Abstract

This study was designed to investigate the suitable proportions of cowpea that can be used to improve the nutrient content of sorghum and also to ascertain the effect of fermentation on the sample blends. The raw and fermented sample blends were analyzed for microbial load, proximate composition, mineral and anti-nutrient contents. The microorganisms isolated were Staphylococcus aureus, Bacillus cereus, B. polymyxa, B. licheniformis, Lactobacillus fermentum, L. acidiophilus, L. plantarum Streptococcus lactis, Aspergillusf lavus, A. fumigatus, A. niger, Mucor mucedo and Rhizopus nigricans. Moisture content of unfermented sample blends ranged between 0.75 and 1.07% while that of fermented blends ranged between 26.96 and 42.65% respectively. Unsupplemented cowpea recorded the highest level of ash content before and after fermentation but crude protein increased after fermentation. Unsuplemented cowpea recorded the highest level of protein content. Cowpea: sorghum (7:3) also had a significant amount of protein when compared with sorghum: cowpea (8:2). Carbohydrate content reduced after fermentation while anti-nutrient content reduced significantly after fermentation process. There was significant increase in protein content of sorghum supplemented with cowpea, and a drastic reduction in the anti-nutrient content of all the fermented sample blends. Therefore, it can be concluded that sorghum supplemented with cowpea, then fermented for 72 h could be recommended for improving the protein quality of sorghum.

Key words: Sorghum, fermentation, anti-nutrient, Lactobacillus fermentum, cowpea.