Effect of Single and Dual Modifications on the Physicochemical Properties of Sago Starch Modified by Ozonation and Acetylation

Abstract

Abstract Dual-step starch modification is an effort to eliminate weaknesses in single-step modification. This research aims to study the effect of single-step or dual-step modification methods on the physicochemical properties of sago starch. The single step consists of ozonation (Oz) and acetylation (As), while the dual step (sequentially), namely ozonation-acetylation (Oz-As) and acetylation-ozonation (As-Oz). The physiochemical responses measured were water content, carbonyl content, carboxyl content, acetyl content, water solubility index (WSI), water absorption index (WAI), and color. Ozonation causes the formation of carbonyl and carboxyl groups, and the modification process certainly causes the addition of carbonyl and carboxyl groups both in single step and dual-step. Acetylation causes higher acetyl group values in either single-step (As) or dual step (Oz-As and As-Oz) compared to original sago starch. There was a significant difference between the single and dual steps in the WSI and WAI values. The characteristics of Ozonated-acetylated (Oz-As) modified sago showed starch the highest WSI and WAI results. The water content in single-step modified sago starch compared to native sago starch has no significant difference in water content, whereas the dual-step modified sago starch has a higher water content than the native one.