African yam bean (Sphenostylis stenocarpa (Hochst ex. A. Rich.) Harms) is an annual legume with the capacity to produce bean seeds in a pod and produce tubers with varying seed patterns and colors. It is suggested to have the potential to significantly boost food security in sub-Saharan Africa due to its considerable nutritional qualities but still yet underutilized. Many farmers show limited interest in its production owing to limited knowledge of its nutritional profile, income generation capacity for small-holder farmers’, processing, and other related utilization concerns. This study evaluated the proximate and antinutrient composition of processed and unprocessed seeds of African yam bean (Sphenostylis stenocarpa (Hochst ex. A. Rich.) Harms.). Seeds were harvested from the experimental research field consisting of 50 accessions at the International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria. They were divided into two portions; the first was processed by oven drying at 60°C for 24 hours and the second was left raw. There were significant differences (P<0.05) in the levels of proximate and antinutrient in the forms in which the samples were analyzed. TSs104 had the highest protein content of 25.08%, while the lowest was TSs68 (20.50%). However, in the unprocessed seed, protein content ranged between 24.93% (TSs38) and 19.13% (TSs11). Both processed and unprocessed seeds had high carbohydrate contents. In processed seeds, TSs9 (62.93%) had the highest percentage and TSs1 (29.64%) recorded the lowest. In unprocessed seed, the percentage ranged between 67.36% (TSs4) and 54.23% (TSs38). The observed variation may suggest possible suitability of seed for various end-use products and targeted breeding programs for crop improvements. In sub-Saharan Africa, this lesser-known legume could be adapted as a promising food crop in combating protein-energy malnutrition.

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Many people in sub-Saharan Africa suffer from protein malnutrition; this results in negative health and economic impacts. Winged bean (Psophocarpus tetragonolobus (L.) DC.) is a tropical underutilized legume with beneficial nutritional characteristics such as high protein content, which may help to alleviate these problems. The proximate composition (fat, moisture content, crude protein, ash, and carbohydrate) and antinutrient (tannin and phytate) level of winged bean seeds and tubers were determined using 50 accessions. In the processed seeds, accession Tpt17 had the highest protein content (40.30%) and Tpt48 the lowest (34.18%). In the unprocessed seeds, Tpt17 also recorded the highest crude protein (31.13%) with Tpt125 having the lowest (28.43%). In the tubers, protein content ranged from 19.07% (Tpt42) to 12.26% (Tpt10). The moisture content in the processed seeds ranged from 8.51% (Tpt42) to 6.72% (Tpt6); in the unprocessed seeds, it was between 8.53% (Tpt53) and 3.76% (Tpt14). In the processed seeds, the values of ash ranged from 4.93% (Tpt126) to 4.45% (Tpt15-4); in the unprocessed seeds, it ranged from 4.98% (Tpt17) to 4.55% (Tpt125). In the processed seeds, the fat content ranged from 18.91% (Tpt51) to 14.09% (Tp43) while in the unprocessed seeds, the values ranged from 19.01% (Tpt15) to 13.87% (Tpt3-B). The crude fiber in the processed samples ranged from 13.82% (Tpt6) to 10.40% (Tpt125) while in the unprocessed seeds, it ranged from 7.29% in Tpt51 to 4.83% in Tpt11. Carbohydrate content in the processed seeds ranged from 26.30% (Tpt3-B) to 20.94% (Tpt125) and 39.76% in Tpt3-B to 34.53% in Tpt18 in the unprocessed seeds. The tannin and phytate contents showed remarkably significant differences. In the tubers harvested, significant variation was observed in the parameters evaluated. Winged bean flour could be formulated into various meals for children and adults to reduce malnutrition in sub-Saharan Africa.