Rheological properties of mixed polysaccharides and polysaccharide‐thickened emulsions

Steady flow and viscoelastic properties of mixed‐polysaccharides and mixed‐polysaccharide‐thickened oil‐in‐water emulsions are investigated with a cone‐and‐plate system using a controlled‐stress rheometer. The mixed‐polysaccharide system studied is xanthan gum and guar gum. The rheological properties of the mixed‐polysaccharide systems exhibit strong synergistic effects. For a total polysaccharide concentration of 0.75 wt. % investigated, the synergistic effect is maximum at a xanthan:guar ratio of 15:85. The oil‐in‐water emulsions, prepared from a mixed‐polysaccharide system as the suspending medium, are strongly shear thinning and highly viscoelastic in nature. The rheological parameters such as apparent viscosity, storage, and loss moduli increase with an increase in the oil concentration of the emulsion.