Title: Wheat flour exposed to ethanol yields dough with unexpected properties Authors
|Hurkman Ii, William|
Submitted to: Journal of Cereal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 29, 2011
Publication Date: August 31, 2011
Repository URL: http://cerealchemistry.aaccnet.org/action/doSearch?action=runSearch&type=advanced&result=true&prevSearch=%2Bauthorsfield%3A(Robertson%2C+George+Harcourt)
Citation: Robertson, G.H., Hurkman Ii, W.J., Cao, T., Gregorski, K.S., Tanaka, C.K., Glenn, G.M., Orts, W.J. 2011. Wheat flour exposed to ethanol yields dough with unexpected properties. Journal of Cereal Science. DOI:10.1094/CCHEM-03-11-0041. Interpretive Summary: New dough properties based on wheat flour may be effected by breeding, genetic manipulation, formulation, and by physicochemical modifications. We have discovered that a mild treatment of flour with ethanol irreversibly alters how wheat develops into a dough and produces responses by conventional technology instruments that suggest improved dough properties. This material change occurs without compositional change as determined by robust analytical tools. The technique provides insight into wheat protein interactions and may be the basis for a dough improvement technology.
Technical Abstract: Wheat flour may be exposed to ethanol solutions in such a way as to alter the subsequent transformation of the flour into dough. Here, a number of types of wheat flour were exposed to small amounts of ethanol solutions so as to be "wetted" but without the appearance of a separate liquid phase. The wet sample was dried in air. Dough was formed from the treated flour and rheological parameters assessed including time to peak strength (Mixograph and Farinograph) and gluten index (Glutomatic). Untreated and treated flour samples and dough samples were assayed using 1D SDS PAGE (reducing and unreducing conditions), capillary zone electrophoresis applied to 70% leachates with and without sonication, and differential scanning calorimetry. Both gluten index and time-to-peak measurements increased as a result of the treatment and the increase was greater for flour or enriched vital gluten with initially low gluten index than for flour with relatively high initial index. Endosperm fragmentation in milling was improved by the treatment. Thermal transitions were at slightly lower temperatures indicating a less ordered structure. No compositional differences were evident for robust analytical methods. CZE of leached samples (no sonication) revealed lower amounts of proteins following treatment. Conformational changes and new secondary interactions, therefore appear to be responsible for the effect.