Investigation and comparison of intrinsic viscosity and coil overlap parameter of Iranian and commercial locust bean gums

In this research, Iranian locust bean gum (LBG) was extracted from carob seeds collected from Fars province and purified locust bean gum was produced using isopropanol. A commercial type locust bean gum was also used for comparison. Solutions of the three gums were prepared and using U-tube viscometry critical concentration, intrinsic viscosity and coil overlap parameters were determined. For Iranian LBG, Iranian purified LBG and commercial LBG, critical concentrations were 0.6, 0.25, and 0.15% (w/v) and intrinsic viscosities were 3.95, 9.05 and 9.48 (dL/g), respectively. Both Iranian and commercial LBGs were capable of viscosifying aqueous solutions, however the commercial LBG was stronger and able to produce viscous solutions at lower concentrations. The results showed that purification process increases the intrinsic viscosity and decreases critical concentration of Iranian LBG to a great extent. Coil overlap parameter was also measured for the three LBG samples.