Existing models for pathogen inactivation, based on limited-scope laboratory tests, are insufficient to predict results in commercial convection cooking environments. Preliminary results suggest that differences in process humidity are a primary cause for this insufficiency. Consequently, the long-term goal of the proposed research is to develop improved methods for design and operation of thermal processes, based on the critical control criterion of pathogen inactivation.
Major growth in the market for fully-cooked meat products and recent changes in federal regulations have resulted in a significant need to validate process lethality in commercial cooking systems. Regulations state that processors must validate new or altered process schedules by scientifically supportable means.
The specific objectives are: <OL> <LI> To develop a quantitative, population-based model for thermal inactivation of a Salmonella "cocktail" in ground poultry breast meat subjected to air convection treatments. <LI> To formulate novel secondary models that relate the thermal inactivation parameters to humidity. <LI> To test the effect of heating rate on the validity of the inactivation model.<LI> To validate the inactivation models with pilot-scale data. </OL> Very small samples of ground meat will be inoculated with the target organisms and heated in a unique laboratory moist air heating system. Pathogen inactivation models will be developed from the resulting data. The predictive ability of these models will then be tested by comparing them to transient data from inoculated heating tests in a pilot-scale convection/ steam oven. The resulting models will ultimately help optimize process design and operation to ensure product safety.