Mechanism of Pathogen Survival During Microwave Thermalization (1999-02764)

Contamination of foods with microorganisms does occur, and cooking by the consumer is one of the last steps in food preparation that will kill microorganisms. Consumers, especially in high-risk groups, increasingly rely on microwave heating to cook or re-heat ready-to-eat foods. It has been reported that microorganisms are more likely to survive in foods cooked using microwaves than foods cooked using conventional methods. This increases the concern for the food safety of microwave cooked foods. Therefore, heating procedures using microwaves that assure product safety should be identified. Recent foodborne disease outbreaks with fresh produce have highlighted the fact that very little research has been conducted on the effectiveness of microwave heating on vegetable products or products that have fresh vegetables as a component. This project will determine the mechanism of microorganism survival during microwave heating; determine the role of fat in the food product on inactivation of the microorganisms; study the effect of the presence or absence of steam on inactivation of the microorganisms; and develop mathematical models to describe the cooking process in the microwave oven in the presence or absence of steam. Specific products to be tested include ground beef at different fat levels; chicken breasts with and without skin; broccoli; and a ready-to-eat meal-containing broccoli. This research will result in procedures that can be used to develop microwave-heating procedures that will increase food safety.