湿热处理对芋头淀粉糊化和体外消化性能的影响

Effects of Heat-Moisture Treatment on Gelatinization and in vitro Digestibility of Taro Starch

以荔浦芋为原料制备芋头淀粉,将不同含水量(10%~30%)的芋头淀粉在110℃条件下湿热处理2 h,研究湿热处理(HMT)后芋头淀粉糊化特性和体外消化性能的变化。结果表明,HMT对芋头淀粉颗粒形貌影响不显著,但颗粒之间发生聚集现象,且随HMT含水量的升高聚集体积增大,粒度也随之增加。随着含水量增加,HMT使芋头淀粉的膨润力和溶解度降低,糊化温度升高,糊化焓值降低,淀粉糊黏度降低,但淀粉糊稳定性增加。HMT也改变了淀粉的体外消化性能,增加了慢消化淀粉和抗性淀粉含量。说明HMT可用于扩展芋头淀粉的应用范围,如制造需要在高温下加工的产品或制备低GI值食物。

Taro starch was prepared from Lipu Taro.Taro starch with different moisture contents(10%~30%)was treated with moist heat at 110℃for 2 h.The Gelatinization Characteristics and in vitro digestibility of taro starch after heat-moisture treatment(HMT)were studied.The results indicated that HMT had no significant effect on the morphology of taro starch granules,but aggregation occurred between the granules.With the increase of HMT moisture content,the aggregation volume and particle size increased.With the increase of water content,HMT decreased the swelling power and solubility of taro starch,increased the gelatinization temperature,decreased the gelatinization enthalpy,and decreased the viscosity of starch paste,but increased the stability of starch paste.HMT also changed the in vitro digestibility of starch and increased the contents of slow digestible starch and resistant starch,indicating that HMT can be used to expand the application range of taro starch,such as manufacturing products that need to be processed at high temperature or preparing foods with low GI value.