Effects of bran pre-hydration on functional characteristics and bread baking quality of bran and flour blends

Authors: PARK, EUN YOUNG - Washington State University; FUERST, E. - Washington State University; Baik, Byung-Kee

Submitted to: Cereal Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/11/2017
Publication Date: 9/1/2017
Publication URL: https://handle.nal.usda.gov/10113/5806745
Citation: Park, E., Fuerst, E.P., Baik, B.-K. 2017. Effects of bran pre-hydration on functional characteristics and bread baking quality of bran and flour blends. Cereal Chemistry. 94(5):834-839.

Interpretive Summary: Whole grain wheat foods present numerous nutritional and health benefits to consumers, but tend to be inferior in appearance, texture and flavor (and thus in sensory acceptance) to refined flour food products. To increase the consumption of whole grains, it is necessary to enhance the product quality and sensory characteristics of whole grain wheat foods. Since bran contributes substantial amounts of healthful bioactive compounds including fiber, vitamins, minerals and phytochemicals, and at the same time causes the poor product quality and palatability of whole grain wheat foods, modification of bran functionality would be the logical and appropriate approach for improving the quality and taste of whole grain wheat foods. We found that pre-hydration of bran at 25'C increased dough water absorption, preventing water competition among dough constituents, and improved the loaf volume and decreased the firmness of bread prepared from refined flour and bran blends. The results demonstrate the advantages of bran pre-hydration in the production of whole grain wheat bread of improved product quality. This information would benefit the whole grain wheat milling and baking industries by providing an easily applicable way to boost the palatability of whole grain wheat bread, and eventually consumers by increasing the consumption of whole grain wheat bread.

Technical Abstract: The effect of bran pre-hydration on the composition and bread baking quality was determined using bran and flour of two wheat varieties. Bran was hydrated in sodium acetate buffer (50 mM, pH 5.3) to 50% moisture at 25 or 55°C for 1.5 or 12 h. The soluble sugar content in bran increased with pre-hydration. Decreases in phytate and soluble fiber were observed in pre-hydrated bran, but insoluble fiber was not affected by pre-hydration. Likewise, free phenolic content decreased and there was little change in the content of bound phenolics in pre-hydrated bran. The compositional changes were greater in the bran pre-hydrated at 55°C than at 25°C, and for 12 h than for 1.5 h. A higher loaf volume of fresh bread and lower crumb firmness of bread stored for 10 days were observed in bread containing bran pre-hydrated at 25°C than in bread containing non-hydrated bran or bran pre-hydrated at 55°C. The pre-hydration of bran at 25°C before being incorporated into refined flour for dough mixing improves bread quality by altering bran compositional properties, allowing enough water to be absorbed by fibrous materials in the bran and preventing water competition among dough constituents.