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G. V. BARBOSA-CáNOVAS, Biological Systems Engineering, Washington State University, Washington State University, Pullman, WA, 99164-6120 and B. G. Swanson, Wahington Sate University.

The search for nutritionally sound and minimally processed foods has significantly increased during the last few years. Consumers are looking into foods with fresh-like quality and little heat-induced degradation of nutritional and sensory properties. For this reason there is a keen interest in the development of nonthermal processes for the preservation of food. These include utilization of electric fields or magnetic fields (MF), ionizing radiation, light pulses, high hydrostatic pressure, bacteriocins, and antimicrobial enzymes. The primary advantages of MF as a potential tool in the inactivation of microorganisms have been cited as (1) minimal thermal denaturation of nutritional and sensory properties, (2) reduced energy requirement for adequate processing, and (3) potential treatment of foods inside a flexible-film package. However, from a realistic standpoint, the latter two benefits are still far from reach since contradictory results have been obtained and an extensive part of the field remains to be explored. It is the purpose of this presentation to review some of the proposed interaction mechanisms as well as some of the results that have been obtained by exposing living systems to different varieties of MF (e.g., low-frequency low-intensity fields and high-frequency high-intensity fields).