Location: Corn, Soybean and Wheat Quality ResearchTitle: Qualitative effect of added gluten on dough properties and quality of Chinese steamed bread
|MA, FENGYUN - The Ohio State University|
Submitted to: Cereal Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/5/2017
Publication Date: 9/1/2017
Publication URL: https://handle.nal.usda.gov/10113/5806760
Citation: Ma, F., Baik, B.-K. 2017. Qualitative effect of added gluten on dough properties and quality of Chinese steamed bread. Cereal Chemistry. 94(5): 827-833.
Interpretive Summary: Both protein content and gluten protein strength are known to significantly affect the Chinese steamed bread (CSB)-making quality of wheat flour, while previous reports show conflicting results on the nature of their relationships (positive vs. negative) with CSB quality attributes. Discrepancies among the previous studies may result from using wheat flours of variable protein content, and neglecting to control other factors in the determination of the role of protein content or protein strength when making CSB. We attempted to determine the influence of gluten protein strength on dough properties and CSB quality under a controlled protein content to avoid its interference. Glutens of different strengths isolated from 15 soft red winter (SRW) wheat varieties were incorporated into a base wheat flour to prepare wheat flour blends of similar protein content, but different in gluten strength, and to determine the significance of gluten protein strength on CSB quality independent of protein content. We found that CSB made from flours containing added strong glutens exhibited a smoother surface, better crumb structure and higher total score than that made from flours containing added weak glutens. In addition, significantly positive relationships of protein strength with CSB specific volume and stress relaxation were observed with the gluten-added flours. A quantitative increase in gluten protein resulted in improved dough mixing properties with little effect on dough extensibility, and increased the scores of CSB specific volume and crumb structure without affecting surface smoothness, stress relaxation and total score of CSB. Substantial variations in the maximum force for extension, dough extensibility and CSB total score of the gluten-added flours resulted from differences in gluten protein strength, indicating that protein strength had a considerable effect on those parameters. Our results indicate that consideration of gluten protein strength in the evaluation and selection of wheat varieties is necessary for the production of high quality CSB. It is evident that SRW wheat varieties producing grain of relatively high protein content and high gluten strength would be suitable for the production of CSB.
Technical Abstract: Glutens isolated from fifteen soft red winter (SRW) wheat flours were added into a SRW wheat flour to obtain protein levels of 9.6% and 11.3% for determination of the qualitative effect of gluten protein on the dough properties and quality of northern-style Chinese steamed bread (CSB). Sodium dodecyl sulfate sedimentation (SDSS) volume of flour used for gluten isolation exhibited positive relationships with mixograph absorption, midline peak time (MPT) and midline peak value (MPV) of the gluten-added flours and with surface smoothness, crumb structure and total score of CSB prepared from the gluten-added flours regardless of protein content. Positive correlations were also observed between SDSS volume of the source flour of gluten and specific volume and stress relaxation score of CSB prepared from the gluten-added flours of 11.3% protein. The increase in protein content by gluten addition improved mixograph absorption, MPT and MPV with slight effect on resistance breakdown, dough maximum force for extension and extensibility, and increased CSB specific volume and crumb structure score without affecting surface smoothness, stress relaxation and total score. Mixograph parameters exhibited significant relationships with CSB total score, indicating that they could be effective predictors of the CSB-making quality of flours.