EFFECT OF SODIUM-CHLORIDE ON THE MICROWAV E-HEATING OF MASHED POTATOES

The microwave heating of mashed potatoes samples containing sodium chl oride (0,2 and 0,45 M) is compared with heating of control samples wit hout addition of salt under the same conditions (heating at 600 W duri ng 1 to 2 min). The addition of salt reduces the rate of heating and i ncreases its spatial nonuniformity. Temperature levels mapping is show n in reponse surface plots. This thermal behaviour of mashed potatoes which is due to a decrease of its toss factor and of its penetration d epth is likely to endanger the microbial safety of the food.