Functional Properties of Wheat Glutenin

Abstract

Abstract The importance of glutenin in bread-making quality has led to a substantial research effort. Studies on glutenin can be grouped into four categories: studies that determine the statistical relationships between the quantity of fractions and quality, studies of reconstitution and fortification, breeding and genetic modification, and those that assess structure–function relationships during processing. Statistical relationships between glutenin, glutenin fractions and glutenin polypeptides and quality have been established. The SDS or acetic acid unextractable glutenin correlated strongly with quality parameters. For highMrglutenin subunits the relationships with quality are less strong. In some studies it was demonstrated that the presence of some highMrglutenin subunits is correlated with the quantity of unextractable glutenin. Therefore, subunits are probably indirectly linked with bread-making qualityviathe quantity of unextractable glutenin. Recombination and fortification studies are hampered by changes in functionality of proteins after their separation. Recently, small scale tests have been developed in which small amounts of glutenin fractions can be studied. Controlled breeding studies have demonstrated the importance of highMrglutenin subunits 5+10 and, to a lesser extent, 1 or 2* for quality. In most of these studies the quantity of unextractable glutenin is not reported. This hampers adequate conclusions on cause–effect relationships. During dough processing large changes occur in the extractability of glutenin. The significance of these changes for dough properties and bread quality still requires investigation.