Improvement by oxidising agents of the baking performance of pure and composite flours from nigerian‐grown wheats (Lee X and Inia 66)

Abstract

AbstractThe feasibility of improving the bread‐baking performance of two varieties of Nigerian‐grown wheat (Lee X and Inia 66) in pure and composite flour, using the oxidising agents potassium bromate and ascorbic acid was studied. Composite flour was prepared by mixing pre‐cooked bambara bean (Voandzeia subterranean) flour at levels between 0 and 50% with each of commercial (control), Lee X and Inia 66 wheat flour. Physical and sensory evaluations showed that the performance of straight Lee X and Inia 66 flours was inferior to that of the commercial flour. The commercial flour showed better tolerance to blending with bambara flour, producing acceptable loaves at up to 20% substitution with bean flour; Lee X and Inia 66 could not tolerate blending beyond 15% and 5% levels, respectively. Physical properties and baking performance of the Lee X and Inia 66 flours were improved by treatment with various levels of the oxidising agents KBrO3, ascorbic acid and KBrO3/ascorbic acid combinations. Lee X flour was more responsive to the treatments than Inia 66. Concentrations of 25 mg kg−1 KBrO3 and 80 mg kg−1 ascorbic acid singly were found to improve Lee X flours adequately, but a combination of the two agents at a level of 25/60 mg kg−1 KBrO3/ascorbic acid was optimal. When treated with the optimal level of improver combination, Lee X flour performed as well as the commercial flour; and treated Lee X composite flours containing up to 30% pre‐cooked bambara flour were found to produce loaves not significantly different from 100% commercial wheat bread (P≤0.05).