Application of Pulse Electric Fields in Food Processing

Abstract

Pulse electric field (PEF) is one of the most promising non-thermal processing methods for the preservation of food products. PEF processing inactivates microorganisms present in food products with minimal changes to their physical, sensory, and functional properties. Exposure of food products to high electric field pulses develops pores in the cell membrane of the microorganism either by enlargement of existing pores or by creation of new ones. The PEF processing system consists of a high-power pulse generator, a treatment cell, and voltage- and current-measuring devices. Very short pulses (micro to milliseconds) are applied to liquid or semi-solid food placed between two electrodes at electric field intensities ranging from 10 to 80 kV/cm. For the application of high-intensity pulsed electric fields, short time pulses are generated between two parallel-plate electrodes enclosing a dielectric material. In PEF treatment, parallel-plate chambers are used for batch processing, and coaxial chambers for continuous processing.