Ohmic Heating of Lemon and Grapefruit Juices Under Vacuum Pressure- Comparison of Electrical Conductivity and Heating Rate.

Ohmic heating fundamentally depends on electrical conductivity. In this study, grapefruit and lemon juices were ohmically heated under vacuum conditions. The electrical conductivity was measured at voltage gradients (10, 20, and 30 V/cm) and vacuum pressure (0 [atmospheric pressure], -30, and -60 kPa) for four temperature ranges (30, 40, 50, and 60 °C), meanwhile the heating rate was also reported at the same level of pressure and voltage gradient.