Physicochemical composition and glycemic index of whole grain bread produced from composite flours of quality protein maize and wheat
C. T. Akanbi, A. V. Ikujenlola*
Department of Food Science and Technology, Obafemi Awolowo University, Ile-Ife, Nigeria
original scientific paper
This study entails quality assessment of whole grain bread produced from composite flours of quality protein maize and wheat. Quality protein maize and wheat were processed into flours and mixed at various ratios for bread production. The proximate compositions, physical properties, glycemic response, functional and sensory properties of the samples were evaluated using standard methods. The result showed no significant difference (p<0.05) in the proximate composition parameters of the bread samples. The loaf height(2.50-3.95 cm), volume (291.00-415.00 cm3) and specific volume(1.72-2.42 cm3/g) decreased significantly with increasing level of quality protein maize, however, loaf length was not affected by the substitution of quality protein maize. The result of the functional properties showed that final viscosity, water absorption and swelling capacity increased with increasing level of quality protein maize. The result of the glycemic response showed that the inclusion of quality protein maize resulted in decline in the blood glucose content (glycemic index) of the products. The bread samples were generally acceptable however; bread with 100% wheat was the most preferred. The result of the sensory properties showed that there was significant difference (p<0.05) in the texture and taste of 100% wheat bread and the other samples. The study concluded that substitution of quality protein maize with wheat produced acceptable whole grain loaves that have positive effect on the reduction of blood glucose level.
Keywords: quality protein maize, bread volume, dough expansion, bulk density, glycemic response