Effect of hydrolysis of sweet potato starch by pullulanase enzyme on the formation of slowly digestible starch

Abstract

The benefits of slowly digestible starch (SDS) are a slow or moderate increase in postprandial blood glucose levels and the maintenance of steady blood glucose levels. These created good conditions for diabetes control, satiety-hunger, physical and mental performance. Therefore, products related to slow digestion have attracted many researchers in recent years. In this research, technological factors affecting the formation of SDS from sweet potato starch (SPS) by the branching enzyme pullulanase were studied. These factors included SPS concentration, pullulanase enzyme concentration, pH, temperature, and hydrolysis time of pullulanase enzyme. The results showed that the maximum SDS yield was obtained by debranching for 5 hrs with an enzyme concentration of 20 ASPU/g, reaction temperature of 55°C, pH of 5.0, and a SPS concentration of 10% (w/w). In these conditions, the SDS content of SPS reached 28.04%. The findings indicated that sweet potato starch can be used as a raw material at a low cost and is feasible in the production of SDS which provides benefits for human health.