Improvement of Thermal and Alternative Processes for Foods

Non-Technical Summary: The research proposed is diverse with respect to processes and commodities because of the complex nature of foods and processing technologies. This requires characterization of relevant physical-chemical properties of the food under investigation. Processes and process models must be adapted accordingly. Methods of measuring engineering properties are evolving and must be standardized. Biosensing techniques are becoming increasingly important and should be pursued. Process technology and consumer preferences continually evolve and present new opportunities to produce products with improved nutritional and sensory characteristics at a price that consumers will pay. Changes in economic, social, and demographic conditions have created an increased desire for new food products with higher sensory quality, new packaging, more convenience, new delivery systems, and safer and more nutritious foods. These have resulted in a number of alternative thermal and non-thermal preservation technologies. New and exciting trends in science, including molecular biology, nanotechnology, and nutragenomics, are changing the way in which engineers and scientists address issues such as process efficiency, product safety and quality. As demands for new food products containing nutraceuticals and/or new functionality increase, reliable means to characterize the effectiveness of these ingredients, as well as their interactions with other ingredients, are urgently needed. Optical and biosensing techniques for real-time evaluation of food system during processing and storage should be investigated. <P> Approach: The effects of food composition and microstructural elements on electrical properties of foods will be investigated to better control ohmic heating and pulsed electric field technologies. The effects of media conductivity on microbial inactivation of gram-positive and gram-negative bacteria using pulsed electric field pasteurization will be determined. Computer vision and visible/near-infrared (NIR) spectroscopy will be used to predict food color and other quality factors at NE. A hyperspectral imaging system to predict beef tenderness and a NIR spectroscopic technique to detect yolk contamination in egg white will be developed. The chemical kinetics of extrusion will be studied to assess chemical and toxicological changes in fumonisin FB1 during extrusion cooking of contaminated corn grits. The microbial destruction in non-thermal processes will be studied to develop predictive models to describe the growth of pathogens in food systems. Models will be developed to address the general behavior of biopolymers subjected to the mechanical, thermal, and chemical processes inherent in the extrusion process; and the interaction of the biopolymers with the size, configuration, and type of extruder with the intent of generalizing the models. The contributing CA, MI, MO, NE, NJ and SD stations will re-establish an ad hoc committee on extrusion and develop a single (combined) report on modeling.