Heat transfer during frying of potato slices

The convective heat transfer coefficient during deep-fat-frying of potatoes was determined at different temperatures. The temperature, 0.1 cm below th e top and bottom surfaces of a 0.05 x 0.05 x 0.005 m potato sample was moni tored over rime. The thermal conductivity and specific heat of the sample w ere expressed as a function of rime, and the data were analyzed using the h eat transfer equation with an explicit finite difference method. Crust form ation occurred primarily at the bottom surface of the potato slice. Therefo re, the frying was examined at the bottom surface; before and after the cru st formation. The convective heat transfer coefficient ranged between 300 t o 335 W/m2 degrees C for the top, and 450 to 480 W/m2 degrees C for the bot tom surface before crust formation. After dust formation, it varied between 70 to 150 W/m(2)degrees C for the bottom surface within the studied temper ature range of 150 to 190 degrees C.