Effects of acetylation, carboxymethylation and crosslinking on some physicochemical properties of starch from tubers of <i>Icacina senegalensis</i> and <i>Cyrtosperma senegalense</i>

Abstract

Starch extraction from Icacina senegalensis (IS) and Cyrtosperma senegalense (CS) tubers was carried out with water at room temperature. The tubers of Icacina senegalensis and Cyrtosperma senegalense gave a starch yield of 40.9% and 25.5% respectively. The amylose, amylopectin composition of starches from IS and CS tubers were determined to be 10.8%, 89.2% and 24.6%, 75.4 % respectively. The starch extracts were chemically modified to produce cross-linked, carboxymethylated and acetylated starch derivatives. The formation of new chemical bonds in the starch derivatives was confirmed with Fourier Transform Infra-red spectroscopy (FTIR). Both swelling power and gelatinization temperature of IS starch and CS starch increased with acetylation, crosslinking and carboxymethylation while the degrees of substitution for the starch derivatives ranged between 0.33 and 1.45 making the native and modified starches suitable for many industrial applications.