Effects of Different Thermal Treatment Methods on Preparation and Physical Properties of High Amylose Maize Starch Based Films

Because of its biodegradable trait, starch has been widely used as the raw material for packaging. Effects of different thermal treatment methods (high temperature-high pressure heating (HH), microwave heating (MH) and alkali heating (AH) with and without glycerol on physical properties of high amylose maize starch films (HASFs) were investigated in this study. HASFs under HH had highest elongation at break (E%), and lowest tensile strength (TS), modulus of elasticity (EM) and opacity (OC). HASFs under MH had highest TS, water holding capacity (WHC) and OC, and lowest thickness (TN), E%, solubility in water (SW) and solubility in oil (SO), while HASFs under AH had highest TN, EM, SW and SO, and lowest WHC. Compared with water, plasticized HASFs with glycerol had higher TN. E%, WHC, SW and OC, and lower TS, EM and SO. XRD results revealed the V-type polymorph and the difference in intensity of diffraction peaks of HASFs under three methods. This study would be helpful to design and prepare HASFs.