La Choviya Hawa

Design of High Voltage Pulse Generator for Pasteurization by Pulse Electric Field (PEF)

—Pulse electric field (PEF) is method of non-thermal food processing system by using high voltage pulse into the food through electrode applied to the chamber for a few seconds at room temperature. The purpose of this paper is to design a high voltage pulse generator using high voltage transformer in pasteurized apple juice-based on pulse electric field (PEF) with a treatment time control and analyzing the input specific energy needs during the process and change the number of microbes contained, in apple juice pasteurization results with processing time variations. Microcontroller is used as control unit to control treatment time by generating PWM pulse with duty cycle 0.5. It will obtained a simple and low cost equipment. To examine the equipment affectivity which applied to apple juice pasteurization is to adjust time processing compatibility from 10 seconds to 60 seconds.. Based on measurement result indicates that average of voltage and current used is 17kV and 0,48mA. Electric field strength delivered to chamber is 0,65kV/cm. The longer time treatment of PEF it will reveal the number of microbes contained in apple juice will be decrease and specific input energy will be increases. According to Zeleny analisys, the best time processing of apple juice pasteurization is 10 seconds processing.