Influences of hydrothermal and pressure treatments of wheat bran on the quality and sensory attributes of whole wheat Chinese steamed bread and pancakes

Authors: MA, FENGYUN - THE OHIO STATE UNIVERSITY; LEE, YU YOUNG - KOREAN RURAL DEVELOPMENT ADMINISTRATION; Park, Eunhee; Luo, Yaguang - Sunny; Delwiche, Stephen - Steve; Baik, Byung-Kee

Submitted to: Journal of Cereal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/13/2021
Publication Date: 10/18/2021
Citation: Ma, F., Lee, Y., Park, E., Luo, Y., Delwiche, S.R., Baik, B.V. 2021. Influences of hydrothermal and pressure treatments of wheat bran on the quality and sensory attributes of whole wheat Chinese steamed bread and pancakes. Journal of Cereal Science. 102. Article 103356. https://doi.org/10.1016/j.jcs.2021.103356.
DOI: https://doi.org/10.1016/j.jcs.2021.103356

Interpretive Summary: When compared to refined flour foods, whole grain wheat foods deliver fewer calories and more dietary fiber and micronutrients, and subsequently impart numerous health benefits to the consumer, however, whole wheat foods are inferior in quality and sensory acceptance, largely because of the negative effects of bran particles in the whole wheat meal. Pre-treatments of bran before being blended with refined flour for the preparation of whole wheat meal and identification of the appropriate processing methods for making whole wheat products are believed to be effective approaches for mitigating the negative influences of bran on product quality. We have explored various hydro, thermal and pressure treatments of bran for the improvement of functional properties and the quality of dough- and batter-based products (steamed bread and pancakes, respectively), and have determined the effects of pre-hydration and delayed incorporation of bran into dough on steamed bread quality.The incorporation of hydrated (instead of dry) wheat bran after the full gluten development of the dough of the ref ined flour and gluten blend effectively mitigated the detrimental influences of bran on steamed bread quality attributes, as was made evident by its positive effects on specific volume, surface smoothness and crumb structure. The extrusion treatment was identified to be a desirable pre-treatment of bran for making whole wheat steamed bread with a significant improvement in the scores of crumb structure and stress relaxation and springiness. Autoclaving of bran was effective for making whole wheat pancakes with a significant improvement in the moistness of crumb. These results provide food manufacturers with guidance for selecting appropriate pre-treatments of bran and processing methods for the improvement of the quality attributes of whole wheat dough-based and batter-based products.

Technical Abstract: This study investigated the effects of wheat bran pre-treatments by autoclaving, roasting, jet cooking, extrusion, puffing and high-temperature-high-pressure (HTHP) cooking on the properties of whole wheat meal (WWM) and the sensory attributes of Chinese steamed bread (CSB) and pancakes prepared from blends of refined flours and brans. All the pre-treatments of bran imparted negative influences on the gluten index of WWMs compared to untreated bran. Pre-hydration of bran and its incorporation into the fully developed dough of refined flour significantly improved the specific volume, surface smoothness and crumb structure of CSB. Autoclaving, roasting, jet cooking and puffing of bran resulted in no apparent positive effects on CSB sensory attributes. HTHP cooking significantly increased CSB specific volume, but negatively affected the flavor, texture and overall quality score. Extrusion of bran improved CSB crumb structure, stress relaxation score and springiness. No apparent improvement in the sensory attributes was observed in pancakes with roasted, jet-cooked, extruded and puffed brans. The autoclaved bran produced pancakes of higher crumb moistness than untreated bran. The results suggest that extrusion and autoclaving of bran prior to being blended with refined flour would be effective ways to improve the quality of whole wheat CSB and pancakes, respectively.