Impact of wheat bran physical properties and chemical composition on whole grain flour mixing and baking properties

Abstract

Wheat bran can have diverse chemical composition and physical properties. The objective of this study was to determine the associations among physical and chemical properties of bran and the mixing and baking properties of whole wheat flour. Eighty samples of bran were milled into fine (463 μm) and coarse (783 μm) particle size groups and analyzed for water retention capacity, protein, ash, lipoxygenase activity, antioxidant activity, sulfhydryl groups, and extractable phenolics. Brans were mixed with a single refined flour to make reconstituted whole wheat flour and analyzed for mixing and baking quality. Fine particle size samples had larger bread loaf volume, and softer bread texture compared to the coarse samples. Bran protein and extractable phenolics showed positive correlations with dough strength (p < 0.01) and development time (p < 0.01), respectively. Bran ash was positively correlated with dough strength (p = 0.004). Water retention capacity (WRC) of bran was significantly correlated with dough development time (p = 0.002), bread volume (p = 0.002) and initial hardness (p = 0.007) and firmness (p = 0.028). Overall, this study suggested a strong relationship between bran protein, ash, extractable phenolics, and water retention capacity and whole wheat flour functional properties.