不同大米米饭碳水化合物消化速度的研究

STUDY ON THE DIGESTION RATE OF CARBOHYDRATES IN COOKED RICE OF DIFFERENT VARIETIES OF RICE

通过体外模拟人体胃肠道环境,比较不同品种大米烹制成的米饭碳水化合物的消化特性,为糖尿病患者选择主食提供一定的参考依据.以绿玉千为参考标准,每份大米均含1 g可利用碳水化合物,以同样烹制方式烹制成米饭后,人体咀嚼后加入蛋白酶在37℃孵育30 min,再转入透析袋中,并加入淀粉酶在37℃孵育3 h,孵育期间每隔30 min从透析液中吸取样液,用DNS法测定样液中的还原糖含量.结果表明,将参考标准绿玉千的血糖指数定为100,其他3种大米的血糖指数分别为:桥米(23.96±1.11)、红米(51.28±1.77)、合美占(79.44±3.02),其中桥米的血糖指数显著低于红米和合美占.因此,桥米是低血糖指数食物,是糖尿病患者理想的主食选择.

In this paper,we sludied the digestion characteristics of cooked rice of different varieties of rice by simulating gastroenteric environment of human in vitro to provide reference for food selection for diabetes patients. Selecting the variety of Ltiyuqian rice as reference,the method comprised preparing cooked rice from samples each containing 1g available carbohydrates in the same cooking manner;chewing the cooked rice; adding protease into the chewed rice;incubating at 37℃for 30 min;adding to a dialysis bag;adding amylase, incubating at 37℃for 30 h,and sampling from the dialyzate at a fixed time interval of 30 minutes during incubation; and determining the content of reduced sugar in the sample by DNS method.The results showed that the glyeemic index of Liiyuqian rice was set as 100;the glycemic indexes of other three kinds of rice were respectively： bridge rice（23.96±1.11）,red rice（5 1.28±1.77 ）,and Hemeizhan rice（79.44±3.02 ）;and the glycemic index of bridge rice was remarkably smaller than those of the red rice and Hemeizhan rice.Accordingly, bridge rice has lower glycemic index and is an ideal food for diabetes patients.