LAOS behavior of the two main gluten fractions: Gliadin and glutenin

Abstract

Crude gliadin and glutenin fractions were studied using Large Amplitude Oscillatory measurements. LAOS measurements were carried out at three different frequencies (20, 10, 1 rad/sec) between the strain values of 0.01e200%. The beginning of non-linearity for glutenin occurred at~2.5%, while an initial region of strain hardening was observed for gliadin (2.5e10%) at 1 rad/sec frequency and up to 15% at the higher frequencies applied. Lissajous curves showed in the elastic analysis of both fractions glutenin was more elastically dominated since Lissajous curves were narrower, while for gliadin the ellipses were much broader suggesting more fluid-like behavior and each ellipse depended on the magnitude of frequency. Decreasing frequency increased the viscous behavior of both glutenin and gliadin in the nonlinear region, but the change in gliadin was much more pronounced. Gliadin molecules only display intramolecular disulfide bonds creating a great deal of mobility whereas for glutenin molecules, which contain both intermolecular and intramolecular disulfide bonds, the strong network structure formed by this molecular arrangement results in very pronounced strain stiffening.

Large amplitude oscillatory shear (LAOS) measurements as a promising tool to predict electrospinnability of pectin solutions

“…In viscous curves, the stress response to applied strain rate diverges from a straight line or narrowish elliptical shape to a larger ellipse or perfect circle as the material shows more elastic behavior. 26,32 Both elastic and viscous data confirmed one another, suggesting a profound contribution of PEO 2000 to the elasticity of the polymer solution at all pectin concentrations. These results are in agreement with the results of the study conducted in the linear region (1-10% strain) of the polymer blends to relate smooth nanofiber formation to the rheological properties of pectin and PEO blends.…”

Impact of formulation on high‐protein bar rheological and wear behaviors

“…LAOS has been used to better understand their microstructures and large‐strain viscoelastic behaviors of multiple foods. Such foods include gluten‐free flour dough (Yazar, Duvarci, Tavman, & Kokini, ), blue cheese (Joyner (Melito), Francis, Luzzi, & Johnson, ), mashed potatoes (Joyner (Melito) & Meldrum, ), locust bean gum gels (Sousa & Gonçalves, ), tomato paste, and mayonnaise (Duvarci, Yazar, & Kokini, ).…”

Synergistic Effect of Metagenome‐Derived Starch‐Degrading Enzymes on Quality of Functional Bread with Antioxidant Activity

“…The bands with the molecular weight of 34-55 kDa can relate to the low molecular weight glutenin subunits (30-55 kDa) [53] or gamma (30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40), and omega (55-180 kDa) gliadin subunits. [55] Also, the 25 kDa band can be related to the beta gliadin subunits. [54] The gliadin and glutenin are the major wheat storage proteins that are responsible for the viscoelastic behavior of the dough and specific volume and firmness of bread.…”