以大米为原料，经浸润和焙炒等工序制得米茶。分别采用胰酶-糖化酶和胃蛋白酶-胰蛋白酶模拟淀粉和蛋白质在人体中的消化进程，研究动植物油脂、焙炒时间和焙炒温度对米茶淀粉和蛋白消化特性的影响，为米茶的加工提供基础数据。焙炒工艺会影响米茶的消化特性；焙炒可抑制米茶中淀粉的消化过程，有利于血糖指数的降低；添加油脂对米茶的消化有明显的抑制作用，对米茶消化液中葡萄糖含量有显著下降作用，但油脂的种类对淀粉的消化率抑制影响不大；过高的焙炒温度（200 ℃以上）和时间（35 min以上）会使米茶蛋白质的消化性能降低；焙炒对米茶消化后的绝对氨基酸含量基本无影响，焙炒会降低米茶酶解消化后游离赖氨酸和苏氨酸的含量，但适宜的焙炒条件对必需氨基酸的含量影响不大。

Rice tea made from soaked and roasted rice was subjected to pancreatic enzyme (glucoamylase and pepsin-trypsin) treatment in order to simulate the digestion of starch and protein in the human body. The effects of animal and vegetable oils, roasting time, and roasting temperature on the characteristics of rice tea starch and protein digestion were investigated to provide a theoretical basis for optimizing the rice tea roasting process. The digestive characteristics were significantly affected by the roasting process, which inhibited starch digestion and thus could reduce the glycemic index. Addition of oil also had significant inhibitory effects on the digestion of rice tea, which involved reducing the amount of glucose in the digestion products, but the type of oil used had little effect on the inhibition of starch digestibility. A higher roasting temperature (above 200 ℃) or time (above 35 min) could reduce the digestibility of the rice tea protein. However, roasting had little effect on the absolute amino acid contents of rice tea after digestion. Although the lysine and threonine contents were decreased by the roasting process, the contents of essential amino acids remained unchanged when the appropriate roasting process was conducted.

湖南省科技重大专项（2014FJ1008）