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

Pasteurization by pulsed electric fields (PEF) involves the application of pulses of high voltage to foods placed between electrodes, so that microbial inactivation is achieved through dielectric breakdown and electroporation of bacterial membranes.

Advantages of PEF over heat treatment include better quality of the food products and energy efficiency of the process. Currently, application of PEF pasteurization is restricted to food products that can withstand high electric fields (i.e., homogeneous liquids with low electrical conductivity) so that dielectric breakdown of foods is avoided. Another current limitation of the PEF process is the particle size of the foods, as geometry of the treatment chamber is partially determined by the size of particles.

Factors that affect the microbial inactivation with PEF can be classified into treatment conditions (electric field intensity, treatment time, temperature, and wave shape), microbial entity (type, concentration, and growth stage), and treatment media (pH, ionic strength, and conductivity). Examples of current and potential future applications in food preservation will be presented in two categories: (1) laboratory-scale treatment chambers and microbiological data and (2) pilot-plant scale processing systems and product shelf life data. Recommendations will be made as how to relate kinetics of microbial inactivation to dosage descriptors. Recommendations will also be made in areas of monitors and regulatory purposes.