Heating characteristic and mathematical model of enzyme inactivation ratio during ohmic heating of kiwifruit puree

Variation rule of heating rate and electric conductivity were explored during ohmic heating of kiwifruit puree. Mathematical model of inactivation ratio were established for polyphenol oxidase and peroxidase. Results indicated that the heating rate increased with the increase of the electric field strength. The electric field strength had no obvious effect on electric conductivity. With temperature increasing, electric conductivity increased linearly. Regression equations existed at a significance level of 0.05, which could be used for predicting inactivation ratio of polyphenol oxidase and peroxidase during ohmic heating of kiwifruit puree. These results would be theoretical basis for the deep processing of kiwifruit puree.