Use of Seed Sprouting in Modification of Food Nutrients and Pasting Profile of Tropical Legume Flours

Abstract

The study investigates the effect of seed sprouting on minerals, anti nutrients and pasting characteristics of flours produced from some tropical legume seeds. Samples were collected from cowpea (Vigna ungulculata); red kidney beans (Phaseolus vulgaris); and Pigeon pea (Cajanus cajan) and each sample was divided into two portions. A portion was sprouted while the other portion served as the control. The flours from sprouted and non-sprouted seeds were analyzed for the minerals, anti nutritional and pasting properties. The samples were found to differ significantly (p < 0.05) in the minerals, anti nutritional composition and pasting properties of the flours. Sprouting increased the mineral contents of the flours generally the calcium content of non-sprouted red kidney beans (13.8 mg/100 g) increased to 16.1 mg/100 g in the sprouted flour. The haemagglutinin decreased from 40.6 HU/mg in non sprouted red kidney to 6.4 HU/mg in the sprouted. The final viscosity of the non sprouted flours were higher than those of the sprouted, with non sprouted cowpea scoring the highest, 272 RVU, while sprouted red kidney beans had the least, 109.06 RVU, which implies that sprouting caused a reduction in the gel strength and elasticity of the samples. Seed sprouting effectively increased the mineral nutrients and lowered the anti nutrients, but produced steamed paste with poor gel strength.

Keywords: Legume seeds, seed sprouting, calcium, haemaglutenin, final viscosity.