Effect of Starch Chain Structure and Non‐Starch Components on the Hydrolysis of Starch by α‐Amylase

Abstract There are differences in enzymatic hydrolysis of starch slurries determined by the starch‐iodine method, but the reason for this phenomenon is not clear. In this study, corn, cassava, and potato starches that are commonly used in warp sizing as the research object, separating amylose and amylopectin, removing lipids or lipids, and proteins in starch, to explore the effect of starch molecular structure and nonstarch components on the hydrolysis of starch catalyzed by α‐amylase. The results show that about 10% of the corn starch is resistant to hydrolysis, much more than cassava and potato starches. Differences in amylose structure have no significant effect on hydrolysis, but the degree of hydrolysis of corn amylopectin is significantly lower than that of the amylopectins in cassava and potato starch, because of its higher molecular density. Lipid removal has a slight effect on the hydrolysis, but protein removal obviously improves the hydrolysis of corn starch, with only ∼2% of resistant starch remaining. Endogenous protein has the most excellent inhibitory effect on the hydrolysis of starch slurry, followed by lipids and the higher molecular density of amylopectin.