Nutrient improvement of yam pottage meal using African yam bean (Sphenostylis stenocarpa) flour

Abstract

Background: African Yam Bean (Sphenostylis stenocarpa) is one of the under-utilized legumes in Nigeria. It is an inexpensive, nutrient-dense source of protein, and also an excellent source of essential minerals and other phytochemicals.

Objective: To assess the nutrient improvement capacity (especially protein) of African yam bean on yam pottage meal.

Materials and Methods: African yam bean (AYB) seeds were purchased from Orba International market, Udenu LGA of Enugu State, Nigeria. About 300g of the seeds were weighed, washed in distilled water, drained and roasted in an aluminium roasting bowl (Agbada) until cracking set in. The roasted seeds were milled whole into fine flour. The resulting flour was added to yam pottage meal (400g each wwb) as the only protein source, in the following proportions: 100g (AYB ), 80g (AYB ), 60g (AYB) and 0g (YP), control sample. The meals were subjected to proximate and micronutrient 1 2 3 analyses. The sensory qualities as well as acceptability were also evaluated. The data obtained were subjected to statistical analysis.

Results: Crude protein contents of the AYB-incorporated pottage meals increased significantly (p≥0.05) from 3.19±0.01% in the YP (control) to 6.67 ±0.12% (AYB ). Significant decreases (p≥0.05) were observed in crude fiber, from 0.82±0.10% (YP) 1 to 0.28 ±0.02%(AYB );ash increased from 3.28±0.02%(YP) to 3.65±0.01% (AYB ) ;fat decreased from 6.26 ±0.06%(YP) to 1 10.83±0.03%(AYB ). Results on calcium, zinc, iron and β-carotene indicated significant (p≥0.05) increases from 1 2.48±0.12mg 100g-1 (YP) to 9.45±0.16mg 100g-1 (AYB ); from 0.14±0.03mg 100g-1 (YP) to 0.25±0.02mg 100g-1 (AYB ); from 3 1 0.67±0.02mg 100g-1(YP) to 2.90±0.05mg 100g-1(AYB ); 9and from 168.48μgRE (YP) to195.04 μgRE (AYB ), but a significant 1 2 decrease in (AYB ),155.54 μgRE, respectively. Sensory evaluation result revealed that AYB was the most generally 3 3 acceptable sample.

Conclusion: African yam bean can be used to improve the protein, reduce the fat and also increase the calcium, zinc, iron and β-carotene contents of yam pottage meal which is principally a carbohydrate food.

Keywords: Sphenostylis stenocarpa, nutrient improvement, legume