Cereal Chem 42:215 - 235.  |  VIEW ARTICLE

A Study of the Relationship Between Viscoelastic Properties and the Chemical Nature of Wheat Gluten and Glutenin.

J. E. Barney II, H. B. Pollock, and C. C. Bolze. Copyright 1965 by the American Association of Cereal Chemists, Inc. 

The effect of variations in the level of water, pH, salt, urea, lipids, soluble proteins, free amino groups, free carboxyl groups, and free sulfhydryl groups on the viscoelastic properties of crude gluten, purified gluten, and glutenin has been studied. Both stress-strain and stress-relaxation curves were obtained on the three materials with an Instron tensile-testing machine. Functions related to the stress-relaxation modulus and the distribution function of relaxation times were calculated from these curves, and the effects of the variables on them were determined with standard statistical methods. Among the conclusions reached in these studies are: the viscoelastic properties of crude gluten are primarily determined by the level of water present; complete acetylation of free amino groups destroys the cohesiveness of gluten; methylation of crude gluten decreases its strength relative to purified gluten and glutenin, possibly because of a modification of the starch in the crude gluten; the level of lipids had no effect on viscoelastic properties. Electron micrographs of stressed, chemically modified crude gluten support some of these conclusions.