The rheological behaviour of whey protein isolate-stabilized emulsions was investigated in the presence of gum arabic (0-15) The flow behaviour of the emulsion was observed to be pseudoplastic at all gum concentrations. The increase in ionic strength reduced the magnitude of the apparent viscosity indicating that electrostatic interactions between the high molecular weight polysaccharide molecules influenced the rheology of the system. The viscosity changed with particle size and the concentration of unbound polysaccharide in the emulsion. The apparent viscosity data was described with the empirical power law equation. Temperature dependency of the viscosity was given with an Arrhenius type relationship. An ernpirical equation was developed for the prediction of activation energy as a function of shear rate. (C) 2002 Elsevier Science Ltd. All rights reserved.