An examination of factors affecting radio frequency heating of an encased meat emulsion

The potential of radiofrequency (RF) heating for rapid cooking of a cased comminuted meat emulsion (white pudding) to a pasteurisation temperature of 73 °C was examined. Immersion of the product in water was essential in order to prevent thermal damage to the casings by electrical arcing effects during heating. Using a polyethylene heating cell with non-circulating water the applied RF power, primary electrode distance as well as the mineral content, temperature and volume of the surrounding water all influenced the efficiency of the RF heating. Under optimised conditions maximum/minimum temperature gradients (ΔT) across the products in excess of 15 °C were observed. These could be reduced to around 6 °C by heating the white puddings in a cell operating with recirculating hot water (80 °C). Using an oven power output of 450 W a 4.3-fold reduction in cooking time compared to conventional steam oven cooking could be achieved.