Engineering for Food Safety and Quality

Non-Technical Summary: With an increasing demand by consumers for fresh-like, healthy, nutritious and safe food, the US food processing industry is continually challenged. Furthermore, emerging pathogenic microorganisms, tolerant to conventional treatment methods, create a demand for improved and novel food processes. The industry must constantly redefine technology to assure wholesomeness in processed foods. Thus, new and existing technologies must meet the challenge and play a pivotal role in improving the quality of value-added food products. Without extensive research, it would be difficult for the industry to meet these demands. To effectively compete in the global markets, the US food industry requires ready access to the scientific knowledge, well prepared personnel with appropriate skills, and a continuous dialog between academic researchers and industry practitioners. Collaborations among engineers, food scientists and other experts across the nation can effectively address these needs of the industry by advancing technologies through research, preparing our future work force through educating the students, and bridging the gap between research and implementation through outreach. The stakeholders impacted by this project will include the food industry, federal regulatory agencies, and consumers. The mission of this multistate project is to advance technologies for the purpose of improving food safety, quality and security. This will be accomplished by virtue of collaboration and synergy among participating experiment stations and disciplines. The research outcomes of this project will be used to enhance education and outreach programs for stakeholders. <P> Approach: Obj 1. Advancing the fundamental science and application of technologies to ensure safety and improve quality of food products Obj. 1a. Utilize innovative methods to characterize food materials We have developed a visible/near-infrared (400-1000 nm) and a near-infrared (900-1700 nm) hyperspectral imaging systems. These hyperspectral imaging systems, along with other imaging and spectroscopy systems, will be used to characterize various food products. Our current focus is on optimizing hyperspectral image analysis methods for beef tenderness prediction and detection of freeze injury in cucumbers. Hyperspectral and magnetic resonance images of normal and freeze-damaged cucumbers will be acquired. In addition, texture profile analysis (TPA) of the cucumber samples will be conducted using a texture analyzer (Stable Microsystems, UK; model: TA-XT plus). MRI experiments will be conducted using a 9.4 T (400 MHz for protons), 89 mm vertical bore MR system (Varian, inc. Walnut Creek, CA) equipped with triple axis gradients (100 G/cm) and a 4 cm millipede transmit/receive radiofrequency coil. T1 and T2 relaxation times of the samples will be assessed using a multi-echo multi-slice (MEMS) sequence. 1b. Develop new and improved processing technologies We have developed various improved food processing technologies including pulsed electric field (PEF) processing, high pressure processing, and ultraviolet radiation. We will continue to evaluate PEF processing for extracting bioactive compounds from food and agricultural waste products. Our current focus is on extracting bioactive compounds from grape pomace and cabbage. When plant cells are subjected to high voltage pulses, the cell walls break and extraction yield of bioactive compounds is increased. Bioactivity of the compounds extracted compounds will be evaluated using cancer and normal cell cultures, in collaboration with Colorado State University. 1c. Develop mathematical models to enhance understanding of, and, optimize food processes Our current focus is on developing a mathematical model to enhance our understanding of microwave processing. The overall goal is to integrate heat transfer and thermal destruction models in a risk assessment model to assess the risks of microwave cooking with a goal of improving the uniformity of heating of a prepared, but not-ready-to-eat (NRTE) food in a domestic microwave oven. Obj 3. Develop outreach programs to disseminate best practices for enhancing food safety and quality to stakeholders We will continue to disseminate our predictive models on a website hosted at the University of Nebraska. We will conduct extensive outreach activities on our research on microwave modeling.