Question

Statement 1: In microwave heating, heat is not applied to the food item.

Statement 2: Radiation doesn’t gives even drying whereas microwave heating does.

(a) True, False

(b) True, True

(c) False, False

(d) False, True

This question was posed to me in homework.

The doubt is from Unit Operations in section Heat Transfer Equipment, Microwave Heating, Evaporation, Diffusion and Mass Transfer and Dehydration of Food Engineering

Answer 1

The correct choice is (b) True, True

The best explanation: In microwave heating, heat is not applied to the food item. Instead, heat is made to generate within the food item. Radiation doesn’t gives even drying whereas microwave heating does by addition of water. Water has a low dielectric constant due to the generation of friction due to the rotation of dipoles. Hence, water should be added for even heating.