Authors : Ibrahim Doris Gideon; Usman Ojali Grace

Volume/Issue : Volume 11 - 2026, Issue 5 - May

Google Scholar : https://tinyurl.com/59n7af34

Scribd : https://tinyurl.com/mumxacrp

DOI : https://doi.org/10.38124/ijisrt/26May1003

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Abstract : This study is aimed at isolating and evaluating proteins from Bambara groundnut (BGN), cowpea (CP), pigeon pea (PP), African yam bean (AYB) and soybean (SB) seeds using a 1 x 5 factorial in a completely randomized design (CRD). Each legume was individually soaked for ten hours after initial wet cleaning to remove debris and unwanted matter. Soaked grains were rewashed and milled into a uniform paste and thereafter subjected to protein extraction using standard methods to obtain dried products, where Bambara groundnut had the highest percentage of protein yield. Physiochemical analysis showed that pH and colour of isolated showed a maximum of 4.40 (cowpea) and 7.67 (AYB), while acidity, crude protein, crude fat and moisture content showed 2.52 (AYB), 88.90 (SB), 8.45 (SB), and 6.55 (BGN) respectively all in percentage. Bulk density and emulsion capacity results showed maximum of 0.99gram per milliliters (PP), 47.34 (SB). Viscosity, swelling capacity and water absorption capacity showed a maximum of 30.23Newton second per meter (CP), 44.46 percent (PP) and 10.55gram per milliliters (PP) respectively. Solubility test revealed all isolates were soluble in water and 0.1N hydrochloric acid but were insoluble in chloroform. Amino acid profile of the isolates showed relatively high values for leucine 8.33 (SB) - 7.62 gram per100gram (AYB); aspartic acid 8.62 (CP) - 9.56 gram per100gram (PP); glutamic acid 13.03 (CP) - 14.34 gram per100gram (SB) and arginine 6.55 (CP) - 7.32 gram per100gram (PP) respectively. A sensory result conducted for garri enriched with the isolate indicated that the panelists scored all samples above average, thus were favourably disposed to the samples. These results will support introduction and commercialization of these isolates for more impact in terms of nutrient availability.

Keywords : Protein Isolates, Physico-Chemical, Indigenous and Legumes.

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