Effect of sourdough fermentation on the physical properties and sensory characteristics of bread made from Wheat (Triticum aestivum), Orange-Fleshed Sweet Potato (Ipomoea batata L.) and Soybean (Glycine max L.) Composite Flour

Sourdough bread was prepared by fermentation of wheat flour, orange-fleshed sweet potato and soybean composite flour using strains of Lactobacillus plantarum and Saccharomyces cerevisiae. To evaluate the effect of sourdough fermentation on the physical properties and sensory characteristics of the sourdough bread, the product was analyzed for loaf weight, height, volume, texture; crack and crust colour then subjected to sensory evaluation. The results revealed that the sourdough loaf weight, height and volume were; 153.2g, 1.88cm and 218cm3 , while the control sample was 181.1g, 1.26cm and 216cm3 , respectively. There was no significant (p>0.05) difference in texture, crack and crust colour. Sensory characteristics showed appearance (6.75 and 6.0), taste (6.45 and 5.83), aroma (5.66 and 4.75), texture (6.44 and 5.33) and overall acceptability (6.33 and 5.25) of sourdough bread and the control sample respectively. Fermentation positively had impact on the physical properties and sensory characteristics of sourdough bread produced. Lactic acid bacteria strains have the ability to improve loaf weight, height, volume and sensory acceptability. Sourdough fermentation technology is recommended to improve dough quality without adding baker’s yeast.