Ohmic Heating: Its Current and Future Application in Juice Processing

Abstract

ABSTRACT Ohmic heating (OH), also known as Joule heating, is a direct heating method in which an alternating current passes through a food mass, resulting in rapid and uniform internal heat generation. The OH method promotes microbiological safety, inactivates spoilage enzymes, limits the changes of nutritional and sensory properties, is highly energy efficient, and does not pollute the environment when compared with conventional heating. The OH technique promises to be a potential heating technique for food preservation and processing, especially for pasteurization/sterilization of fruit juices. In this review, the physicochemical, organoleptic, microbial, and enzyme changes in fruit/vegetable juices after OH are presented and discussed. This article intends to provide aggregate data for researchers, to be a reference for information on changes in juice after OH, and to encourage the application of OH in the food industry. Although OH has the effect of maintaining juice quality, its effectiveness is affected by the electrochemical properties of the food. Therefore, in order to effectively achieve OH processing, OH conditions need to be established in accordance with the characteristics of the food material. Further studies are needed to evaluate the effects of OH in juice processing on a large scale, rather than a laboratory scale.