Quality of Pan Bread as Affected by the incorporation of Sweet Potato Flour

Document Type : Original Article


I N THE present study, we investigate the effect of replacing wheat flour with sweet potato flour (SPF) on rheological, physicochemical and sensory properties of pan bread. Sweet potato flour was incorporated into wheat flour at three replacement ratios as10, 20 and 30%.The obtained results revealed that water absorption values ranged from (59.11) to (79.10%) with control pan bread and pan bread 3 (30% SPF) having the lowest and highest values, respectively. Pan bread 3 (30% SPF) represented the highest water absorption and degree of softening values as (79.10) and (110.15), respectively. The stability time values of the blends ranged from (4.00) to (12.00) min.The elasticity values ranged from 240 to 505 with WF and 30% represented the least elasticity in pan bread 3 (30% SPF) and highest elasticity in the control pan bread, while pan bread 3 (30%) had the lowest extensograph properties values. Pan bread 3 (30% SPF) had the highest weight value (195.26) comparing with the control pan bread which was (151.50) and lowest volume and specific volume contents as 368.90 and 1.87, respectively. Pan bread 1 (10% SPF) had the highest protein content (10.47) after control pan bread which was (10.86) while pan bread 3 (30% SPF) had the lowest protein content as (8.79). Whereas fat content increased significantly with pan bread 3 (30% SPF) being the highest fat content as (7.97) comparing with the control pan bread which was (6.58). Pan bread 3 (30% SPF) had the highest fiber content as (1.29). A significant change in fibers and fats content was found. There were no significant differences between NFE of pan bread samples which ranged between (97.19) and (79.95). The highest calcium, potassium and zinc contents found in pan bread 3 (30% SPF) as (45.26, 204.54 and 13.67), respectively, comparing with control pan bread which was (36.54, 189.51 and 13.25), respectively. Β-carotene ranged from (0.42 to 0.79) with pan bread 3 having the highest β-carotene content as (0.79). Pan bread 1 containing 10% sweet potato flour was equally acceptable and was significantly better than those with 0, 20 and 30% sweet potato flour as (5.00).By increasing sweet potato (Ipomoea batatas) flour levels, ash and crude fiber contents increased but decreased the level of protein. Keywords: Sweet potato flours, Pan bread, Rheological properties, Chemical composition.