Effect of cysteine on structural, rheological properties and solubility of wheat gluten by enzymatic hydrolysis

P>The progressive enzymatic hydrolysis of wheat gluten was obtained with Fourier transform infrared spectroscopy structural and rheological understanding of the molecular interactions and structural transformations as affected by cysteine. Cysteine which cleaved disulphide (SS) bonds and inhibited wheat gluten polymer formation induced the disappearance of 1622 cm-1 band (extended structures) and significant increases in the amount of beta-sheet in the amide I region and in hydration capacity. The alterations in structure had tremendous influence on the rheological properties of wheat gluten so that decreased the shear moduli (loss modulus and storage modulus) and viscosity. A typical viscoelastic behaviour (ranging from more solid-like to more fluid-like) affected by cysteine was manifested by wheat gluten dough. Consequently, the solubility of wheat gluten improved. Hence, structural, rheological changes and solubility gave rise to high enzymatic hydrolysis of wheat gluten.