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Q. H. ZHANG, Food Science and Technology, Ohio State University, 2121 Fyffe Road, Columbus, OH 43210, D. W. SCHAFFNER, Department of Food Science, Cook College, Rutgers, The State University of New Jersey, 65 Dudley Road, New Brunswick, NJ 08901-8520, M. D. Pierson, Department of Food Science and Technology, Virginia Polytechnic Institute and State University, Food Science Building, Blacksburg, VA 24061, and G. Barbosa-Canovas, Department of Biological Systems Engineering, Washington State University, 207 L. J. Smith Hall, Pullman, WA 99164.

Pulsed light for food preservation involves the use of intense and short duration pulses of broad spectrum white light. Processes developed to sterilize or reduce the microbial population on the surface of packaging materials will be presented. Due to opaque and irregular surfaces of foods, lower inactivation levels are attained; however, shelf-life can be significantly extended and risk of pathogenic microorganisms can be reduced. Oscillating magnetic fields (OMF) to inactivate microorganisms has the potential to pasteurize foods while improving quality and shelf-life. Preservation of foods with OMF involves sealing food in a plastic bag and subjecting it to 1 to100 pulses in an OMF with a frequency between 5 to500 kHz for of 25 ms to 100 ms in a magnetic field intensity of 5 to 50 Tesla. Magnetic fields may cause both stimulation or inhibition in the growth and reproduction of microorganisms. Present status of high intensity X-ray pulses to kill surface and subsurface bacteria will be presented. Recommendations will be made as how to relate kinetics of microbial inactivation to dosage descriptors using pulsed light, OMF and pulsed X-ray. Recommendations will also be made in areas where additional research and development are needed.