Heat transfer coefficients during deep fat frying of sweetpotato: Effects of product size and oil temperature

Heat transfer coefficient, It during deep fat frying of sweetpotato was determined from designed experiments. Samples of three different disc sizes were fried at four oil temperatures between 150 and 180 degrees C. Heat transfer coefficient estimation was based on heat energy balance between the oil and sample during frying. Maximum h was reached at the earlier stage of frying (80-120 s). The range of maximum h reached was 710-850 W/m(2) degrees C. h at latter period of frying (200-300 s) was 450-550 W/m(2) degrees C. It was found to vary directly with oil temperature but inversely with sample size (p < 0.05). (c) 2007 Elsevier Ltd. All rights reserved.