Quality Assessment of sorghum couscous made from the hulled grains of the same crop with different sizes

Abstract

Aims: This study aims to estimate the effects of grain size of white sorghum bicolor L. and the decortication process of grains on the production, physicochemical properties, cooking properties, color and sensory quality of couscous. 

Methods: The white sorghum bicolor L. grains from the same crop were devised into three divisions depending on the grain size. The grains were decorticated and milled to agglomerate the extracted sorghum semolina, yielding three samples of the homemade couscous. The commercial ready-made durum semolina was used to prepare durum wheat couscous as a control. The couscous samples and control were evaluated for their proximate composition (protein content, starch content, and dietary fiber content), cooking properties, color indices, and sensory attributes.

Results: Three homemade couscous samples of sorghum were produced in the best yield of 88.42-90.27% comparing to control yield 82.30 %, with high and varied content of protein, starch and dietary fiber those were significantly different with grain size. Protein, starch and dietary fiber content in sorghum couscous samples were ranged from 11.45-14.67%, 60.18-75.51% and 2.61-10.55%, respectively. Sorghum couscous samples have darker color than control. Sorghum couscous A and sorghum couscous B have best cooking quality with except large cooking time, and moderate overall acceptability of appearance and color. Sorghum couscous C had poor cooking loss and was poorly scored for sensory attributes.

Conclusions: The findings in this study confirm the significant effects of grain size on the agglomeration process and sorghum couscous quality. Decortication of grains was associated with the yield, size distribution and color of sorghum couscous.

Keywords: White sorghum bicolor, size, Couscous, Physicochemical properties, Nutrient, Food quality.