Mechanistic insights into the supramolecular structure and physicochemical properties of twin-screw extruded high amylose corn starch with different amylose content by improved electron beam irradiation

The influence of improvement via electron beam (EB) of twin-screw extruded (TSE) high amylose corn starch on its multiscale structure and physicochemical properties was assessed. The granular integrity of TSE was lost and the crystal type changed. TSE increased amylose content, A-chain content, rapidly digestible starch content and slowly digestible starch content, but decreased crystallinity, molecular weight and resistant starch content. These structural changes made TSE samples more susceptible to subsequent EB-irradiation. The molecular weight and long chain of amylopectin in TSE-sample were decreased by EB-irradiation. Amylose content, crystallinity and short-range order were reduced by EB-irradiation. These structural alterations facilitated the enhancement of TSE properties. The TSE-EB sample had better solubility, anti-digestive properties, lower swelling power and apparent viscosity. The combination of TSE and EB is an effective method to improve starch's structure and properties and this modified starch could be implemented to tailor starch to the desired food applications.