Effect of Purple-Colored Wheat Bran Addition on Quality and Antioxidant Property of Bread and Optimization of Bread-Making Conditions

Abstract

Purple-colored wheat bran was blended with flour at different ratios. The dough mixing characteristics of the flour–bran blends and quality characteristics and antioxidant activity of the bread prepared with the blends were investigated. Additionally, response surface methodology (RSM) was used to optimize the formula and processing conditions for the bread prepared with the blend at 30% bran. Solvent retention capacity (SRC), as a quality characteristic of the blends, showed that water absorption and damaged starch contribution increased proportionally as the bran blending ratio increased. Dough mixing patterns of blends determined by a mixograph exhibited deteriorated gluten strength by increasing the bran blending ratio. The total phenolic and anthocyanin contents and antioxidant activity (ABTS and DPPH radical scavenging activity) of the bread increased proportionally as the bran blending ratio increased. RSM analysis revealed that the best-fitted model for the results was a quadratic polynomial model with regression coefficient values close to or more than 0.900 for all responses. Optimized conditions were 68.1 g water, 4.0 min mixing time, and 67.3 min fermentation time. Overall, purple-colored wheat bran was successfully applied to produce bread with healthy functional properties by controlling water and mixing time.

Keywords

• purple-colored wheat bran
• flour–bran blend
• bread
• antioxidant activity
• response surface methodology
• optimization