Purpose: To describe the new RTE product classification system developed for PHIS.
Methods: Before PHIS, RTE product classification basically came from two sources: A process-based classification system used by the testing labs, and information from FSIS Form 10,240-1. The new PHIS classification consisted of a combination of HACCP categories and an expert elicitation, supplemented by analysis of historical RTE data.
Results: The initial RTE product classification established 4 basic categories: Acidified/fermented, dried, salt-cured and fully cooked. Analysis of the product types within the ‘fully cooked’ category resulted in a further classification of that category into 7 product groups: 1) Hotdog, 2) sausage, 3) salad/spread/pate, 4) meat/non-meat multicomponent, 5) patty/nugget, 6) diced/shredded and 7) other. These product groups incorporated elements of both the prior process-based and 10,240-1-based systems. It was recognized that not all products conveniently fit a particular category or group. Accordingly, a flowchart was developed to select the single best product category/product group in which a given product might be classified based on the overall microbial lethality, preservation and production methods, while being aware that mixed, multiple production methods can occur. Subsequent to integration into PHIS, descriptions of the new classification system are being included in updated Directives and Listeria Compliance Guidelines.
Significance: Proper RTE product classification is essential for determining pathogen (Listeria and Salmonella) percent positive rates as a function of sample product type, thus yielding insights into the potential contamination risks associated with these products.