Effect of sugars and salts on rheological properties of Balangu seed (Lallemantia royleana) gum

Abstract

The effect of different sugars (sucrose, glucose, fructose, and lactose) and salts (NaCl and CaCl2) at various concentrations on rheological properties of Balangu seed gum (BSG, 1% w/w) was investigated. The apparent viscosity was influenced by the sugars and salts concentration and shear rate. Synergistic interaction between BSG gum and sugars improved the viscosity of solutions, whereas addition of salts decreased viscosity of gum solutions. The Power law and Herschel–Bulkley models were fitted to shear stress–shear rate data to obtain the consistency coefficient (K) and flow behavior index (n) for BSG solutions. Power law model well described non-Newtonian pseudoplastic behavior of BSG. Both K and n were sensitive to sugars and salts concentration. Highest values (0.45–0.49) of flow behavior index were observed for glucose at all concentrations. Addition of sucrose, fructose, lactose and salts to BSG led to more pseudoplastic solutions, whereas glucose decreased pseudoplasticity of solutions.