The samples were placed in the test cell; the thermocouples were inserted and fitted into the geometric center of the sample. The ohmic heating was operated at four voltage gradients 30, 35, 45 and 55 V/cm at 60 Hz from 20 to 85 °C. Temperature, current and voltage applied were monitored and this information was passed to the microcomputer with an RS 232 port at 1second intervals.