Cereal Chem 65:198-201   |  VIEW ARTICLE

Gliadin in Crumb of Bread from High-Protein Wheat Flours of Varied Breadmaking Potential.

M. Menkovska, Y. Pomeranz, G. L. Lookhart, and M. D. Shogren. Copyright 1988 by the American Association of Cereal Chemists, Inc. 

Gliadins extracted from flours and bread crumbs of six high-protein hard red winter wheats that varied widely in breadmaking potential were examined by polyacrylamide gel electrophoresis (PAGE) and high- pressure liquid chromatography (HPLC). Four of the HRW wheats consisted of two pairs of sister lines. The gliadins in the six flours (including the sister pairs) differed in their PAGE patterns. Generally, slow- moving (relative mobility [RM] values below 40) PAGE bands (omega-gliadins) extracted from bread crumb were more pronounced than those from wheat flour. The reverse was true for fast moving (RM values above 40) PAGE bands (alpha-, beta-, and gamma-gliadins). Generally, the change from flour to bread crumb was more pronounced in good breadmaking flours than in poor breadmaking flours. The flours also differed in their gliadin HPLC elution patterns. Differences in HPLC-separated gliadin bands between pairs of sister lines were small. There were relatively small changes (from flour to bread crumb) in HPLC elution bands below 20 min; elution bands above 20 min were consistently reduced in intensity from flour to bread crumb. The extent of reduction in peak intensity was much higher in good- than in poor- breadmaking quality flours. It is postulated that heat-labile alpha-, beta-, and gamma-gliadins (the highly hydrophobic gliadins) are modified during baking and that the modification may be related, in part at least, to differences in breadmaking potential of wheat flours.