Based on the results of a recent Clostridium perfringens Market Basket Study, the U.S. Department of Agriculture's Food Safety and Inspection Service (USDA’s FSIS) has concluded that the guidance currently being used for the cooling of large-mass, non-intact ready-to-eat (RTE) meat and poultry products is adequate and does not merit revision.

FSIS commissioned the Market Basket Study through Federal Emergency Response Network (FERN) laboratories in response to comments on the 2017 Stabilization Guideline for Meat and Poultry Products (Revised Appendix B) indicating that large-mass non-intact products could not be cooled quickly enough to meet recommended cooling options. For example, cooling from 120 °F to 80 °F in less than 1.5 hours or from 130 °F to 80 °F in less than 1.5 hours during the first stage of cooling. Such cooling options were designed to meet FSIS’ regulatory performance standards of no more than 1 log₁₀ outgrowth of C. perfringens in meat and poultry products during cooling, which were developed using baseline data and are supported with newer data demonstrating that 3-4 log₁₀ level of C. perfringens could occur in raw products. Subsequently, a 2 log₁₀ safety margin was added, which is the level at which C. perfringens spores could germinate and grow greater than 1 log₁₀ and approach illness-causing levels of contamination.

The Market Basket Study was commissioned to address a scientific gap identified in the processing of large-mass, non-intact RTE products in the 2021 Revised Appendix B, which allows establishments to cool the products using the recommendations from the 1999 guideline; specifically, cooling from 120 °F to 55 °F in less than 6 hours without monitoring the time during the first stage of cooling between 120 °F to 80 °F. The study aimed to determine the potential risk from large-mass, non-intact RTE products if establishments continue to follow the cooling parameters from the 1999 version of the guideline that are included in the 2021 Revised Appendix B.

For the study, RTE beef, poultry, and pork shoulder samples were purchased between May and September 2021 from retail locations in eight states (California, Colorado, Iowa, Michigan, Minnesota, Missouri, Ohio, and Virginia). Analysis by FERN laboratories revealed that only one beef sample was positive for C. perfringens at 1.08 log₁₀ colony forming units per gram (cfu/g), and all other samples were below the limit of detection (0.5 log₁₀ cfu/g).

The results suggest that the presence and outgrowth of C. perfringens in large-mass, non-intact RTE meat and poultry products produced under FSIS inspection is controlled using the less stringent cooling parameters from the 1999 guideline included in the scientific gap. Therefore, FSIS does not intend to make changes to the regulatory performance standards under the 2021 Revised Appendix B, and establishments may continue to use the less stringent cooling procedures identified for these products.