Department of Post Harvest Process and Food Engineering, G. B. Pant University of Agriculture and Technology, Pantnagar-263145 Distt. Udham Singh Nagar, Uttarakhand, India
*Corresponding author: sskautkar15@gmail.com
Online published on 18 May, 2015.
Ohmic heating is now regarded as highly attractive advanced technique for food processing wherein electric current is passed through the liquid particulates foods with primary purpose of heating them. The success of ohmic heating depends on the rate of heat generation in the system, the electrical conductivity of the food, method by which the food flows through the system and composition of the food. In this study, the ginger paste at different salt treatment (0–2% w/w) was heated in a laboratory scale ohmic heater by applying voltage gradients (5–13 V/cm). The temperature dependent electrical conductivity was obtained at different time interval of 0, 5 and 10 minute at different temperatures (30–60°C). Bubbling was observed above 70°C especially at high voltage gradients. The electrical conductivity measured in terms of point and bulk electrical conductivity. Point electrical conductivity was greater than bulk electrical conductivity. The point and bulk electrical conductivity values were in the range of 4.41 to 6.63 and 3.75 to 5.87 mS/cm respectively.
The electrical conductivity measured in terms of point and bulk electrical conductivity
Point electrical conductivity was greater than bulk electrical conductivity
The electrical conductivity of the ginger paste linearly increased with temperature and ionic concentration
The determination of electrical conductivity changes and system performance coefficients during ohmic heating are important in the design of ohmic heaters.
Joule heating, point and bulk electrical conductivity, ginger, temperature, voltage gradient
