Submitted to: Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 23, 2006
Publication Date: October 15, 2006
Citation: Xu, J., Bietz, J.A., Carriere, C.J. 2006. The viscoelastic properties of wheat gliadin and glutenin suspensions. Food Chemistry. 101(3):1025-1030. Interpretive Summary: Wheat proteins are important in food and non food applications. However, the properties and the structure function relationship of wheat protein are still not clearly understood. This study was aimed at investigating the structure function relationship of two wheat protein fractions gliadin and glutenin. Using rheological measurements, we studied viscoelatic properties of gliadin and glutenin suspensions. A functional role for gliadin was discovered which can benefit scientists in the bread industry and food science and technology, and development of non food applications and biomaterials. We find that gliadin plays an important role in adjusting the viscoelastic behavior of gluten. Therefore, this information is crucial for the bread industry and new biomaterial development.
Technical Abstract: Linear and non linear rheological properties of wheat gliadin and glutenin suspensions were investigated at various concentrations. Linear dynamic viscoelastic properties for both gliadin and glutenin were strongly dependent on concentration. For gliadins, the storage moduli (G'), loss moduli (G"), and phase shifts dramatically changed within a narrow concentration range, indicating that gliadin suspension properties changed from viscous to viscoelastic. Glutenins exhibited viscoelastic solid behavior at all measured concentrations. The non linear shear viscoelastic properties of gliadin and glutenin also depended on concentration. Viscosities of gliadins displayed shear thinning behavior; viscosities for glutenins showed shear thickening behavior at low shear rates, and shear thinning behavior at higher shear rates. Our results indicate that gliadin's structure in suspension changes over a small concentration range, and suggest that gliadin is important in adjusting and controlling gluten's viscoelastic behavior, and not only as a diluent of gluten's functional properties.