Physicochemical Properties and In Vitro Digestibility of Starch Modified via Heat-Moisture Treatment and Inclusion Complexation

Starch is the most abundant source of carbohydrate for human nutrition. Starch is used as an energy supply for the human diet. However, rapid digestibility of starch (RDS) leads to high glucose levels in the human blood, and studies to develop slowly digestible (SDS) and resistant starches (RS) become very important. This thesis aims to scientifically study the starch modification process using low-cost food-grade ingredients and easily processable techniques to improve the resistance against α – amylase. Therefore, Heat-Moisture Treatment (HMT) followed by inclusion complexation with guest molecules was carried out to improve the physicochemical properties of the starch, thereby reducing its digestibility. In this research, HMT was used as pre-treatment before inclusion complexation with guest molecules, to pre-gelatinize the starch granules partially. Furthermore, HMT promoted more stable physical cross-linking of starch chains in the granules, leading to the possibility of inclusion complexation at elevated temperatures without destroying the whole starch granule structure. Various types of fatty acids were employed, such as unsaturated; linoleic acid (LA), saturated; stearic acid (SA) and salt form; sodium stearate (SS). Our research shows that sodium stearate results in the highest temperature-resistant complexes compared to stearic acid and linoleic acid; hence, it results in the highest resistance toward enzymatic degradation of potato starch. Based on the in vitro digestibility results, it can be summarized that the amount of RDS from high to low is SA > LA > SS, while for SDS and RS, it is SS > LA = SA.