Characterisation of amylose and amylopectin with various moisture contents after frying process: effect of starch–lipid complex formation

Frying is commonly used to process starchy foods. This work explored the interactions of amylose (AM) and amylopectin (AP) with lipids during frying. Maize-derived AM and AP that were adjusted to various moisture contents were fried at 180 °C. The significant effects of moisture content and formation of starch–lipid complexes were confirmed. Rheological analysis indicated that the elasticity of the fried AM paste decreased. This change was observed in AM but not in AP. Viscoelasticity decreased as the initial starch moisture content was increased. The presence of a V-type structure was confirmed by XRD. In general, relative crystallinity decreased as moisture content was increased. On the other hand, the increasement of starch–lipid complex could elevated the degree of crystallisation. AM was more likely than AP to undergo complexation with lipids during frying. Increasing the moisture content of starch within 20%~60% promoted the formation of starch–lipid complexes.