Effect of Added Fermented African Yam Bean Flour on Nutrient Composition. Physical and Sensory Properties of Wheat Bread:- Chidi Faith

ABSTRACT

 Blends of wheat flour (wf) and African Yam Bean Water- Extractable Proteins (A YBWEP) were processed into bread in the following ratios; I 00:0 (sample A) 90: I Oa (sample B), 90:1 Ob (sample C). 70:30a (sample D) 70:30b (sample E). The proximate composition, Antinutrient content. functional. physical and sensory properties of the bread samples from the composite flour blends were determined in this study and the effect of substituting fermented African yam bean flour on the properties (anti-nutrient. physical. functional and sensory) of the bread was also investigated. Fermentation done at different time intervals significantly (p<0.05) increased the levels of crude protein with a significant reduction in the anti-nutrient content (Tannin. Phytate) of the flour. Breads produced from the resultant blends of the African yam bean fermented at different time intervals (24hrs & 48hrs) were significantly higher (p<0.05) in crude protein ranging from (13:14- 16.98%) than the control (100:0) which has the least value (13.14%). The carbohydrate content decreased from 58.78% with addition of fermented African yam bean flour to 54.83% following 30% substitution. The energy value of the bread samples prepared from whole wheat flour and the blends wheat flour and fermented African yam bean flour were significantly different (P<0.05). The energy value of bread samples decreased with an in increase in the proportion of fermented African yam bean flour blend from 388.97 - 385. 12kcal/g with sample E (70:30b) having the least value (385.12kcal/g) and sample D (70:30a) with the highest value (388.97kcal/g). The highest specific volume (5.47cm3/g) was observed in the bread samples prepared from the control (Sample A) ( 100:0) while sample B (90: I Oa) blends had the lowest specific volume (5.27cm3/g). There was no significant difference (p<0.05) in the bulk density of the bread. The water absorption capacity (WAC) of the flour increased after fermentation. The substitution of the wheat flour increased the water absorption capacity (WAC) of the bread. The general acceptability of the bread decreased with higher ratios of the fermented African yam bean flour inclusion in the blend. The sensory acceptability scores shows the best Fermented African Yam Bean Flour substitution level for making bread was 90:1 Ob. The study demonstrated that fermented African yam bean flour could be explored for the preparation of wheat based bread with reduced gluten levels. As a practical application, the study can assist in increasing the utilization of some neglected leguminous crops as well as addressing the challenges of malnutrition. prevalent in developing countries.