFR 

and partially measures are in place to limit 318.23(c)(1) and 9 CFR 

cooked growth of Salmonella so that 381.150(b). 

poultry customary lethality processes 

breakfast (such as cooking) used by NOTE: Establishments may 

strips consumers will be adequate. submit a waiver to use a 

stabilization process that allows 

≤ 2-logs growth of C. perfringens

and no multiplication of 

C. botulinum. 

Other NRTE, No lethality required, will be Is to consider the food safety

heat treated cooked by the consumer. hazards that are reasonably likely 

not fully to occur in its stabilization 

cooked NOTE: Establishments should processes and establish steps to 

products other ensure controls and preventative prevent, eliminate, or reduce 

than partially measures are in place to limit those hazards to an acceptable 

cooked and growth of Salmonella so that level (9 CFR 417.2). 

char-marked customary lethality processes 

patties and (such as cooking) used by NOTE: FSIS recommends 

partially consumers will be adequate to establishments allow ≤ 1-log or 

cooked eliminate the food safety hazard. ≤ 2-logs growth of C. perfringens 

poultry in the product. To use a process 

breakfast that allows ≤ 2-logs of growth, 

strips establishments should provide 

additional support. 

Establishments should also limit 

the growth of S. aureus to ≤ 2.0

logs during the process. 

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FSIS Compliance Guidelines 

FSIS has issued compliance guidelines for certain processes. They are 

published to provide guidance and information to the industry, especially small 

and very small establishments. The compliance guidelines are not regulatory 

requirements. Establishments may use the compliance guidelines to support the 

selection and development of the critical limits incorporated into their HACCP 

plans or critical parameters incorporated into a prerequisite program when they 

do not wish to use custom processes that require additional research or effort to 

generate the data necessary to support the critical limit or parameter. 

Establishments are not required to support their critical limits or parameters with 

the compliance guidelines. They may provide other types of data or 

documentation that supports the safety of their processes. Examples of FSIS 

compliance guidelines include: 

• Appendix A - FSIS Salmonella Compliance Guidelines for Small and Very 

Small Meat and Poultry Establishments that Produce Ready-to-Eat (RTE) 

Products and Revised Appendix A (Includes Appendix A, TimeTemperature Tables for Cooking RTE Poultry Products, and the 5-log 

Table), 

• Compliance Guideline: Lebanon Bologna, 

• Compliance Guidelines for Jerky, and 

• Appendix B - FSIS Compliance Guideline for Stabilization (Cooling and 

Hot-Holding) of Fully and Partially Heat Treated RTE and NRTE Meat and 

Poultry Products Produced by Small and Very Small Establishments and 

Revised Appendix B. 

If the establishment uses an FSIS compliance guideline for selecting and 

establishing its CCPs and critical limits, it must have a copy of that guideline in its 

records to support its decision. The compliance guideline is sufficient scientific 

and technical supporting documentation to meet the requirement in 9 CFR 

417.5(a)(2). The following are critical compliance guidelines. 

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Appendix A - Lethality Guideline - FSIS Salmonella Compliance Guidelines 

for Small and Very Small Meat and Poultry Establishments that Produce 

Ready-to-Eat (RTE) Products and Revised Appendix A 

FSIS consolidated much of the advice for establishments regarding production of 

RTE products into this document by incorporating the time-temperature table for 

meat products (Appendix A), the 5-log Table, and the Poultry Time-Temperature 

Tables as scientific support for a lethality treatment. These guidelines also 

discuss: 

• Salmonella contamination in RTE products may occur in the postprocessing environment. In several recent cases, Salmonella has been 

associated with the addition of untreated ingredients added after the 

lethality step. Establishments that add ingredients after lethality should 

have support that each lot used is tested, treated, or otherwise processed 

for safety. 

• During initial validation, establishments should identify all of the critical 

operational parameters (e.g., percent salt or fat, pH, water activity, 

humidity, pressure, etc.) identified in the scientific supporting 

documentation that may influence the effectiveness of the process. During 

the initial validation period, the establishment should verify that they are 

able to implement all of the critical operational parameters as used in the 

scientific support in order to ensure that the process can be successfully 

implemented in their own system. 

If the lethality guideline/Appendix A is used as supporting documentation for the 

selection of CCP and critical limits, all the conditions of Appendix A must be 

addressed. 

As shown below, the lethality guideline/Appendix A contains a table with two 

columns that have time and temperature combinations for preparing cooked 

beef, roast beef and cooked corned beef. These temperatures are product 

temperatures – minimum internal temperatures. One column of time and 

temperature combinations meets the performance standard by achieving a 6.5- 

log10 reduction of Salmonella. The time and temperature combinations in the 

other column achieve a 7.0-log10 reduction of Salmonella. These time and 

temperature combinations are included as a guide for establishments that want 

to process these beef products to exceed the required minimum 6.5-log10 

reduction and add an additional measure of safety. As shown in the table below, 

time and temperature combinations range from 130°F internal temperature for a 

minimum of 112 minutes to 158°F instantaneous internal temperature to achieve 

a 6.5-log10 reduction in Salmonella for beef products. 

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Excerpt from FSIS lethality compliance guideline - Appendix A Compliance

Guidelines for Meeting Lethality Performance Standards for certain Meat Products 

Meat products can be prepared using one of the follow ing time and temperature combinations. The 

stated temperature is the minimum that must be achieved and maintained in all parts of each piece of 

meat for a least the stated time. Establishments should apply humidity when using this table or 

additional support should be provided for the process. 

Degrees Fahrenheit Degrees Centigrade 6.5-log10 Lethality 7-log10 Lethality 

130 54.4 112 min. 121 min. 

131 55.0 89 min. 97 min. 

132 55.6 71 min. 77 min. 

133 56.1 56 min. 62 min. 

134 56.7 45 min. 47 min. 

135 57.2 36 min. 37 min. 

136 57.8 28 min. 32 min. 

137 58.4 23 min. 24 min. 

138 58.9 18 min. 19 min. 

139 59.5 15 min. 15 min. 

140 60.0 12 min. 12 min. 

141 60.6 9 min. 10 min. 

142 61.1 8 min. 8 min. 

143 61.7 6 min. 6 min. 

144 62.2 5 min. 5 min. 

145 62.8 4 min. 4 min. 

146 63.3 169 sec. 182 sec. 

147 63.9 134 sec. 144 sec. 

148 64.4 107 sec. 115 sec. 

149 65.0 85 sec. 91 sec. 

150 65.6 67 sec. 72 sec. 

151 66.1 54 sec. 58 sec. 

152 66.7 43 sec. 46 sec. 

153 67.2 34 sec. 37 sec. 

154 67.8 27 sec. 29 sec. 

155 68.3 22 sec. 23 sec. 

156 68.9 17 sec. 19 sec. 

157 69.4 14 sec. 15 sec. 

158 70.0 0 sec.** 0 sec.** 

159 70.6 0 sec.** 0 sec.** 

160 71.1 0 sec ** 0 sec.** 

** The required lethalitiesare achieved instantly when the internal temperature ofa cooked meat product reaches 

158o F or above. 

Other product process may use Appendix A - Although there are no specific 

lethality performance standards for other fully cooked meat products (such as, 

cooked pork with barbeque sauce) they may also be processed following the 

Guidance in Appendix A to achieve a 6.5 log10 lethality. Therefore, 

establishments may use Appendix A to support their critical limits applied at the 

cooking or heat treatment CCPs in HACCP plans for other types of RTE meat, 

including pork. 

Humidity in Appendix A – In addition to time and temperature, humidity is 

another critical factor in Appendix A, which establishments often overlook. High 

relative humidity during the cooking of meat or poultry is a critical parameter for 

ensuring the lethality of pathogens and producing RTE products. If adequate 

humidity is not maintained during heating, the product surface will not heat as 

quickly and the surface can dry out. In addition, surface drying may concentrate 

solutes such as sugar and salt. Bacteria can become more heat resistant as 

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their moisture level decreases, and increased concentrations of solutes, 

especially sugars, can also increase the heat resistance of bacteria. So, if the 

product surface dries out before the pathogens are destroyed their heat 

resistance increases and enhances their ability to survive heating. 

Options for maintaining relative humidity in Appendix A include, for meat or 

poultry products of any size, when the cooking time is at least 1 hour and 

process temperature is above 145°F: 

• Introducing steam for 50% of the cooking time but not less than 1 hour. 

• Sealing the cooking unit or oven for 50% of the cooking time but not less 

than 1 hour. 

• Introducing steam to achieve humidity at 90% for at least 25% of the 

cooking time or 1 hour. 

The relative humidity levels suggested in Appendix A do not apply to all heat 

processes applied to meat and poultry products. The humidity levels only apply 

to heat processes that can evaporate moisture from the surface of the product, 

for example, large mass products like beef briskets and rounds where surface 

drying can occur before the destruction of the pathogen. 

For some heat processes, humidity around the product is inherently 

maintained and does not have to be added or monitored. Such processes 

include, but are not limited to: 

• Immersing the product in a liquid cooking medium, 

• Cooking the product in a sealed, moisture impermeable bag (e.g., cook-inbag meat or poultry), 

• Applying direct heat, such as a grill, heating coil, flame, or rotisserie, which 

heats the surface rapidly enough to attain a lethal effect before 

evaporation or surface cooling occurs, and 

• Using a product casing – almost all casings will prevent or inhibit moisture 

loss, so that the heat resistance of pathogens is not affected during the 

cooking process (e.g., sausages cooked in casings). 

Humidity also does not need to be addressed when establishments heat meat or 

poultry products that are 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 Appendix A or the Poultry Time-Temperature Tables. 

If an establishment uses Appendix A as support, and humidity is not added 

during the process or maintained by the process, it needs to provide additional 

scientific and technical supporting documentation to demonstrate that the heat 

treatment adopted in its HACCP plan is effective in controlling the identified 

hazard. 

Heating come up time - If meat or poultry products are slow cooked, the 

cooking come-up time (time it takes to reach the final internal temperature), 

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should be no more than 6 hours between 50-130°F to ensure that S. aureus 

growth is limited when establishments are using FSIS Appendix A, the 5-log 

Table, or the Poultry Time-Temperature Tables as scientific support for a lethality 

treatment. Additional support may be provided that demonstrates come up times 

longer than 6 hours, for example, in hams, do not result in S. aureus growth > 2 

logs 

Heating Deviations 

Establishments must perform corrective actions in response to a heating 

deviation per 9 CFR 417.3. Appendix A addresses heating deviations such as 

slow come-up times and long dwell times. Depending on the circumstances, 

establishments may want to use a validated microbial pathogen computer 

modeling (MPCM) program to estimate the relative growth of pathogenic 

bacteria. However, establishments may want to rely upon the expertise of a 

processing authority to determine the severity of heating deviations and 

subsequent appropriate disposition of the product in question. Dwell times of 

greater than 6 hours in the 50°F to 130°F range are especially hazardous not 

only because pathogenic microorganisms have optimal conditions to grow but 

also because certain toxigenic bacteria like S. aureus can produce heat stable 

toxins that are not inactivated by normal re-cooking procedures. 

Instantaneous Temperatures in Lethality Guideline for Cooked Poultry 

The performance standard for fully cooked poultry products requires a 7.0- log10 

reduction in Salmonella. The lethality compliance guideline, in the section on 

poultry, contains one temperature each for cooking uncured poultry (160oF) and 

for cooking cured poultry (155oF) to achieve the required 7.0-log10 reduction in 

Salmonella. These are final internal product temperatures. Humidity should be 

maintained when cooking poultry products. 

Time-Temperature Tables for Cooking RTE Poultry Products 

Studies have shown that there is a difference in bacterial resistance due to the 

type of product species. A separate section of the lethality compliance guideline, 

Time-Temperature Tables for Cooking Ready-To-Eat Poultry Products, contains 

time and temperature combinations for fully cooking chicken and turkey. 

The Poultry Time-Temperature Tables, included in the lethality compliance 

guideline, provide establishments with time and temperature combinations that 

can be used to cook chicken and turkey products with 1 to 12% fat levels. These 

processes achieve the required 7.0-log10 reduction of Salmonella. The time and 

temperature combination table for chicken and turkey that contains 7% fat is 

given below. When using the Poultry Time-Temperatures tables, establishments 

should consider the use of humidity. 

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Excerpt from Time and Temperatures for Cooking RTE Poultry 

Times for giv en temperature, fat lev el, and speciesneeded to obtain 7- log10 lethalityof Salmonella* 

7% Fat 

Temperature (° F) Time for Chicken Time for Turkey 

136 71.4 min 66.3 min 

137 56.8 min 54.1 min 

138 45.3 min 44.2 min 

139 36.2 min 36.2 min 

140 29 min 29.7 min 

141 23.2 min 24.4 min 

142 18.7 min 20.1 min 

143 15.1 min 16.6 min 

144 12.2 min 13.7 min 

145 9.8 min 11.3 min 

146 7.9 min 9.2 min 

147 6.3 min 7.5 min 

148 5 min 6.1 min 

149 3.9 min 4.9 min 

150 3 min 3.9 min 

151 2.2 min 3 min 

152 1.7 min 2.3 min 

153 1.3 min 1.9 min 

154 1 min 1.5 min 

155 49.5 sec 1.2 min 

156 39.2 sec 1 min 

157 31 sec 49.2 sec 

158 24.5 sec 40 sec 

159 19.4 sec 32.4 sec 

160 15.3 sec 26.3 sec 

161 12.1 sec 21.4 sec 

162 9.6 sec 17.3 sec 

163 < 10.0 sec 14.1 sec 

164 < 10.0 sec 11.4 sec 

165 < 10.0 sec < 10.0 sec 

* The required lethalitiesare achieved instantly at the internal temperature in which the holding time is< 10 

seconds. The application of relative humidity asoutlined inAppendix A, if applicable, must be considered. 

The nature of the product in which a microorganism is heated can affect the way 

the product heats and the heat resistance of the microorganism. Product 

attributes such as fat content, water activity (aw) and pH, and added ingredients 

such as nitrite and organic acids can increase or decrease the heat resistance of 

microorganisms. Fat acts as an insulator that decreases the rate of heating; thus 

the higher the fat content, the longer it takes to get the same level of destruction 

of the microorganism. This fact is reflected in the time and temperature 

combination guidelines. The guidelines provide separate tables for various 

percentages of fat. 

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Appendix B - FSIS Compliance Guideline for Stabilization (Cooling and HotHolding) of Fully and Partially Heat-Treated RTE and NRTE Meat and 

Poultry Products Produced by Small and Very Small Establishments and 

Revised Appendix B 

FSIS requires establishments that produce RTE roast beef, cooked beef and 

corned beef products, fully cooked, partially cooked, and char-marked meat 

patties, and certain partially cooked and ready-to-eat poultry products to meet the 

stabilization performance standards for preventing or inhibiting the growth of 

spore-forming bacteria contained in 9 CFR 318.17, 318.23, and 381.150. 

Appendix B can be used for support for all meat and poultry product chilling 

processes. And as with all of the published compliance guidelines, 

establishments are not required to use Appendix B, establishments are free to 

develop or identify other scientific or technical support for chilling critical 

operational parameters. 

Continuous cooling through the given temperature range is very important. 

Excessive dwell time in the range of 130° to 80°F is especially hazardous 

because it allows rapid growth of Clostridia. Therefore, cooling between these 

temperature control points should be as rapid as possible. 

Appendix B has four different time and temperature combinations for cooling. 

Appendix B - Option 1 

The internal temperature of the product is cooled: 

• from 130°F to 80°F in 1.5 hours, and 

• from 80°F to 40°F in 5 hours. 

This cooling option can be applied universally to all fully cooked and small mass 

heated-treated but not fully cooked (NRTE) meat and poultry products that are 

uncured or cured and that receive an initial lethality treatment that eliminates all 

vegetative C. perfringens. 

With regard to partially cooked products, FSIS has specific cooling requirements 

for certain small mass products in its regulations. These products are partially 

cooked meat patties, char-marked meat patties (9 CFR 318.23(c)(1)), and 

partially cooked poultry breakfast strips (9 CFR 381.150(b)). The time and 

temperature combinations in option 1 can be applied to cool these products. 

However, the “come-up” time to the final heating temperature should be 1 hour or 

less. Because partial cooking processes may not destroy all vegetative cells of 

C. botulinum, C. perfringens, and B. Cereus, partially cooked meat and poultry 

products may not be safe unless the establishment accounts for the cumulative 

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growth of these pathogens during the heating (partial cook) and cooling steps. 

Because the hazard may grow during a slow “come-up” time and/or slow cooling 

process, the degree of hazard depends on the establishment’s time and 

temperature control at the heating and cooling steps. 

Appendix B – Option 1 Example: An establishment’s hazard analysis identified 

the growth of C. botulinum and C. perfringens spores as hazards likely to occur 

during chilling, and therefore identified the chill step as a CCP for its Oven 

Roasted Chicken Breast operation. It determined that an appropriate 

performance standard for the chilling step is to prevent the growth of C. 

botulinum and to limit the growth of C. perfringens to no more than a 1-log10. The 

establishment selected this performance standard because it is the stabilization 

performance standard FSIS recommends for all fully cooked RTE meat and 

poultry products. The establishment decides to incorporate the appropriate 

cooling time and temperature combinations in Appendix B to establish the chilling 

CCP for its Oven Roasted Chicken Breast (product cooled from 130°F to 80°F in 

1.5 hours or less and from 80°F to 40°F in 5 hours or less.) The establishment 

places a copy of Appendix B in the supporting documentation file. 

Appendix B - Option 2 

Chilling of the product: 

• begins within 90 minutes after the end of the cooking step. 

The internal temperature of the product is cooled from: 

• 120°F to 80°F in 1 hour, 

• 80°F to 55°F in 5 hours, and 

• chilling continues until internal temperature of the product reaches 40°F. 

This option applies to: 

• Fully cooked products, meat or poultry 

• Products may be cured or uncured 

The establishment does not need to monitor the temperature drop from 120°F to 

80°F for every stabilized lot of product, if data has been gathered during initial 

validation and as part of ongoing verification to support the critical operational 

parameters of this option can be met. Conditions affecting consistent cooling 

include cooler load (the amount of product in the cooler), the cooler temperature 

and air flow rate, and the product’s size, shape and weight. 

Appendix B - Cured Products - Option 3 

Establishments cooling cured RTE products have another option. To use the 

third stabilization option, establishments should ensure that at least 100 ppm 

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nitrite is added from either a purified or natural source along with at least 250 

ppm of ascorbate or erythorbate as a cure accelerator. 

Products may be cooled so that the internal temperature of the product is 

reduced: 

• from 130°F to 80°F in 5 hours, and 

• from 80°F to 45°F in 10 hours (15 hours total cooling time). 

This cooling method provides a narrow margin of safety. If a cooling deviation 

occurs, an establishment should assume that their process has exceeded the 

performance standard for controlling the growth of C. perfringens and take 

corrective action. The presence of the nitrite and salt, however, should ensure 

compliance with the performance standard for C. botulinum. 

Note: Natural sources of nitrite are not approved as curing agents, so product 

containing only natural sources of nitrite such as celery powder are considered 

uncured for labeling purposes. Establishments using natural sources of nitrite 

(and ascorbate) can, however, use these ingredients as antimicrobials for the 

purposes of following the third stabilization option. To use the third stabilization 

option, establishments should ensure that at least 100 ppm nitrite is added from 

the natural source along with at least 250 ppm of ascorbate or erythorbate as a 

cure accelerator and that the type and level of ingredients has been considered 

safe and suitable as antimicrobial agents per FSIS Directive 7120.1, Rev. 56. 

See AskFSIS questions “Use of celery powder and other natural sources of 

nitrite as curing agents” and “Appendix B: Stabilization Option 3 for products 

containing celery powder and other natural sources of nitrite.” 

Appendix B - Cured Products - Option 4 

This process may be used for the slow cooling of fully cooked meat and poultry 

products cured with nitrite or salt. During cooling, the products maximum internal 

temperature should not remain between: 

• 120°F to 40°F for more than 20 hours. 

The cooling process: 

• Causes a continuous drop in product temperature; or 

• Controls the products temperature so that it does not stay between 120°F 

and 80°F for more than 2 hours 

This option applies to fully cooked products formulated: 

• With greater than 40 ppm of sodium nitrite and a brine concentration (salt) 

of 6% or more, or 

• With or without nitrite, but with a maximum water activity of 0.92 

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The FSIS Compliance Guideline for Stabilization (Cooling and Hot-Holding) of 

Fully and Partially Heat-Treated RTE and NRTE Meat and Poultry Products 

Produced by Small and Very Small Establishments and Revised Appendix B also 

contains recommended cooling time and temperature parameters for 

establishments that have a waiver from the performance standard stabilization 

requirements to use a process that allows up to 2-logs growth of C. perfringens in 

the product or that chooses to support a target that allows up to 2-logs growth of 

C. perfringens for products that don’t fall under a waiver. 

Cooling Deviations 

Cooling deviations are also addressed in Appendix B. A cooling deviation is a 

situation when the established time intervals and temperatures are not met. The 

recommended time and temperature combinations in the guideline incorporate a 

small safety margin. Therefore, a small variation in meeting a time interval or 

temperature value by itself may not mean that the performance standard is not 

met. 

A part of corrective actions, establishments are required to determine the cause 

of all cooling deviations, no matter how small, per 9 CFR 417.3(a) and ensure 

measures are established to prevent recurrence. If the cause of each small 

cooling deviation is not identified and corrected when first noticed, the problem 

will likely recur and may become more severe. Repetitive deviations from the 

critical limits demonstrate the establishment is unable to control the process and 

should reassess as required by 9 CFR 417.4(b) and identify controls that can be 

implemented effectively. If cooling is addressed through a prerequisite programs, 

as part of corrective actions, establishments are required to reassess to 

determine whether the newly identified deviation or other unforeseen hazard 

should be incorporated into the HACCP plan. 

In the event that a cooling deviation occurs, a validated microbial pathogen 

computer modeling program program can be useful in assessing the severity of a 

cooling deviation. Unless a predictive modeling program has been validated for 

the meat or poultry product of interest, it is not appropriate to rely solely upon the 

model’s results to determine the safety of foods and processing systems. An 

example of a predictive model that has been validated for cured and uncured 

meat and poultry products is the ComBase Perfringens Predictor. 

While a validated predictive modeling program cannot provide an exact 

determination of the amount of Clostridial growth, it can provide a useful 

estimate. The more data points, such as time and temperature measurements, 

that are available, the more accurate the model. In addition, it is important that 

establishment input accurate pH and salt levels, if applicable. Product may be 

salvaged if the results of computer modeling can ensure product safety. 

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The Agency policy/guidance concerning the disposition of product for cooling 

deviations is listed below: 

• If no more than 1 log10 growth of C. perfringens and no C. botulinum 

growth (mean net growth ≤ 0.30 log10), then the process meets the 

stabilization performance standard or Agency policy and the product can 

be released. 

• If there is more than a 1 log10 growth of C. perfringens and no C. 

botulinum growth (mean net growth ≤ 0.30 log10), then product may be 

either: 

o Recooked or 

o Microbiologically tested (N ≥ 10) or 

o Destroyed 

• If there is greater than a 1 log10 growth of C. perfringens and > 0.30 log10 

increase of C. botulinum, then the product should be destroyed 

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Lethality and Stabilization Compliance Guidelines for Jerky 

Meat or poultry jerky is a RTE, dried product that is generally shelf-stable (it does 

not require refrigeration after proper processing). In general, jerky processing 

includes 8 steps: 

• Strip preparation, slicing or forming the meat or poultry, 

• Marination, 

• Interventions, 

• Surface preparation, 

• Heating, the lethality treatment, 

• Drying, the stabilization step, 

• Post-drying heat step, and 

• Handling and packaging. 

Heating and drying are critical steps. The purpose of the heating step is to apply 

a lethality treatment to kill or reduce the numbers of microorganisms, including 

pathogens. Drying the jerky stabilizes the final product and prevents the growth 

of microorganisms, especially toxigenic pathogens. 

In 2003, FSIS found that some meat and poultry jerky manufacturers might not 

be applying adequate heat processes to destroy pathogens and produce a safe 

product. Some of these establishments were located in dry parts of the country 

such as New Mexico, and product was produced under low humidity conditions 

which likely led to lower reductions in pathogenic microorganisms than expected. 

Some producers were applying dry heat to both heat treat and dry their jerky. As 

previously stated, the heating temperature and relative humidity during the 

cooking of meat and poultry are critical parameters for ensuring the lethality of 

pathogens. When high humidity is absent from the heating chamber most of 

heat is absorbed by the moisture evaporating from the product. The surface of 

the product will not reach a lethal temperature until most of the moisture is gone. 

In addition, if adequate humidity is not maintained or applied for the sufficient 

amount of time during the first part heating process, the product will lose 

moisture, which reduces the water activity (aw) of the product and increases the 

concentration of solutes in the product. The reduced aw and increased solute 

concentration increases the heat resistance of bacteria, including Salmonella. 

Thus, the amount of time needed at a particular temperature to destroy 

Salmonella increases. It is crucial that the processor prevent drying of the 

product until a lethal time and temperature combination is attained. 

FSIS also found that some jerky manufacturers were relying on the maximum 

moisture-protein-ratio (MPR), rather than aw, for determining whether their 

process adequately dried the jerky to produce a shelf-stable product. However, 

aw as measured by laboratory analysis is the more appropriate indicator to verify 

that the jerky is properly dried. Water activity is a better measure of available 

water for microbial growth than MPR. Minimizing available water by achieving a 

water activity aw that inhibits the growth of microorganisms is critical for stabilizing 

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jerky. An MPR of 0.75:1 or less is necessary to label the product “jerky,” but it is 

not sufficient to ensure a safe product. 

As a result of these findings, FSIS developed the “Compliance Guideline for Meat 

and Poultry Jerky Produced by Small and Very Small Plants” to provide guidance 

and information to small operators that manufacture jerky. The compliance 

guideline lists eight processing steps in the production of meat and poultry jerky. 

Although an establishment’s process may not include all of the steps, a lethality 

treatment step and drying step must be used to produce a safe product. Drying 

should closely follow heating. Some processors combine the heating and drying 

procedures into one step. In this case, it is critical that the heating step include 

adequate humidity to prevent the product from drying prematurely and slowing or 

stopping the lethality process before the jerky is dried. The lethality treatment 

and drying is discussed in more detail below. 

Jerky hazards—The establishment needs to control, reduce, or eliminate the 

biological hazards identified in its hazard analysis. For meat and poultry jerky, 

biological hazards will most likely include the microbiological hazards from 

Salmonella spp., L. monocytogenes, and S. aureus. For beef jerky, E. coli 

O157:H7 may also be a hazard reasonably likely to occur. In recent years, 

several jerky products have been found to be adulterated with Salmonella and E. 

coli O157:H7. 

Lethality treatment— Establishments may choose a number of different types of 

scientific documents to support the lethality time/temperature/humidity 

combination used in the actual process. The lethality treatment of meat jerky 

should achieve at least a 5.0 log10 reduction of Salmonella spp. and should also 

achieve sufficient reductions in the other bacterial pathogens of public health 

concern, for example, at least a 5.0 log10 reduction for E. coli O157:H7 for 

products containing beef as recommended in the RTE Salmonella Compliance 

Guidelines. 

The lethality treatment of poultry jerky should achieve at least a 5.0 log10 

reduction of Salmonella spp. Although poultry jerky is considered to fall under the 

performance standard in 9 CFR 381.150, the regulation allows for the use of an 

alternative lethality that achieves an equivalent probability that no viable 

Salmonellas organisms remain in the finished product. Research has supported 

that a 5.0 log10 reduction in Salmonella is sufficient for shelf-stable products. 

Establishments may use Appendix A or other FSIS compliance guidelines as 

support for their critical limit for the lethality treatment to ensure a safe product, or 

they may support their process using another type of scientific supporting 

documentation. It is important to note that the temperatures listed in Appendix A 

and the “Time-Temperature Tables” are product temperatures, not oven 

temperatures. Establishments may utilize published journal articles or develop 

customized processes that achieve an appropriate reduction of pathogens. A 

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number of journal articles are available showing validated processes for jerky. 

Whichever support they chose, establishments must implement all critical 

operational parameters into their process. The process must be validated; it 

must be based on scientific literature and supported by data showing the process 

can be implemented as designed in the establishment 

Relative Humidity - Time and temperature alone are not sufficient for an 

adequate lethality process. For meat and poultry jerky, relative humidity is also a 

critical operational parameter. Therefore, establishments should maintain the 

same level of relative humidity as is used in their scientific supporting 

documentation. 

If an establishment uses Appendix A or the Time-Temperature Tables for 

Cooking Ready-To-Eat Poultry Products as their scientific support than they are 

expected to following one of the humidity options provided. Humidity may be 

maintained by injecting steam or sealing the oven for 50% of the cooking or 

heating process time but not less than one hour, or controlling the relative 

humidity at 90% for the times listed in the guidelines, unless the establishment 

can provide additional scientific and technical documentation that the process 

can achieve an adequate lethality with less humidity or less time at 90% relative 

humidity. Note that the Appendix A humidity options to seal the oven or inject 

steam only apply to time/temperature combinations of 145°F for 4 minutes or 

above. 

Note: Establishments that are located at high elevations may need to increase 

the amount of moisture added to the smokehouse chamber to account for lower 

levels of humidity in the ambient air. Processing failures in the manufacture of 

jerky have occurred in establishments located at high altitudes. 

Establishments may use the following measures to aid in meeting the humidity 

parameters in Appendix A. 

 Seal the oven 

Close the oven dampers to provide a closed system and prevent moisture 

loss. This would meet the requirements of Appendix A provided that the oven 

remains sealed for 50% of the cooking/thermal process time and no less than 

1 hour. 

 Add humidity 

• Place one or more shallow, wide pans of hot water in the oven to provide 

humidity in the system. 

• Injecting steam or a fine water mist in the oven can also add humidity. 

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In either case, the use of a wet bulb thermometer, in addition to the dry bulb 

thermometer, would enable the operator to determine whether adequate 

humidity is being applied. 

The establishment is expected to maintain the relative humidity during the 

lethality treatment depending upon the humidity option it is following from the 

guidelines. In addition, establishments using any of the options in the Appendix 

A guidelines are also expected to either: 1) monitor the humidity level of their 

ovens (for example, 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 2) provide documentation that demonstrating that humidity is 

maintained in the ovens when the oven dampers are closed or steam is injected. 

An establishment should have a procedure for checking that the dampers are 

properly working if they are using documentation to support that the humidity is 

maintained in the ovens when the dampers are closed. 

Note: Some establishments may not monitor humidity at the same frequency as 

time and temperature. It is up to establishments to support the monitoring 

frequency and procedure per 9 CFR 417.5 (a)(1). IPP should be aware that 

establishments that choose a monitoring frequency less than each batch or lot 

should consider how they will support product safety in the event of a deviation if 

documentation is not available to support batches or lots of product produced 

since the last monitoring check demonstrated adequate humidity. 

Wet and Dry Bulb Measurements—When the heating unit does not provide a 

direct measurement of humidity, wet and dry bulb measurements can be used to 

determine relative humidity. A wet bulb thermometer can be prepared by fitting 

a wet, moisture-wicking cloth around a dry bulb thermometer. To maintain a wet 

cloth during the process, submerge an end of the cloth in some water. The cloth 

must stay wet during the entire cooking step and should be changed daily, 

especially if smoke is applied. Using a wet bulb thermometer is especially 

important when the facility is located at a high altitude or areas of low humidity 

with high evaporation rates. Relative humidity can be calculated from wet bulb 

and dry bulb readings. As long as proper humidity is maintained, according to 

the scientific support chosen, the level of pathogen reduction attained by using 

the lethality compliance guidelines for cooking poultry or whole beef is sufficient 

to produce a safe jerky product. 

Drying— After the lethality treatment, the product is dried to meet a water activity 

(aw) level that will stabilize the finished product for food safety purposes. The aw, 

not MPR, is the key to determining the proper level of drying. The aw can vary 

greatly at any given MPR due to the presence and level of different solutes, such 

as sugar and salt. Therefore, a laboratory analysis for aw should be used to verify 

proper drying. For labeling purposes, the finished product must also meet the 

MPR product standard. 

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A water activity of 0.85 or lower in the finished product should control the growth 

of S. aureus and any other pathogen of concern, as well as mold. 

Establishments that establish a maximum aw of 0.85 in the finished product as the 

critical limit at the drying step may use the jerky guidelines to support their 

decision. Vacuum packaging product in an oxygen impervious film creates an 

anaerobic environment where no oxygen is present, which adds an additional 

degree of safety. In these cases the water activity critical limit could be 0.91 or 

lower. These limits are based on the growth and toxin production limits for 

Staphylococcus aureus under optimal conditions with and without oxygen 

present (ICMSF, 1996). 

Mold growth, which is more of a quality than a food safety concern, may also be 

controlled by using antimicrobial interventions such as modified atmospheric 

packaging, adding oxygen scavengers to the package, or applying antimicrobial 

agents such as potassium sorbate or citric acid to the surface of the dried 

product. 

Note: Vacuum packaged products with a water activity level > 0.85 and ≤ 0.91

should be kept refrigerated once the package is opened because the product 

would no longer be considered shelf-stable once it is exposed to oxygen. This is 

mainly a concern for products that would not be consumed within a single serving 

as these products are not likely to be vacuum packaged by the consumer 

between servings. Therefore, unless the establishment has support that the 

product is likely to be consumed in a single serving, vacuum packaged products 

with a water activity in the range of > 0.85 and ≤ 0.91 should be labeled with a

statement such as “Refrigerate After Opening” (as described in 9 CFR 317.2(k)). 

Jerky Guideline Example 1: A very small establishment that produces poultry 

jerky products is in the process of developing its HACCP plan. It establishes an 

internal temperature of 160°F as the critical limit at the cooking CCP in its 

HACCP plan, which is supported by the jerky guidelines and Appendix A. The 

establishment is aware that premature drying of the product surface could result 

in inadequate destruction of pathogenic microorganisms; however, it decides not 

to include 90% humidity as a critical limit because the cooking unit cannot 

maintain that level of humidity. Instead, the establishment decides to state in the 

HACCP that the dampers on the smokehouse are closed during the lethality step 

for over one hour to seal the oven and prevent moisture loss within the chamber, 

which is consistent with Appendix A. It will monitor the humidity using a wet bulb 

thermometer during the lethality step and verify the presence of humidity in the 

smokehouse is maintained during at least 50% of the processing time and in no 

case less than one hour and record results. The functioning of the dampers will 

be checked as part of a smokehouse maintenance program. The establishment 

includes a copy of Appendix A, Compliance Guidelines for Meeting Lethality 

Performance Standards for Certain Meat and Poultry Products and the Jerky 

Guidelines in its supporting documentation file. 

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Jerky Guideline Example 2: A very small establishment that produces beef 

jerky products identified the growth of S. aureus as a hazard that is reasonably 

likely to occur over the shelf life of the product. A maximum aw of 0.82 is 

established as the critical limit at the drying step in the establishment’s HACCP 

plan. Since this aw is less than 0.85, it will prevent the growth of S. aureus during 

storage under aerobic condition (meaning it does not have to be vacuum 

packaged). At water activity < 0.93 growth of spore-formers is prevented which is 

why validated cooling is not needed. The establishment also addresses mold 

growth by using short inventory dates and is thus consistent with the Jerky 

Guidelines. The establishment includes a copy of the jerky guidelines in its 

supporting documentation file. 

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Multiple Hurdles 

Combinations of inhibitory factors that individually are insufficient to control 

microorganisms can often be effective. This has sometimes been referred to as 

the multiple hurdles concept – if enough hurdles or barriers are included, 

bacteria will not be able to overcome the hurdles and grow. For example, certain 

production processes are dependent on several parameters like salt, nitrite, and 

possibly other additives such as ascorbate/isoascorbate. 

The multiple hurdle approach is used for many fermented or shelf stable meat 

products. For example, a summer sausage process may involve a combination of 

curing chemicals such as nitrite and salt, reduced aw due to drying, reduced pH 

due to fermentation, and a mild heat process. This combination of hurdles results 

in a safe and shelf-stable product. The interaction of these factors affects specific 

microorganisms and chemical reactions. Controlling the various factors and 

interactions maximizes the total effect and achieves shelf-stability. 

Microbiological minimum or maximum limits for growth are primarily due to 

temperature, water activity, pH and/or the presence of preservatives. The 

published limits apply only when all other factors are optimal for growth of the 

specific microorganism. In actual practice, other conditions are not optimal, and 

therefore organisms will usually not be able to grow at the published minimum or 

maximum level of the growth-inhibiting factor. In dried meats, if more than one 

hurdle effect is present the effects may be added together. This is known as a 

synergistic effect, and is be more effective than the individual factors alone. In 

a dried fermented meat product, the growth of microorganisms varies with 

storage temperature, water activity, pH, presence of additives (e.g., salt, nitrite) 

and lack of oxygen. 

Some examples: 

• When the water activity is lower, the pH range at which an organism can 

grow is more limited. 

• When the pH is lower, the water activity that limits growth will be higher. 

• The presence of preservatives can affect the pH at which an organism 

grows. 

• Growth may take longer at lower temperatures when preservatives are 

present. 

The following are some common factors. 

• product time/temperature profile 

• water activity (aw) When other environmental conditions are optimal, most 

microorganisms do not exhibit growth below 0.91 water activity, with a few 

relevant exceptions, notably the staphylococci and fungi. Staphylococcus 

aureus, a common meat pathogen, can grow as low as 0.86 aw depending 

upon the other growth conditions, particularly if oxygen is present. 

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• pH and/or titratable acidity (% acid) 

• relative humidity 

• ingoing sodium nitrite concentration 

• % salt/brine concentration 

• Chemicals (often called preservatives, antimicrobial compounds, or 

antimicrobials) may be added to foods to inhibit microbial growth or to kill 

microorganisms. Most chemicals cause inhibition rather than inactivation. 

Acids and their salts (e.g., lactic acid, sodium lactate), nitrites, some 

phosphates, and sodium chloride (salt) are common chemicals added to 

meat and poultry. Sodium nitrite is the active curing ingredient for typical 

meat curing. This chemical also helps provide microbial stability, and acts 

as a potent antioxidant. Salt (sodium chloride) is another ingredient, often 

used in the manufacture of dried meat products. Salt exhibits many 

functions including suppressing microbial growth and reducing water 

activity. Chemical acidulants are specific acids that are added to some 

dried meat product formulations to lower pH. Many establishments are 

now adding sodium lactate/diacetate or other organic salts as an 

antimicrobial agent to their RTE meat or poultry products in order to meet 

the Listeria requirements. Lactate and diacetate can inhibit the growth of 

C. perfringens during cooling. 

Multiple Hurdle – Lethality 

Most RTE products that rely on multiple hurdles for lethality are not 

specifically addressed with a regulatory performance standard. As 

explained earlier, establishments must consider the food safety hazards that are 

reasonably likely to occur in these processes and establish steps to prevent, 

eliminate or reduce those hazards to an acceptable level, per 9 CFR 417.2. FSIS 

expects establishments to include the lethality pathogen reduction targets, and 

stabilization log outgrowth controls for C. perfringens and C. botulinum, in its 

HACCP plan or supporting documentation. FSIS recommends that the lethality 

treatment of shelf-stable meat products achieve at least a 5.0-log10 reduction of 

Salmonella spp. and at least a 5.0-log10 reduction for shiga toxin-producing 

Escherichia coli (E. coli) (STEC) for products containing beef. The lethality 

treatment of shelf-stable poultry products should also achieve at least a 5.0-log10 

reduction of Salmonella spp. Although poultry jerky is considered to fall under the 

performance standard in 9 CFR 381.150 (i.e., a 7.0-log10 reduction of Salmonella 

spp.), the regulation allows for the use of an alternative lethality that achieves an 

equivalent probability that no viable Salmonella organisms remain in the finished 

product. Research has supported that a 5.0-log10 reduction in in Salmonella is 

sufficient for such shelf-stable products. For most shelf-stable products, the pH 

(≤ 4.6) or water activity (0.93) preclude the growth of the primary hazards of

concern (i.e., Clostridium perfringens and Clostridium botulinum. 

For lethality treatments, however, it is not sufficient for establishments to 

demonstrate certain factors such as low water activity or pH are met to prohibit 

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the growth of biological hazards like Salmonella. As previously explained, the 

establishment should identify and support the lethality pathogen reduction targets 

(e.g., 5-log reduction of Salmonella) its multiple hurdles will achieve., 

Multiple Hurdles Example: Lebanon bologna is a semi-dry sausage, and this 

process is a typical example of the multiple hurdles concept. The multiple 

hurdles for Lebanon bologna are fermentation and low temperature heating. 

There are several critical operational parameters that affect the efficacy of these 

hurdles. In order for a process that relies on fermentation and low temperature 

heating as lethality steps to demonstrate food safety – these parameters (at the 

levels found in the scientific support) should be followed: 

Fermentation temperature/heating come up time, and hold time and 

temperature for a low temperature heat step – The temperature that the product 

is heated to, and the amount of time the product is held at this temperature, are 

critical to ensuring that adequate lethality is achieved. 

1. Differences in equipment (e.g., smokehouses and ovens) used in the 

processing of Lebanon bologna can influence the effectiveness of the 

process and, in particular, the speed of fermentation or acidification and 

heating. 

2. Relative humidity is an important parameter in all dried meat processes. 

A relatively high humidity is preferred to keep the product surface moist 

during the fermentation and intermediate heating steps, prior to drying. 

Controlling humidity prevents premature and uneven drying at the surface 

and also shortens the time it takes for the product core to reach the 

desired temperature. 

3. pH and time to reach target pH – Semi-dry sausage products like 

Lebanon bologna are usually fermented to a pH of between 4.4 - 4.6. The 

establishment should be fermenting its product to the pH that is 

recommended in the support documents. In addition to the pH level itself, 

the time it takes the product to reach the desired pH is also important. If a 

product takes too long to reach the desired pH, the acid resistance and 

pathogenicity of E. coli O157:H7 and Salmonella may increase. In 

addition, these conditions may favor Staphylococcus aureus growth and 

enterotoxin production. 

4. The starter culture used in the product should be similar in composition 

to that used in the support, to ensure that fermentation is achieved, and 

the rate of pH drop is as expected. 

5. Product Characteristics – 

a. Casing diameter - Product casing size and shape are critical 

operational parameters in fermented, semi-dry processes because 

they affect heat transfer. It is important that the diameter of the 

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product used in the establishment’s process is the same or smaller 

than that of the product used in the supporting documentation. If 

the diameter of the establishment’s product is larger, it is possible 

that the product core will take longer to reach the desired 

temperature and pH, and a lower level of pathogen reduction would 

be achieved. 

b. Product formulation – Product formulation plays a role in the 

fermentation process and in the heat transfer during the 

intermediate heating step. Product formulation also may affect 

microbial resistance to acid or heat. The establishment should have 

an understanding of the critical operational parameters associated 

with the product formulation (e.g., % salt, moisture level, nitrite or 

any other preservatives, and % fat) and should ensure that the 

material used in the supporting documentation is similar to their 

product with respect to those critical operational parameters. 

c. Casing – The casing influences moisture exchange. Products with 

impermeable, semi-permeable, or permeable casings exchange 

moisture with the environment differently and can, therefore, 

influence the rate of product acidification, the penetration of heat 

into the interior of the product, and the maximum internal 

temperature reached by the product. 

Published Industry Processing Guidelines 

In 1994, a food borne illnesses outbreak occurred due to the consumption of 

fermented dry-cured salami contaminated with E. coli O157:H7. Up until this 

point in time, the industry and FSIS believed that the addition of cure and salt to 

the raw meat ingredients, competitive exclusion, the reduction in pH from the 

fermentation process, and the subsequent drying of sausage products would be 

sufficient to prevent, eliminate, or reduce E. coli O157:H7 to an acceptable level. 

Shortly after the outbreak, FSIS held a series of meetings with a number of 

associations representing the fermented sausage industry. The objective of the 

meetings was to share information regarding the outbreak of E. coli O157:H7 

illnesses attributed to the consumption of fermented sausage product and work 

cooperatively to develop preventive measures aimed at preventing future 

outbreaks. As a result of these meetings, industry representatives and FSIS 

agreed that manufacturers of dry and semi-dry fermented sausages would 

ensure that their processes destroyed E. coli O157:H7. 

In 1996, a group called the Blue Ribbon Task Force of the National Cattlemen’s 

Beef Association, consisting of scientists from FSIS, ARS, academia, and 

industry issued a report, “Dry Fermented Sausage and E. coli O157:H7,” that 

identified several options that would ensure a 5-log10 reduction E. coli 

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O157:H7 in dry and semi-dry fermented sausages. These processes involve 

various combinations of fermentation temperature, pH at the end of fermentation, 

holding times and temperatures based on the diameter of the casing, cooking or 

heating and drying. Many establishments continue to follow these 

recommendations and you may see this report used as supporting 

documentation. These options include: 

• Utilize a heating step as described in 9 CFR 318.17 or 318.23. 

Currently, heating after fermentation in accordance with FSIS compliance 

guidelines or FSIS regulations is the only procedure accepted without 

additional support for destroying E. coli O157:H7. 

• Apply a validated heat treatment of equal lethality, i.e., achieves a 5-log10 

reduction of E. coli O157:H7 only (does not apply to Salmonella). 

Including a mild heat treatment (a kill step) into the process (above 125°F for 

a sufficient duration) after fermentation is an effective means of assuring the 

destruction of E. coli. O157:H7. 

• Apply a validated minimum 5- log10 reduction or process that results in a 

level of E. coli O157:H7 in the final product below 1 cfu/100 gram. 

The establishment’s process may include a combination of antimicrobial 

interventions (such as competitive exclusion, pH, holding time and 

temperature, and drying) that collectively demonstrates a 5-log10 reduction of 

E. coli O157:H7 or that the level of E. coli O157:H7 in the finished product is 

below 1 cfu/100 gram of product. 

• Sample raw ingredients to demonstrate that there is less than one E. coli 

O157:H7 organism per 100g and apply a 2-log10 lethality treatment. 

Since fully cooking fermented sausages changes product characteristics such 

as flavor, distinction between lean and fat particles, and firmness, an 

establishment may prefer this option. 

GMPs for Fermented Dry and Semi-Dry Sausage Products 

Degree-hour Limit–Establishments that produce dry and semi-dry fermented 

sausages may use another industry processing guideline titled “Good 

Manufacturing Practices (GMP) for Fermented Dry and Semi-dry Sausage 

Products” developed by the American Meat Institute Foundation to support 

decisions in their HACCP plan. In addition to providing information on the 5 

options for controlling E. coli O157:H7, it establishes a GMP for time and 

temperature (degree-hour limit) control for fermentation and direct acidulation. 

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To control the growth of E. coli O157:H7 and the growth and enterotoxin 

production by Staphylococcus aureus, it is important to reach a pH of 5.3 or 

lower as fast as possible during fermentation or direct acidification. 

Staphylococci can begin to grow at a temperature of 60°F or above. Therefore, 

while obtaining the pH of 5.3 or less, it is important to limit the time at which the 

sausage is above 60°F. This is the concept of degree-hours – the number of 

hours at a temperature above 60°F multiplied by the number of degrees above 

that temperature. A process is acceptable if the product reaches pH 5.3 within a 

certain number of degree-hours. Processes attaining a temperature less than 

90°F before reaching pH 5.3 are limited to 1200 degree-hours. Processes 

reaching a temperature of 90°F-100°F prior to reaching pH 5.3 are limited to 

1000 degree-hours. Processes exceeding 100°F before reaching pH 5.3 are 

limited to 900 degree hours. 

NOTE: Meeting degree-limits does not ensure any specific log reduction in E. 

coli O157:H7. Therefore, establishments need additional support for the log 

reduction achieved by the fermentation if it is used as part of a multi-hurdle 

lethality treatment. 

Calculating the Degree Hour Limit Example: An establishment ferments a 

batch of pepperoni at a constant chamber temperature of 80°F for a total of 55 

hours which achieves a pH ≤ 5.3. The following table is derived from the GMP 

for Fermented Dry and Semi-dry Sausage Products guideline. 

Maximum 

Temperature 

Maximum Degree 

Hours 

< 90°F 1200 

90°F to 100°F 1000 

> 100°F 900 

Step 1: 80 (chamber temp.) – 60 (Staph growth limit) = 20 

Step 2: 20 x 55 (total hours) = 1100 degree hours 

Step 3: Meets the < 90°F / 1200 degree-hour limit (1100 hours is less than 

1200 hours) to achieve a pH ≤ 5.3 

GMPs for Fermented Dry and Semi-Dry Sausage Products Example: An 

establishment’s hazard analysis has identified the growth of pathogens such as 

Salmonella, E. coli O157:H7 and Staphylococcus aureus as biological hazards 

being likely to occur during fermentation, and therefore has identified the 

fermentation step as a CCP for its RTE pepperoni product. It has established the 

following critical limit at the fermentation step in its HACCP plan “a pH ≤ 5.3

achieved by using a fermentation chamber temperature and time that meet the 

degree-hour limit documented in the GMP guidelines”. The establishment 

maintains a copy of the Good Manufacturing Practices (GMP) for Fermented Dry 

and Semi-dry Sausage Products guidelines in its HACCP file. 

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Inspection Verification 

FSIS Directive 7111.1 contains detailed instructions for verifying lethality and 

stabilization processes. Inspection program personnel should use the Hazard 

Analysis Verification task to verify that establishments have: 

• Identified supporting documentation for their process (particularly the 

lethality and stabilization CCPs and critical limits), 

• Identified support that demonstrates the expected level of bacterial 

pathogen reduction, 

• Identified the critical operational parameters from the support that are 

relevant to the process, 

• Implemented the critical operational parameters into the process, either as 

a CCP or as a prerequisite program, and 

• Gathered data demonstrating the effectiveness of the implementation of 

the critical operational parameters (validation). 

Inspection program personnel should use the HACCP Verification task to verify 

that establishments are effectively implementing the CCPs and prerequisite 

programs, and are meeting the critical limits. 

Summary 

In this module we discussed the importance of cooking (lethality) and cooling 

(stabilization) CCPs and critical limits. We discussed the use of multiple hurdles 

in food safety systems, such as Lebanon bologna, that depend on a combination 

of parameters to ensure safety. We reviewed FSIS regulatory requirements that 

apply to lethality and stabilization, and reviewed the key compliance guidelines 

that you should be familiar with. We reviewed your inspection verification 

responsibility to ensure that establishments provide support for the design of their 

CCPs and critical limits, and that they implement all critical operational 

parameters. 

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Lethality, Stabilizationand Multiple HurdlesWorkshop 

Refer to the handout to complete the following questions. 

1. Define the following terms: 

a. Lethality 

b. Stabilization 

2. a. State the regulatory lethality performance standard for cooked beef, 

including the log reduction and the target organism. Include the regulation 

that covers this. 

b. What FSIS compliance guide do many establishments use to support 

design of lethality processes? 

3. a. State the regulatory stabilization performance standard for cooked poultry, 

including the log growth requirements and the target organisms. Include the 

regulation that covers this. 

b. What FSIS compliance guide do many establishments use to support 

design of stabilization processes? 

4. Why must high relative humidity be applied during the first part of the heating 

process (lethality treatment) for jerky products, and certain fully cooked RTE 

meat and poultry products? 

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5. In each scenario below, determine whether the establishment can use the 

FSIS lethality compliance guideline (Appendix A) to support its critical limits 

for meeting the lethality performance standard. 

a. The establishment cooks cured beef briskets in a sealed, moisture 

impermeable bag to an internal temperature of 145°F for 4 minutes. 

b. The establishment cooks oven roasted turkey breast to an internal 

temperature of 150°F for 72 seconds in an oven that has steam 

continuously injected for 50% of the cooking time but not less than 1 hour. 

c. The establishment roasts beef rounds to an internal temperature of 158°F 

in a smokehouse that is sealed for 50% of the cooking time but not less 

than 1 hour. 

d. The establishment smokes RTE boneless hams of about 8 lbs. in a 

smokehouse to an internal temperature of 171°F. 

6. An establishment produces cooked corned beef products, a cured product 

formulated with at least 100 ppm sodium nitrite. It has the following critical 

limits listed in the HACCP plan at the chilling CCP: cool the product’s internal 

temperature from 130°F to 80°F in 4 hours and from 80°F to 45°F in 14 hours. 

Can the establishment use FSIS stabilization compliance guideline (Appendix 

B) option 3 to support its critical limits? Why or why not? 

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Resources 

American Meat Institute Foundation. 1997. Good Manufacturing Practices for 

Fermented Dry and Semi-Dry Sausage Products. (The Degree-Hour Concept) 

http://www.aamp.com/documents/AMIF_degreehours.pdf 

Dry Fermented Sausage and E. coli O157:H7, Blue Ribbon Task Force, National 

Cattlemen’s Association (The Five Options) 

http://www.beefissuesquarterly.com/CMDocs/BeefResearch/Safety_Meeting_Exec_Su 

mmaries/1996_dry_fermented_sausage.pdf 

ICMSF (International Commission on Microbiological Specifications for Foods). 

1996. Microorganisms in Foods 5. Characteristics of Microbial Pathogens. 

Blackie Academic & Professional, London. 

Appendix A - Lethality Compliance Guideline - FSIS Salmonella Compliance 

Guidelines for Small and Very Small Meat and Poultry Establishments that 

Produce Ready-to-Eat (RTE) Products and Revised Appendix A 

https://www.fsis.usda.gov/wps/wcm/connect/bf3f01a1-a0b7-4902-a2dfa87c73d1b633/Salmonella-Compliance-Guideline-SVSP-RTE-AppendixA.pdf?MOD=AJPERES 

Appendix B - Stabilization Compliance Guideline - FSIS Compliance Guideline 

for Stabilization (Cooling and Hot-Holding) of Fully and Partially Heat-Treated 

RTE and NRTE Meat and Poultry Products Produced by Small and Very Small 

Establishments and Revised Appendix B 

https://www.fsis.usda.gov/wps/wcm/connect/9ac49aba-46bc-443c-856b59a3f51b924f/Compliance-Guideline-Stabilization-Appendix-B.pdf?MOD=AJPERES 

Jerky Compliance Guidelines and Information 

https://www.fsis.usda.gov/wps/wcm/connect/5fd4a01d-a381-4134-8b91-

99617e56a90a/Compliance-Guideline-Jerky-2014.pdf?MOD=AJPERES 

Lebanon Bologna Compliance Guideline 

http://www.fsis.usda.gov/wps/wcm/connect/d5be2be1-3c57-45f6-af53-

e71393eaaeb6/Compliance_Guideline_Lebanon_Bologna.pdf?MOD=AJPERES 

Salmonella Compliance Guidelines for Small and Very Small Meat and Poultry 

Establishments that Produce Ready-to-Eat (RTE) Products 

http://www.fsis.usda.gov/wps/wcm/connect/8dd0f238-08d7-4ca0-a31a77fa3ca8acf6/C-17_New_Technology_FY2004_Final_Report.pdf?MOD=AJPERES 

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Performance Standards for the Production of Certain Meat and Poultry Products 

Docket No. 95-033F 

http://www.fsis.usda.gov/OPPDE/rdad/FRPubs/95-033F.pdf 

Pathogen Modeling Programs 

USDA ARS Pathogen Modeling Program Online: 

https://pmp.errc.ars.usda.gov/PMPOnline.aspx 

USDA ARS Pathogen Modeling Program Version 7.0 and 6.1 versions: 

https://www.ars.usda.gov/northeast-area/wyndmoor-pa/eastern-regional-researchcenter/residue-chemistry-and-predictive-microbiology-research/docs/pathogenmodeling-program/pathogen-modeling-program-models/ 

UK IFR ComBase Perfringens Predictor Model: 

http://www.ifr.ac.uk/safety/growthpredictor/ 

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Regulations 

Sec. 417.2(c)(3) Critical limits shall, at a minimum, be designed to ensure that applicable targets 

or performance standards established by FSIS, and any other requirement set forth in this chapter 

pertaining to the specific process or product, are met. 

Sec. 417.5(a)(1) and (2) Supporting Documentation -(a) The establishment shall maintain 

the following records documenting the establishment's HACCP plan: 

(1) The written hazard analysis prescribed in Sec. 417.2(a) of this part, including all supporting 

documentation; 

(2) The written HACCP plan, including decision-making documents associated with the selection 

and development of CCPs and critical limits, and documents supporting both the monitoring and 

verification procedures selected and the frequency of those procedures. 

Sec. 318.17 Requirements for the production of cooked beef, roast beef, and cooked 

corned beefproducts. 

(a) Cooked beef, roast beef, and cooked corned beef products must be produced using 

processes ensuring that the products meet the following performance standards: 

(1) Lethality. A 6.5-log10 reduction of Salmonella or an alternative lethality that achieves an 

equivalent probability that no viable Salmonella organisms remain in the finished product, as we l 

as the reduction of other pathogens and their toxins or toxic metabolites necessary to prevent 

adulteration, must be demonstrated to be achieved throughout the product. The lethality process 

must include a cooking step. Controlled intermediate step(s) applied to raw product may form 

part of the basis for the equivalency. 

(2) Stabilization. There can be no multiplication of toxigenic microorganisms such as 

Clostridium botulinum, and no more than 1-log10 multiplication of Clostridium perfringens within 

the product. 

Sec. 318.23 Heat-processing and stabilization requirements for uncured meat 

patties.

(a) Definitions. For purposes of this section, the following definitions shall apply: 

(1) Patty. A shaped and formed, comminuted, flattened cake of meat food product. 

(2) Comminuted. A processing term describing the reduction in size of pieces of meat, 

including chopping, flaking, grinding, or mincing, but not including chunking or sectioning. 

(3) Partially-cooked patties. Meat patties that have been heat processed for less time or using 

lower internal temperatures than are prescribed by paragraph (b)(1) of this section. 

(4) Char-marked patties. Meat patties that have been marked by a heat source and that have 

been heat processed for less time or using lower internal temperatures than are prescribed by 

paragraph (b)(1) of this section. 

(b) Heat-processing procedures for fully-cooked patties. (1) Official establishments which 

manufacture fully-cooked patties shall use one of the following heat-processing procedures: 

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Permitted Heat-Processing Temperature/Time Combinations for Fully-Cooked Patties 

Minimum internal temperature Minimum holding time 

at the center of each patty after required internal 

(Degrees) temperature is reached 

(Time) 

Fahrenheit Or centigrade Minutes Or seconds 

151............................ 66.1............. .68 41 

152............................ 66.7............. .54 32 

153............................ 67.2............. .43 26 

154............................ 67.8............. .34 20 

155............................ 68.3............. .27 16 

156............................ 68.9............. .22 13 

157 (and up)............... 69.4 (and up) .17 10 

(2) The official establishment shall measure the holding time and temperature of at least one 

fully-cooked patty from each production line each hour of production to assure control of the heat 

process. The temperature measuring device shall be accurate within 1 degree F. 

(3) Requirements for handling heating deviations. (i) If for any reason a heating deviation has 

occurred, the official establishment shall investigate and identify the cause; take steps to assure 

that the deviation will not recur; and place on file in the official establishment, available to any 

duly authorized FSIS program employee, a report of the investigation, the cause of the deviation, 

and the steps taken to prevent recurrence. 

(ii) In addition, in the case of a heating deviation, the official establishment may reprocess the 

affected product, using one of the methods in paragraph (b)(1) in this section; use the affected 

product as an ingredient in another product processed to one of the temperature and time 

combinations in paragraph (b)(1) in this section, provided this does not violate the final product's 

standard of composition, upset the order of predominance of ingredients, or perceptibly affect the 

normal product characteristics; or relabel the affected product as a partially-cooked patty product, 

if it meets the stabilization requirements in paragraph (c) of this section. 

(c) Stabilization. (1) Fully cooked, partially cooked, and char-marked meat patties must be 

produced using processes ensuring no multiplication of toxigenic microorganisms such as 

Clostridium botulinum, and no more than a 1 log10 multiplication of Clostridium perfringens, 

within the product. 

(2) For each meat patty product produced using a stabilization process other than one 

conducted in accordance with the Hazard Analysis and Critical Control Point (HACCP) system 

requirements in part 417 of this chapter, an establishment must develop and have on file, 

available to FSIS, a process schedule, as defined in Sec. 301.2 of this chapter. Each process 

schedule must be approved in writing by a process authority forsafety and efficacy in meeting the 

performance standards established for the product in question. A process authority must have 

access to an establishment in order to evaluate and approve the safety and efficacy of each 

process schedule. 

(3) Under the auspices of a processing authority, an establishment must validate new or altered 

process schedules by scientifically supportable means, such as information gleaned from the 

literature or by challenge studies conducted outside the plant. 

(4) Partially cooked patties must bear the labeling statement ``Partially cooked: For Safety 

Cook Until Well Done (Internal Meat Temperature 160 degrees F.).'' The labeling statement must 

be adjacent to the product name, and prominently placed with such conspicuousness(as 

compared with other words, statements, designs or devices in the labeling) as to render it likely to 

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Lethality, Stabilization and Multiple Hurdles 

10/27/2021 

be read and understood by the ordinary individual under customary conditions of purchase and 

use. 

(5) Char-marked patties must bear the labeling statement ``Uncooked, Char-marked: For 

Safety, Cook Until Well Done (Internal Meat Temperature 160 degrees F.).'' The labeling 

statement shall be adjacent to the product name, at least one-half the size of the largest letter in 

the product name, and prominently placed with such conspicuousness (as compared with other 

words, statements, designs or devices in the labeling) as to render it likely to be read and 

understood by the ordinary individual under customary conditions of purchase and use. 

Sec. 381.150 Requirements for the production of fully cooked poultry products and 

partially cooked poultry breakfast strips. 

(a) Fully cooked poultry products must be produced using processes ensuring that the products 

meet the following performance standards: 

(1) Lethality. A 7-log10 reduction of Salmonella or an alternative lethality that achieves an 

equivalent probability that no viable Salmonella organisms remain in the finished product, as we l 

as the reduction of other pathogens and their toxins or toxic metabolites necessary to prevent 

adulteration, must be demonstrated to be achieved throughout the product. The lethality process 

must include a cooking step. Controlled intermediate step(s) applied to raw product may form 

part of the basis for the equivalency. 

(2) Stabilization. There can be no multiplication of toxigenic microorganisms such as 

Clostridium botulinum, and no more than a 1 log10 multiplication of Clostridium perfringens 

within the product. 

(b) Partially cooked poultry breakfast strips must be produced using processes ensuring that the 

products meet the performance standard listed in paragraph (a)(2) of this section. Labeling for 

these products must comply with Sec. 381.125. In addition, the statement ``Partially Cooked: For 

Safety, Cook Until Well Done'' must appear on the principal display panel in letters no smaller 

than \1/2\ the size of the largest letter in the product name. Detailed cooking instructions shall be 

provided on the immediate container of the products. 

(c) For each product produced using a process other than one conducted in accordance with the 

Hazard Analysis and Critical Control Point (HACCP) system requirements in part 417 of this 

chapter, an establishment must develop and have on file, available to FSIS, a process schedule, as 

defined in Sec. 381.1 

(b). Each process schedule must be approved in writing by a process authority for safety and 

efficacy in meeting the performance standards established for the product in question. A process 

authority must have access to an establishment in order to evaluate and approve the safety and 

efficacy of each process schedule. 

(d) Under the auspices of a processing authority, an establishment must validate new or altered 

process schedules by scientifically supportable means, such as information gleaned from the 

literature or by challenge studies conducted outside the plant. 

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