Evaluation of the nutritional composition ofthe seeds of some selected African yam bean (Sphenostylis stenocarpa Hochst Ex. A. Rich (Harms)) accessions

Abstract

African yam bean (AYB) is an important but neglected and underutilized crop producing edible seeds and tubers. The poor awareness of the nutritional values of AYB constitutes one of the major problems limiting its utilization. This study was, therefore, carried out to determine the nutritional potentials of five accessions of African yam bean (TSs 125, TSs 116, TSs 86, TSs 69 and TSs 60) by analyzing their proximate composition and micronutrients (Iron (Fe), Zinc (Zn) and Selenium (Se)). The experiment was laid out in completely randomized design (CRD) with three replications. The results obtained showed significant (p < 0.05) variations in the proximate composition of the AYB accession. The crude protein was in the range of 21.84-23.41 %, crude fat 3.40-3.86 %, fibre 6.17- 6.76 %, carbohydrate 52.8-54.48 %, dry matter 90.42 - 90.6 %, ash 4.22 - 4.35 %, and moisture 9.4 - 9.58 %.The Se concentration varied from 312 mg/100 g in TSs 116 to 58 mg/100 g in TSs 60 while Fe ranged between 10.40 mg/100g in TSs 60 and 6.07mg/100gin TSs 86. Zinc varied between 8.83 mg/100g in TSs116 and 6.37 mg/100 g in TSs 69.TSs 116 was best accession in terms of crude protein, dry matter, ash, selenium and zinc, while TSs 60 was best in terms of iron. The study revealed AYB seeds as a food crop rich in protein, carbohydrate, fibre, selenium, iron and zinc. The genotypic variability can be exploited in developing African yam bean varieties with better qualities in terms of nutrient density.

Keywords: Neglected, underutilized, nutrient-dense, micronutrient and protein