Effect of ohmic heating on fish proteins and other biopolymers

Under Ohmic heating, heat is developed when alternating current passes through electrically conducting food materials (de Alwis and Fryer, 1990). Heat is generated within the food due to its electrical resistance, resulting in a relatively rapid heating rate, depending on the chemical composition. The rate of temperature increase during the Ohmic process ranges from 1°C to 5°C/s (de Alwis and Fryer, 1992), whereas; the surface of a can in conventional sterilization is about 0.2°C/s (Datta and Hu, 1992). In general, the Ohmic process is known to reduce processing time, resulting in superior product quality compared with those processed by conventional means. However, practical application in such processes has been limited due to the problems associated with process and equipment design (Sastry and Palaniappan, 1992).