Structure and properties of esterified high-amylose corn starch combined with fatty acid prepared by enzymolysis and esterification reaction

To expand the application of high amylose corn starch (HACS), stearic acid, palmitic acid, and lauric acid esterified starches (SS, PS, and LS) were prepared from HACS through enzymatic hydrolysis followed by esterification. FT-IR and ¹H NMR confirmed the esterification reaction occurred between starch hydroxyl groups and fatty acid carboxyl groups. XRD analysis revealed that enzymatic hydrolysis increased starch crystallinity to 16.68 %, while esterification decreased it to 13.35 %, 11.47 %, and 11.23 % for SS, PS, and LS, respectively. Enzymatic hydrolysis improved thermodynamic properties, while esterification reduced gelatinization temperature, enthalpy, and thermal stability. Esterification enhanced the freeze-thaw stability, anticoagulation settleability, and oil holding capacity (p < 0.05). Furthermore, the degree of substitution, thermal stability and freeze-thaw resistance of LS was superior to SS and PS. This suggested that esterified starches prepared with shorter carbon chain fatty acids had better processing properties, and they could be used to develop functional foods with low glycemic index.