Describe the properties of gum ghatti

Important property of gums referred to as 'viscosity' and the effets of pH. Gum ghatti does not form true aqueous solutions but form viscous dispersions in water (having a pH of about 4.8) at concentrations of about 5% or higher and exhibits typical  non-Newtonian behaviour common to most hydrocolloids. The viscosity remains more or less constant upto pH 7 and then drops off gradually down to pH 12. At all pH values, viscosity increases noticeably overtime upon ageing. The gel fraction of ghatti, responsible for its viscous behaviour, is predominantly calcium salt. Removal of the calcium ions  reduces the viscosity; however, the original viscosity cannot be restored by the addition of calcium ions.