Effect of Annealing on the Physicochemical Properties of Some Under-utilised Legume Starches

Abstract

Starches isolated from Jack bean (JBS), Detarium microcarpum (DMS), Bambara groundnut (BNS) and African yam bean (AYBS) seeds were annealed at 50^oC for 24 h. Proximate composition of the starch samples revealed that the moisture content of the starches ranged from 8.65 to 9.88%. There was increase in the moisture level of the annealed starches compared to native starches. The protein, ash, fat and fibre contents reduced in all starch samples following annealing compared with the native starches. Annealing decreased the swelling power and solubility index (BNS > AYBS > JBS > DMS), peak viscosity (JBS > BNS > DMS > AYBS), setback viscosity (AYBS > BNS > JBS > DMS) and breakdown viscosity (AYBS > DMS > BNS > JBS). However, annealing increased pasting temperature (BNS > JBS > DMS > AYBS), water (JBS>DMS>BNS>AYBS) and oil (JBS > DMS > BNS > AYBS) absorption capacities.