Quality and Sensory Evaluation of Bread Made from Wholewheat Flour Partially Substituted With Sweet Potatoes

This study evaluated the quality parameters of bread made from wholewheat flour partially substituted with sweet potato flour at varying ratios (5–25%). The bread was produced using standard recipe and analysed using standard methods. Data were recorded in triplicates and subjected to ANOVA on SPSS version 27.0 with means separated using Duncan Multiple Range Test (DMRT). The results showed that functional properties improved with increasing sweet potato content: bulk density ranged from 0.66–0.71 g/cm³, water absorption capacity from 2.94–3.31 cm³/g, and oil absorption capacity from 1.79–2.56 cm³/g. Swelling capacity rose significantly from 3.04 g/g (100% wholewheat) to 3.98 g/g at 20% substitution. Pasting properties peaked at 25% substitution, with the highest peak viscosity (2527.18 RVU) and final viscosity (2665.63 RVU), indicating enhanced gelatinization potential. Proximate composition revealed increasing moisture (26.02–29.65%), ash (3.72–4.89%), and crude fibre (1.07–2.21%) with substitution, while protein and carbohydrate content declined from 19.56% to 14.31% and 41.25% to 28.38%, respectively. Fat content rose from 12.44% to 15.58%. Antioxidant-rich sweet potato flour enhanced mineral content, notably calcium (4.17–4.58 mg/100 g) and magnesium (2.52–3.39 mg/100 g). Microbial analysis indicated relatively low spoilage through day 3, with 25% substitution showing the lowest bacterial count (1.0×10⁵ cfu/g). Sensory evaluation showed that consumer acceptability declined with higher substitution. Bread with up to 10% sweet potato maintained acceptable sensory scores (overall acceptability: 6.98), while 25% substitution was least favoured (5.90). The study concluded that, partial substitution of wholewheat flour with sweet potato flour enhanced functional, nutritional, and some pasting characteristics with the optimal balance between nutritional benefits and sensory appeal achieved at 10% substitution, suggesting this ratio as the most suitable formulation for fortified bread production with improved health benefits and consumer acceptability.