Physical, chemical and sensory properties of bread from blends of wheat and lima bean flours

Abstract

The study was conducted to determine the physical, chemical, and sensory properties of bread produced from wheat and lima beans flour blends. The study adopted a 1 by 5 plus 1 factorial design; lima beans were processed into flour and used to substitute wheat flour in different proportions (0, 10, 20, 30, 40, and 50%). Bread produced from 100% wheat flour was used as control. The proximate result of the bread samples showed that substitution of wheat flour with lima bean flour significantly increased the protein, ash and the crude fiber content of the products with values ranging from 13.76-24.26%, 2.92-3.84%, and 5.42-6.00% respectively while a significant decrease was observed in the moisture, fat and carbohydrate content of the products with values ranging from 18.78-15.41%, 4.75-3.30%, and 54.37-47.19%, respectively. Increasing substitution level of wheat flour with lima beans flour increased all the functional parameters; water absorption capacity from 0.77-2.46 g/ml, oil absorption capacity 1.38-1.87 g/ml, swelling properties 1.07-1.98 g/cm3, bulk density 0.95-1.68 g/g and foam ability 2.07-2.67 mg. From the physical properties, it was observed that loaf weight increases with an increase in substitution levels but on the other hand, loaf volume and specific volume decreases significantly (P< 0.05) at increasing substitution levels from 150.24-173.98 g, 701.05-482.09 ml, and 4.67-2.77 cm3 respectively. The mean sensory score of the bread samples showed that all the composite bread samples were generally acceptable. However, sample substituted with 20% lima bean flour was best preferred having the highest score ratings by the panellist in all the sensory quality attributes evaluated.