The grain aleurone layers inhibited the penetration of digestive
fluid into the rice grain core, in intact rice grains, which influenced the starch hydrolysis rate during the simulated in vitro gastrosmall intestinal digestion. The results indicated that the degree of chewing might have an effect on the starch hydrolysis rate, which will also affect the degree of the rise in blood sugar in the human body upon the ingestion of starchy foods.