Quality Evaluation of Composite Bread Produced from Wheat, Maize and Orange Fleshed Sweet Potato Flours

摘要

The research was carried out to evaluate the effect of addition of yellow maize (YM) and orange fleshed sweet potato (OFSP) flours on the quality of wheat bread. Maize and sweet potato were processed into flour and mixed with wheat flour for bread production. Five samples of bread were produced and denoted as Samples A to E. Sample A was the control with 100% wheat flour, while Sample B to E had maize and sweet potato flours added in an increasing order of 5 to 20%. The physical properties of the bread loaves were evaluated and the result decreased significantly with increasing levels of yellow maize and orange fleshed sweet potato flours. The loaf volume varied from 340 to 182 cm3 and the bread specific volume ranged from 1.35 to 0.99 cm3/g. The result of the proximate composition showed that moisture and protein contents decreased significantly (p<0.05) with increase in yellow maize and orange fleshed potato flours varying from 34.97 to 29.97% and 13.12 to 7.67% respectively. The fat, crude fibre, ash and carbohydrate contents of the bread samples generally increased significantly (p<0.05) with increase in maize and orange fleshed potato flours. The result of the mineral content revealed that β-carotene and calcium increased significantly with increased levels of maize and sweet potato. The values of magnesium iron and phosphorus in the bread samples had no definite trend. The result of the sensory properties showed that there was significant difference in the texture and taste of 100% wheat bread and the other samples. The 100% wheat bread recorded the highest scores in all the parameters evaluated however all the other samples were well accepted. There was a decrease in the values of overall acceptability, appearance and flavor of the bread samples with increasing levels of maize and sweet potato flours but the decrease was not significantly different.