Physicochemical properties and digestibility of modified tapioca starch, a double modification with heat moisture treatment and crosslinking

Abstract

Starch is a common resource of glucose for humans. Some diseases like diabetes and obesity are related to how high level of glucose in the blood. Starch modification is conducted to gain control over glucose in the blood to reduce the risk of the diseases. This study was successful in modifying tapioca starch with heat moisture treatment (HMT) and crosslinking with citric acid. The objective of this study was to investigate the changes that happen after the modification. HMT was conducted by varying treatment times and crosslinking was done by varying concentrations of citric acid used. HMT will induce rearrangement on starch crystal structure and could be identified with a microscope showed as a hole on the granule while crosslinking will generate new covalent bonds on the starch chain and could be identified with FTIR at 1720 cm-1 area. The results of alteration showed a decrease in swelling power and solubility, a decrease in paste clarity, an increase in paste viscosity, and an increase in thermal resistance. The digestibility of starch showed a significant decrease in dual treated starch. The dual treatment were on synergy to alter the physicochemical properties.