Nutritional and Pasting Properties of Enriched High-Quality Bread from Sweet-Potato Flour Spiced with Ginger
Authors: Omolola M. Omosebi, Samuel S. Sobowale, Joshua O. Fiola and Jesukorede C. AlukoThe rising demand for functional and nutritionally enhanced baked products has driven increased research into composite flour technology. This study developed and evaluated high-quality composite flour and bread from sweet potato-wheat flour incorporated with ginger powder, aiming to enhance the nutritional, sensory, and physicochemical properties. Composite flours were prepared by substituting sweet potato flour at 0%, 5%, 10%, 15%, and 30% (WH100, WH95, WH90, WH85, and WH70, respectively) and incorporating 1% ginger powder. The flours were analysed for pasting properties using the Rapid Visco Analyzer, while the bread samples were analysed for proximate composition, pH, and sensory attributes using standard methods. Result showed that protein content was highest in WH100 (15.45%) but declined with an increase in sweet potato inclusion, whereas fibre content improved, reaching 1.27% in WH70. Carbohydrate content also increased, with WH70 recording the highest value (73.13%). pH values ranged from 6.61 in WH70 to 7.23 in WH90, indicating reduced acidity at moderate substitution levels. Pasting results showed that peak viscosity increased with sweet potato addition, highest in WH70 (1564 RVU), although higher substitution also led to greater breakdown viscosity, suggesting reduced paste stability. Sensory evaluation revealed that WH70 achieved the highest overall acceptability among composite breads, closely aligning with the control WH 100, while WH95–WH85 scored lower. These findings suggest that WH70, with sweet potato flour at 30% substitution, in combination with 1% ginger powder, can be incorporated into wheat-based bread to enhance fibre content and functional properties while maintaining desirable sensory quality.