Cereal Chem 58:317 - 324.  |  VIEW ARTICLE
Effects of Neutral Salts upon Wheat Gluten Protein Properties. I. Relationship Between the Hydrophobic Properties of Gluten Proteins and Their Extractability and Turbidity in Neutral Salts.

K. R. Preston. Copyright 1981 by the American Association of Cereal Chemists, Inc. 

The effects of increasing concentrations of neutral monovalent sodium salts upon the extractability and turbidity of wheat gluten proteins was studied. At low salt concentrations (less than 0.05M) extractability was almost independent of anion type. However at higher salt concentrations (0.5-4.0M), gluten protein extractability was highly dependent upon anion type and followed the lyotropic anion series (in increasing order): F-, Cl-, Br-, ClO4-, SCN-. Similar results were obtained by measuring the turbidity of 0.05M acetic acid-soluble gluten proteins after addition of various levels of salts. At low salt concentrations turbidity increased in the presence of all salts, but at higher salt concentrations turbidity was dependent upon anion type. Electrophoretic and amino acid analyses showed differences in the properties of the gluten proteins extracted by the various salts. These results suggested that at low salt concentrations the solubility and aggregation properties of gluten proteins are largely determined by ionic interactions, whereas at higher salt concentrations hydrophobic interactions predominate. In addition, wheat gluten proteins appear to vary widely in their hydrophobic properties.