Enzymatic modification is an effective method to inhibit starch retrogradation. However, lack of quantification of relationships between enzymatic modification and starch retrogradation makes the enzymatic improvement unpredictable. In this study, maltogenic α-amylase (MA) was used to treat wheat starch granules to restrain retrogradation, aiming to elucidate the mechanism of MA hydrolysis on wheat starch granules and to establish a quantitative relationship between the degree of hydrolysis (DH) and retrogradation. Scanning electron microscopy and small angle X-ray scattering results showed that MA hydrolyzed starch granules by a “surface pitting” mode simultaneously acting on crystalline and amorphous regions. Debranching and high performance anion exchange chromatography analysis of MA-treated wheat starch granules demonstrated that the amount of short branches with degree of polymerization＜9 increased and the proportion of medium and long branches decreased. Importantly, the extent of impaired short- and long-term retrogradation of MA-treated starch was clearly linearly correlated with the DH. This finding provides a quantitative method for predicting the degree of retrogradation improvement by enzymatic modification.

酶促改性是抑制淀粉回生的有效方法。然而，酶促改性和淀粉回生之间关系的量化缺乏使得酶促改进不可预测。本研究采用麦芽糖α-淀粉酶（MA）处理小麦淀粉颗粒抑制回生，旨在阐明MA对小麦淀粉颗粒的水解机理，并建立水解度（DH）与回生之间的定量关系。 . 扫描电子显微镜和小角 X 射线散射结果表明，MA 通过“表面点蚀”模式同时作用于结晶和非晶区域，水解淀粉颗粒。MA处理的小麦淀粉颗粒的脱支和高效阴离子交换色谱分析表明，聚合度＜9的短支链数量增加，中长支链比例下降。重要的是，MA 处理淀粉的短期和长期回生受损程度与 DH 明显线性相关。这一发现提供了一种通过酶促修饰预测回生改善程度的定量方法。