Prediction of glycaemic indices (GI) of meals by starch hydrolysis indices

The glycaemic indices (GI) of food items are determined by an in vivo method which is laborious and time consuming. Thus, the aim of this study was to use an in vitro method and estimate the rate of hydrolysis of starch in basic foods as well as mixed meals with the intention of correlating these values with the published in vivo glycaemic indices of the same foods prepared in the same manner. The basic foods included both cereal based foods (n=5) and legumes (n=4) processed using different conditions. Mixed meals (n=7) contained a starchy staple with other supplementary meal accompaniments. The hydrolysis indices (HI) of basic foods and mixed meals were calculated for each food by taking the ratio between the HI of the test food to that of the standard food (white bread). A significant positive correlation was obtained for the in vitro HI and in vivo GI values of basic foods and mixed meals (r=0.949; p 0.001). A relationship of Y = 1.1367X - 12.38 was obtained indicating the possibility of calculating the GI of both basic foods and composite mixed meals from the respective hydrolysis indices.