Indian Journal of Science and Technology

Abstract

Objective: Native starches possess poor characters which need to be improved by modification to increase the spectrum of their industrial applicability. The present study aims to synthesize and characterize oxidized enset [Ensete ventricosum] starch. Methods: Native enset starch was isolated and modified through oxidation using 30% w/w hydrogen peroxide (H₂O₂ ) solution in alkaline pH for 30, 60, 90 and 120 minutes. The carbonyl and carboxyl contents as well as XRD and FT-IR patterns were determined for the oxidized starches. Solubility and swelling characteristics, density and related properties were also investigated in comparison to the native starch. Findings: H₂O₂ oxidation of enset starch resulted higher value for carbonyl contents (0.46 to 0.56) than carboxyl contents (0.17 to 0.18) and it increased the solubility while decreasing swelling power of enset starch. Oxidized starches showed increase in solubility in the order Oxi 120>Oxi 90>Oxi 60>Oxi 30. Oxidation at different reaction times did not bring change in XRD patterns instead alteration of intensity of major diffraction peaks was observed. This implies the present condition of oxidation didn’t bring change in crystal type but the intensity change may indicate that degree of crystallinity was reduced. The oxidized enset starch showed poor flow and compressibility as it is evident in the calculated values of Hausner ratio, Carr’s index and angle of repose. Application/ Improvement: Ensete ventricosum, widely cultivated in southern and south western Ethiopia and rich in starch, can be oxidized using a simple and eco-friendly technique for its potential applicability in the food and pharmaceutical industries.

Keywords: Carbonyl Content, Carboxyl Content, Enset Starch, Hydrogen Peroxide, Oxidized Starch