Rheological properties of high-pressure treated xanthan gum and guar gum blend solutions: A response surface approach

In this research, the impact of pressurization (300-600 MPa) on the oscillatory rheology of a blend of xanthan gum (XG) and guar gum (GG) in solution (XG/GG) was examined at a selected gum concentration using a response surface methodology. Three independent variables pressure (0.101-600 MPa) concentration (0.75%-1.25%), and temperature (40-70 degrees C)-were employed to maximize the dynamic moduli (G', G '', and eta*) of the blend solutions. The developed model suggested that all the linear, two quadratics (concentration and temperature), and two interactions (concentration-pressure and concentration-temperature) terms were significant (p < 0.05) for the dynamic moduli (R-2 = 0.99) with insignificant lack-of-fit. The pressure-induced mechanical rigidity was found to be higher when compared with the heat-treated solutions, which requires further comprehensive structural assessment to endorse the order-disorder transition produced by high pressure. The superposition principles correlating time-temperature and time-pressure adequately fit the pressurized blend solutions.