EFFECTS OF REPLACING SUCROSE BY ISOMALTULOSE IN GREEN TEA BEVERAGE ON POSTPRANDIAL GLUCOSE, INSULIN LEVEL AND ANTIOXIDANT CAPACITY IN HEALTHY SUBJECTS

Abstract

Consumption trend of sweetened tea beverage has been increased. There is a link between sweetened beverage consumption and long-term weight gain. Isomaltulose (low-glycemic sweetener) has been interested in replacing sugar in beverage. Therefore, this study investigated the effects of replacing sucrose by isomaltulose in green tea beverage on glycemic response and antioxidant capacity in healthy subjects. Eighteen healthy subjects were randomized to drink a beverage (400 mL) containing: 1) 50 g sucrose (SU), 2) 50 g isomaltulose (ISO), 3) green tea (GT), 4) green tea+50 g sucrose (GT+SU) or 5) green tea+50 g isomaltulose (GT+ISO) with crossover-design. Total polyphenol of green tea beverage was 1.202±0.05 mg gallic acid equivalent/mL. GT, GT+SU and GT+ISO had no significant difference of antioxidant capacity (Ferric reducing antioxidant power, FRAP). The results showed that consumption of GT+SU suppressed postprandial plasma glucose and insulin concentration, compared with SU. Moreover, consumption of GT+ISO showed a significant higher reduction of postprandial plasma glucose and insulin concentration than ISO and GT+SU. In addition, our in vitro study showed that green tea had inhibitory effect on isomaltase activity. Furthermore, the antioxidant capacity increased after drinking green whereas it decreased when drinking GT+SU. In contrast, replacing SU by ISO in GT preserved antioxidant capacity of GT. Besides, consumption of GT+ISO produced a greater reduction of malonaldehyde (MDA) than GT+SU. In conclusion, the glycemic response and antioxidant capacity improved when replaced sucrose by isomaltulose in green tea beverage.