The Study On Glycemic Index And Glycemic Load Measurement Of Oats And Buckwheat Processed Foods

Objective:In this study, the glycemic index(GI) and glycemic load(GL) values of 20 kinds of oat and buckwheat processed foods were determined and compared to research their effects on postprandial glucose. This study was aiming at filling in the blanks of the values of oat and buckwheat processed foods in food GI and GL database, and providing the nutritional evaluation data for the following study of dietary intervention on pre-diabetes populations in community, and finally providing scientific basis for the diet intervention applied in the prevention and treatment of chronic metabolic diseases.Method:The GI and GL values of 20 kinds of oat and buckwheat processed foods were determined through the standard method which was internationally recognized. Using 50 g glucose powder as a reference, all the tested foods contained 50 g carbohydrate comparably. Each kind of tested foods was tested on a group of 10 volunteers. After the determination of fasting blood glucose, the volunteers were asked to eat glucose powder or tested foods. The postprandial blood glucose was determined at the points of 15, 30, 45, 60, 90, and 120 minutes after eating. With time as abscissa and blood glucose levels as the ordinate, the blood glucose response curve was formed by a line which connected all the blood glucose values at different point straightly. Calculating the increment area under the blood glucose response curve of tested food and glucose powder, separately, the value of the former divided by the latter was the GI value of this tested food. Thiscalculation was completed by specialty software. Moreover, the GL of foods were the product of its GI value and the content of its carbohydrate divided by 100. This study was divided into 5 periods. There were 4 kinds of foods were measured in each period, and between two kinds of tested foods there were one day apart.Results:1. GI values of tested foods:① Low GI foods(GI<55): 18 kinds of tested foods were defined as low GI foods, including Tartary buckwheat vermicelli, Tartary buckwheat crisp bar, Tartary buckwheat and red bean cereal, Common buckwheat and mung bean cereal, Buckwheat wantuan, Tartary buckwheat cereal, Wantuo, Grain paste, Tartary buckwheat and red bean paste, Tartary Buckwheat noodle, Tartary buckwheat healthy porridge, Common Buckwheat noodle, High fiber tartary buckwheat cereal, Mixed rice, Oat noodle, Tartary buckwheat beverage, Artificial grain rice, and Coarser grains porridge.② Moderate GI foods(GI between 55~70): Oat rice crust and Oat and pea paste belonged to moderate GI foods.2. GL values of tested foods:(Food intake was equal to a portion which would produce 90 kilocalories energy)① Low GL foods(GL≤10):15 kinds of foods including Tartary buckwheat vermicelli, Tartary buckwheat and red bean cereal, Common buckwheat and mung bean cereal, Wantuo, Tartary buckwheat and red bean paste, Tartary Buckwheat noodle, Tartary buckwheat healthy porridge, Common Buckwheat noodle, Oat noodle, Tartary buckwheat beverage, High fiber tartary buckwheat cereal, Coarser Grains Porridge, Artificial grain rice, Mixed rice, and Grain paste, belonged to low GL foods.② Moderate GL foods(GL between 10~20): These 5 types of foods were defined as moderate GL foods, such as Oat rise brust, Oat and pea paste, Tartary buckwheat crisp bar, Buckwheat wantuan, and Tartary buckwheat cereal.3. Blood glucose response: 30 minutes after eating glucose powder solution, the bloodglucose level of volunteers peaked fast and highly and then the blood glucose dropt fast. The postprandial blood glucose curve showed rising quickly and falling rapidly, which indicated a high fluctuation of postprandial blood glucose level. However, the blood glucose level of tested foods mostly peaked in 30~45 minutes after eating, peaking more slowly and below glucose powder. The curves presented a small fluctuation as rising and falling slowly, which meat that the postprandial blood glucose remained relatively stable.4. Correlation between food GI and GL values: In this study, there was a positive correlation between the GI and GL values of 20 kinds of tested foods, and the correlation coefficients was 0.934(P<0.0001).Conclusions:Oat and buckwheat processed foods had lower GI and GL values, thus they would have less effects on the postprandial blood glucose level, and conduce to maintain its stability and longer satiety. The tested foods were made of variety of coarse grains by modernized production technology on an assembly line. They had those advantages, such as high nutrition value, good taste, standardized production technology, quantifiable raw material formulation, easy to preserve, transport and carry, and so on. These oat and buckwheat processed foods will have a broad application prospect used in the prevention and treatment of chronic metabolic diseases.