Effect of voltage gradient on electrical conductivity of tomato paste under ohmic heating

Subject Areas : Journal of Food Safety and Processing

Mehdi Torkian Boldaji ¹ (Assistant Professor, Department of Mechanics, Faculty of Basic Sciences, Islamic Azad University, Varamin-Pishva and Qarchak branch, Varamin, Iran)

Received: 2022-02-08 Accepted : 2022-09-24 Published : 2023-02-20

Keywords: Electrical Conductivity, ohmic heating, tomato paste, voltage gradient,

Abstract :

Ohmic heating is a new method in the processing of agricultural products, which produces heat inside the product by passing an alternating current through the food and causes it to heat up. The electrical conductivity of the food product is one of the influencing factors in the efficiency of this system. In this article, the effect of voltage gradient on the electrical conductivity of tomato paste in processing by ohmic heating method is investigated. For this purpose, four voltage gradients of 5, 7, 9 and V/cm11 were considered. The electrode used in this research is stainless steel and the concentration of sodium salt is 2% by weight. The results showed that the effect of voltage gradient on the slope of electrical conductivity is significant at the 1% probability level and the electrical conductivity increases with the increase of temperature and the passage of time, although the electrical conductivity decreased with the increase of the voltage gradient.