酶解耦合湿热处理对板栗淀粉消化性能与回生性能的影响

板栗淀粉的消化和回生性能制约着板栗食品产业发展，合理选择食品加工方法调控板栗淀粉的消化和回生性能对开发高品质营养健康的板栗食品具有重要意义。本文探究了普鲁兰酶酶解及耦合湿热处理对板栗淀粉的消化率、长期回生和多尺度结构的影响。结果显示，酶解处理增加了板栗淀粉的直链淀粉含量，改变了淀粉链长分布，提高了淀粉短程有序结构和结晶结构，从而降低了淀粉消化率；进一步的湿热处理促进淀粉链相互作用，提高了淀粉短程有序结构、结晶结构和纳米聚集体结构，导致了更低的淀粉消化率。在储存过程中，由于酶解导致更短的A链增加及易于重排的B1链降低，使得淀粉形成的结晶结构和纳米聚集体结构较少，从而降低了淀粉的回生程度；湿热处理促进了A链分子与其他分子的相互作用，加剧抑制淀粉分子重排程度，导致回生程度继续降低。因此，酶解耦合湿热处理可作为一种有效的调控淀粉消化和回生性能的方法，促进慢消化和低回生度板栗淀粉食品的开发。

Effects of Enzymolysis Coupled with Hydrothermal Treatment on Digestion and Retrogradation of Chestnut Starch

The digestion and retrogradation performance of chestnut starch constrains the development of chestnut food industry. It is of great significance to select reasonable processing methods to regulate the digestion and retrogradation properties for the development of nutritious and healthy chestnut foods with high quality. Therefore, the effects of pullulanase enzymatic hydrolysis coupled with hydrothermal treatment on digestibility, long-term retrogradation and multi-scale structure of chestnut starch were investigated. Results showed that enzymatic hydrolysis increased amylose content, and changed chain length distribution. Short-range ordered and crystalline structures were also improved, and the starch digestibility were also reduced. Hydrothermal treatment promoted starch chain interactions, and improved short-range ordered, crystalline and nano-aggregate structures of starch, leading to the lower starch digestibility. During long-term retrogradation, due to the increase of shorter A chains and the decrease of B1 chains which are easy to rearrange, starch crystalline and nano-aggregate structures decreased, which retarded starch retrogradation. Hydrothermal treatment promoted the interactions among A chains and other molecules, and further inhibited the degree of starch molecule rearrangement, which could lead to the lower degree of retrogradation. Therefore, enzymatic hydrolysis coupled with hydrothermal treatment can be used as an effective method to regulate the digestion and retrogradation performance of starch, which could promote the development of chestnut starch-based foods with slower digestion rate and lower retrogradation degree.