Rheological properties of wheat gluten and their relation to molecular parameters

In the light of the general results of protein chemistry and of the interrelationships up to now established, it is stated that the factors which determine the mechanical properties are complex in nature. Though the amino-acid composition (cystine content, amino acids with hydrophobic side-chains) and the ratio of the wheat gluten fractions (ratio of high molecular protein components to low-molecular ones) exert some effect on the rheological properties, the linkages and the interactions between the different fractions play the main role in the development of the mechanical properties of the gluten. Among the various linkages and interactions which occur in protein architecture, the disulphide linkages, the hydrogen bonds (amido group, primary amino group) and the hydrophobic interactions (side-chains of proline, leucine, isoleucine, glutamine, etc.) are of great importance. The complex evaluation of data about the content of disulphide linkages, the degree of amidation of the glutamic and aspartic acids and the amount of amino acids with hydrophobic side-chain gives a significant insight which might be of practical value.