Ohmic Heating: Thermal Processing of Fruits and Vegetables

This chapter focuses on the principle of Ohmic heating and ohm&s;s law; on major factors affecting Ohmic heating; on the applications and benefits of Ohmic heating in food processing; on mathematical modeling of the Ohmic heating system; and on applications and advantages of Ohmic heating. Ohmic heating, microwave heating or dielectric heating or radio frequency heating are the emerging novel thermal processing technologies. Consumers around the world demand processed foods that should be of high quality with long shelf-life without addition of any chemical additive and also without being exposed to extreme temperature conditions. Electrical conductivity of food is most important property affecting the rate of Ohmic heating. Electrical conductivity can be defined as a measure of how well a substance transmits electric charge, expressed in Siemens per centimeter. Ohmic heating, which is a newly enhanced aseptic processing technology capable of an effective thermal treatment of particulate foods, has received considerable interest among the food industries.