A new synergistic hydrocolloid with superior rheology: Locust bean /xanthan gum binary solution powdered by different drying methods

Abstract

In the current study, a novel gum powder containing locust bean and xanthan gums was prepared by three different drying methods of their synergistic aqueous solutions: direct cabinet drying (CD), drying after alcohol precipitation (PD), and direct freeze drying (FD). The purpose of this process is to develop ready-to-use synergistic gum powders with improved rheological properties by modifying intermolecular interactions. Significant improvements in viscosity, consistency efficiency and pseudoplastic character were observed for PD, followed by CD and FD, as well as the higher values of G′ and G″ values of PD, indicating a stronger entanglement network development between the macromolecules for PD. PD exhibited better elasticity and shear resistance compared to FD and CD in the strain sweep test. In Lissajous curves, straight line shapes were found for synergistic solutions at low strain, which continued for increasing strain values for PD and CD. However, the pronounced viscous behavior was found for FD at 500% strain. Compared to CD and FD, PD exhibited a more desirable thixotropic character. A lower zeta potential was observed in the production of synergistic gums using the PD process. Gel strength was found to be higher for PD. Therefore, PD was a more effective method to produce a ready-to-use synergistic powder with better viscoelastic properties and a more stable solution.