Sugar composition and in vitro glycaemic response of selected sugars, rice-based meals and traditional kuih

Abstract

High glycaemic index foods were found to increase the risk of getting diabetes, obesity, cancer and cardiovascular disease. This study aimed to determine the in vitro glycaemic response and sugar composition of selected food types, which include sugars, rice-based meals and traditional cakes and desserts (kuih). The food samples were purchased prepared and analysed using High Performance Liquid Chromatography (HPLC) to determine the sugar composition. The samples were also prepared and assayed using validated in vitro digestion method to determine the estimated glycaemic response. The in vitro method used 0.25g total available carbohydrate, which was established by Clegg Anthrone method. Among the studied samples, the total sugar content was icing sugar (100%), which has the highest percentage, nasi kerabu (7.49%) and kuih lapis (42.20%) for sugars, rice-based meals and traditional kuih, respectively. Dialyzable glucose concentration for the sugar samples was highest in the sugar in sachet (3.47 mg/mL) and lowest in the sugar with stevia (0.49 mg/mL). For the different types of rice-based meals, the highest dialyzable glucose concentration was in nasi lemak (13.06 mg/mL), and the lowest was in nasi kerabu (12.33 mg/mL). While for traditional kuih, kuih lapis (10.53 mg/mL) and kuih keria (6.30 mg/mL) were highest and lowest in the dialyzable glucose concentration, respectively. Significant correlations exist between dialyzable glucose concentration (at 120 minutes) and sugar composition (p<0.05) for the rice-based samples. Among the traditional kuih samples, sucrose content and total sugar content was correlated significantly. However, no correlation exists between dialyzable glucose concentration and sugar composition for the selected sugar samples. Factors such as particle size and presence of phytochemical in sugars, available nutrients (starch, protein and fat) in kuih and cooked dishes as well as the amount of added sugar in food are vital factors that affect the in vitro glycaemic response of the studied samples.