为探究莲子抗性淀粉结构对抗消化能力的影响机制，采用不同物理处理（压热、超高压、微波）结合普鲁兰酶改性莲子淀粉。结果表明，改性后莲子淀粉粒径增大，颗粒表面粗糙且形成不规则块状，“马耳他”十字消失，相对结晶度（从31.02%降至18.19%）和短程有序度（从1.56降至0.97）显著降低（P<0.05），其晶型从C型变为B型。体外消化实验表明，超高压协同酶改性淀粉的抗性淀粉含量最高（56.50%）。莲子抗性淀粉的抗消化特性与支链淀粉链长分布、短程有序结构及结晶结构存在显著相关性，淀粉分子的短程有序度、相对结晶度、B1链和B2链含量的提高，有利于增强莲子抗性淀粉的抗酶水解性，这些结构可实现对消化特性的调控。该研究分析了改性莲子淀粉多尺度结构与消化特性的关系，为采用新型食品加工技术制备抗消化能力强的莲子抗性淀粉提供参考依据，指导低GI莲子淀粉降血糖功能食品的生产。

To investigate the mechanism of the impact of the structure of lotus seed resistant starch on digestibility, lotus seed starch was modified using different physical treatments (autoclaving, ultra-high pressure, microwave) combined with pullulanase. The results showed that the particle size of the modified lotus seed starch increased, the surface of the particles was rough and formed irregular lumps, the “Maltese cross” formation disappeared, the relative crystallinity (from 31.02% to 18.19%) and short-range ordering (1.56 to 0.97) significantly decreased (P<0.05), and the crystalline type changed from C-type to B-type. In vitro digestion experiments confirmed that starch treated with ultra-high pressure combined with enzymatic modification contained the highest content of high-resistant starch (56.50%). The digestion properties of lotus seed resistant starch were significantly correlated with the branched amylose chain length distribution and the short-range ordering structure and crystalline structure. The increase in short-range ordering, relative crystallinity, and B1 chain and B2 chain content of the starch molecules was conducive to the enhancement of the resistance of lotus seed resistant starch to enzymatic hydrolysis, which may be related to the regulation of digestive properties. The relationship between the multiscale structure of modified lotus seed starch and its digestive properties, were analyzed herein to provide a reference for the preparation of lotus seed resistant starch with strong anti-digestive ability using novel food processing technology, and to guide the production of low-GI lotus seed starch food with hypoglycemic function.

企业委托项目（31-C-2020-006）