The effect of substrate concentration on bioactive compounds of maltodextrin (based on sweet purple potato starch)

Maltodextrin is produced enzymatically through the liquefaction process of purple sweet potato starch. Maltodextrin has good solubility, can form films, has low hygroscopicity, acts as a dispersing agent, inhibits crystallization and has strong binding power. This study aims to determine the variation in substrate concentration on liquefaction time in producing optimal purple sweet potato maltodextrin products. The research procedure with various substrate concentrations (20%, 25%, 30%, and 35%) on the liquefaction time of maltodextrin (0, 20, 40, 60, 80, 100, and 120 minutes). This research used 60°C for starch liquefaction. The best concentration of purple sweet potato starch maltodextrin based on the degree of starch hydrolysis was a concentration of 30% with optimal values for reducing sugar and dextrose equivalent (DE), and the best concentration based on bioactive compound resistance was a concentration of 35% with optimal values for anthocyanins and antioxidant activity. The higher the substrate concentration and the longer the liquefaction, the higher the degree of hydrolysis of maltodextrin, but the bioactive compounds tend to decrease due to the unstable nature of anthocyanins against heating and of course, their antioxidant activity is also very low.