A review on ohmic heating technology: Principle, applications and scope

Ohmic heating is a novel and alternating thermal processing technology wherein food materials are heated by passing electric current through materials. Ohmic heating has extreme potential for achieving rapid and uniform heating in foods, providing microbiologically safe and high quality foods. Ohmic heating presents a wide range of potential applications including pasteurization, sterilization, aseptic processing, cooking, thawing, blanching, evaporation, extraction, fermentation, and in the military field or long-duration space missions. This review discusses the brief history, basic principle, some process parameters, applicable food products, potential commercial applications and current industrial status of ohmic heating in food industry throughout the world. The review also highlights the scope and work done on ohmic heating in India. The corrosion problems in electrodes and heterogeneous heat generation rate and distribution are interesting area for further research. Ohmic heating is a good comparable with the other ideal technologies like microwave heating, radio-frequency heating and induction heating. More and intensive investigations are required to assess performance and to reduce the overall cost of ohmic heating for viability of commercial application of this technology also in developing countries like India.

The key advantages of ohmic heating are better product quality, less cooking time, lower capital cost, better energy efficiency and environment friendly process.

Ohmic heating technology is chiefly and commercially industrialized for pasteurization and sterilization but continuous efforts are being made to adopt other applications also in near future.