Improvement in uniformity of co-linear pulsed electric field treatment chamber by sub-electrodes and its optimization

Abstract

The uniformity of performance parameters such as electric field and temperature for a co-linear pulsed electric field (PEF) processing system is one of main factors affecting the processing effect and quality of liquid food. We have proposed a co-linear PEF treatment chamber configuration with sub-electrodes to improve the uniformity and processing efficiency. We have first examined how the position of the sub-electrodes alone affects the uniformity of the performance parameters. Then, we have investigated the variation of the uniformity while changing simultaneously the electrode radius, inter-electrode gap, and position of sub-electrodes. As a result, we have found that the most uniform field could be obtained when the electrode radius is 5.5 mm, the inter-electrode gap is 15 mm, and the sub-electrodes situate at the middle of the chamber. In this chamber, the region between 95% and 105% of the average electric field covers 83%, which shows much improvement compared to the formers' results, 69.5% and 76%, respectively. Also, the optimal treatment chamber provides greater average electric field under the same voltages as the voltages reported by the formers.

Practical applications

A novel treatment chamber with sub-electrodes is proposed for pulsed electric fields food processing. The improved treatment design was obtained by changing position of sub-electrodes, inner radius of electrodes and distance between electrodes. The more uniform electric field was obtained in treatment region. The temperature distribution was more uniformed by increasing flow rates and uniformed electric field strength. The treatment throughput was increased by sub-electrodes.