<UL> <LI>Determine kinetics and mechanisms of inactivation of pathogens and their surrogates by PEF and RFEF technologies; <LI> Develop, evaluate and validate PEF and RFEF alone and in combination with other processes to ensure safety and security of fresh apple cider and fresh orange juice; <LI>Develop advanced thermal and nonthermal processes and combinational processes to ensure the safety and security of liquid egg products; <LI> Evaluate quality, shelf life and cost of products processed by PEF, RFEF and combinational processes, and packaged aseptically or with antimicrobial agents, in comparison to thermal pasteurization.
Approach: Nonthermal, advanced thermal and hurdle technologies will be developed to inactivate bacteria pathogens. Design, modify and develop PEF, RFEF and UV processes focusing on products with high viscosity and/or high protein content, such as liquid egg, fruit and vegetable juices, and fermented beverages. Validate these technologies relative to microbial inactivation for commercially practical reduction of pathogens in representative foods. Target organisms will include E. coli O157:H7, Salmonella, Listeria monocytogenes, and Lactobacillus plantarum. Selected pilot plant scale equipment will be validated using pathogen-inoculation products in the ERRC BSL-2 Containment Chamber facility. Process and cost simulation models will be developed to evaluate the feasibility of each or combined processing technologies. Mechanisms and kinetics of microbial inactivation focusing on bacterial membrane damage and the basis of synergistic treatment interactions will be determined. Antagonistic relationships between human pathogens, nutrient composition and the indigenous microflora along with the effects of processing and packaging technologies and storage conditions on physical, sensory, nutritional, and microbiological properties will be dwetermined in studies of liquid foods. Chemical changes and accumulation of undesirable substances including aroma and off-flavor compounds will be linked to freshness properties of processed foods.