Starch–palmitic acid complex formation and characterization at different frying temperature and treatment time

Abstract Starch is the most common substance in fried food. Thus, understanding the properties of starch–lipid complex at frying temperatures is significant. Starch–palmitic acid complexes (SPACs) treated for different times (6 min–15 min) or at various frying temperature (90 °C–210 °C) were investigated. SPAC formation initially increased and then decreased with prolonged treatment time. The increase in treatment temperature ranging from 120 °C to 180 °C favored the complex formation; and there was a sharp decrease in 210 °C. With prolonged time at frying temperature, the complex gradually formed and then decomposed. The thermostability exhibited an increasing tendency with elevating temperatures. The viscoelasticity of gelatinized samples treated for 9 min or prepared at 150 °C decreased significantly. The digestion rate of SPAC for extending time, influenced by the complex formation, increased first and decreased afterwards. The digestibility of SPAC improved with increasing temperature, except that starch–lipid complex formed at 150 °C was obviously reflected in the increasing resistant starch. Starch–lipid complex formation at frying temperature and the variation of properties can be adjusted for different needs by means of changing treatment time and temperature.