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<p>This mechanistic study will investigate how the structural and barrier properties of multilayer polymeric films are affected by both pressure and temperature. The study will inform the development of new materials for emerging technologies as well as conventional thermal processes. The overall goal of this research is to develop high oxygen barrier polymeric films for microwave, high hydrostatic pressure, and retort technologies. </p><p>Specific objectives are to:</p><p><ol><li>Design and fabricate new multilayer EVOH and coated-PET films with different microlayer thicknesses and additives, and evaluate the properties of these new materials after microwave, high-pressure and retort processing.</li><li>Develop kinetic models of food quality deterioration based on the oxygen and water vapor transmission rates of multilayer film, storage temperature, light exposure and initial food conditions. </li><li>Develop shelf-life prediction models and determine baseline oxygen and water vapor barrier properties of multilayer film-based pouches for three food categories to achieve desired shelf-lives. </li></ol></p>
Microwave-assisted thermal sterilization (MATS) and high pressure processes (HPP) offer great potential for the development of high-quality foods. However, in order for these technologies to reach their full commercial potential, they require polymeric packaging with a high oxygen and water vapor barrier. Thermal and pressure processes cause structural changes in polymers and increase their oxygen and water vapor transmission rates (OTR and WVTR), degrading the quality of processed foods during long-term storage and reducing their shelf-life to one year. This research aims to develop ethylene vinyl alcohol (EVOH) and coated polyethylene terephlate (PET)-based new polymeric structures by exploring how MATS and HPP processes affect the structural and barrier properties of polymeric films. The study will also examine how OTR and WVTR of packaging films, light exposure and initial food conditions affect the shelf-life of processed foods. This research will accomplish three main goals:1. Design and fabricate new multilayer EVOH and coated-PET films with different microlayer thicknesses and additives, and evaluate the properties of these new materials after microwave, high-pressure and retort processing2. Develop kinetic models of food quality deterioration based on the oxygen and water vapor transmission rates of multilayer film, storage temperature, light exposure and initial food conditions, and3. Develop shelf-life prediction models and determine baseline oxygen and water vapor barrier properties of multilayer film-based pouches for three food categories to achieve desired shelf-lives. This research will benefit the polymer industry, food companies, military, NASA and consumers by improving the quality and shelf-life of packaged foods. Findings will allow food companies to select appropriate packaging for specific foods processed using MATS, HPP and retort.