Abstract:in recent years, carbohydrate foods with a low glycemic index (GI) have attracted attentions from consumers due to their health benefits, especially their ability to maintain stable postprandial blood glucose levels. With the increasing demand for specialized medical-purpose formula foods (referred to as formula foods) among individuals with specific health conditions, developing in vitro methodologies/models to accurately estimate the GI values, as an alternative to labor intensive in vivo blood test, has become of essentially important in the research and promotion of low-GI foods. Therefore, this study has systematically investigated the in vitro digestion characteristics of 10 formula foods with distinct ingredient compositions, obtaining various kinetics digestion parameters. These kinetics parameters were further analyzed in relation to human blood glucose test data, so that mathematical equations/models could be established to enable rapid prediction of their GI values. Results showed that the in vitro digestion characteristics varied significantly across different sample compositions. Among all digestion parameters, AUC90 (the area under the reducing sugar release curve within 0~90 min) demonstrated the greatest potential for estimating the eGI values of all samples. The predictive equation for GI values is given by eGI=0.020 6×AUC90-20.618 0 (R²=0.908 1). Moreover, it was also noted that the impacts of carbohydrate composition on eGI values differs depending on the ingredient type. Both solid corn syrup and tapioca dextrins significantly increased the concentration of reducing sugars, with comparable contributions to postprandial blood glucose elevation. In contrast, xylitol had a potentially smaller impact on blood glucose than maltitol. Additionally, the moderate inclusion of fructose did not show a significant effect on eGI values.
