Effect of batter formulation and pre-drying time on oil distribution fractions in fried batter

Abstract

Batter coating and pre-drying have recently been used as techniques for decreasing fat content of fried foods. The objectives of this study were to assess the effect of batter formulations and pre-drying time on surface, penetrated and total fat content of batter coating, and to evaluate different mathematical models for predicting moisture diffusivity and oil transfer during frying. Two different sets of batter systems were used. The first set consisted of batter with different ratios of wheat to rice flour whereas the second set was wheat-flour-based batter with different pre-drying times. The batter samples were deep fried at 180 ± 2 °C in canola oil for different frying times between 0 and 4 min. Batter with wheat flour alone was found to have higher surface fat and total fat contents, while its penetrated fat content was lower than that with other batters. Batter with no pre-drying showed higher surface, penetrated and total fat content than other systems. Moisture diffusivity ranged between 2.01 × 10−6 and 2.85 × 10−6 m2/min. Page model was found as the best fit model to evaluate the oil transfer rate constants.