Improved emulsion stability and resveratrol encapsulation by whey protein/gum arabic interaction at oil-water interface

Abstract

This work studied the effects of different concentrations of gum arabic (GA) on the interfacial adsorption kinetics of whey protein (WP) at the oil–water interface, the possibility of emulsion stabilized by WP/GA mixtures, and use of such emulsions as resveratrol delivery systems. Dynamic interface pressure measurements indicated that the change of GA concentration significantly affected the diffusion, penetration and rearrangement of WP at the oil–water interface, while measurements of hydrodynamic diameter and ζ-potential indicated electrostatic and hydrophobic interactions between WP and GA. The rheological measurements of the emulsions supported the above observations and indicated that different GA concentrations affected the viscoelastic properties of the emulsion. Adding resveratrol into oil influenced the adsorption of WP at the oil–water interface, thus affecting the emulsion stability and the encapsulation efficiency of resveratrol. The emulsions stabilized by WP and WP/GA mixtures have encapsulation efficiencies of >50% for resveratrol, while emulsions showed the best stability at a GA concentration of 0.2%. These results indicate that GA could effectively improve the emulsifying capacity of WP, while the emulsions prepared by WP/GA mixtures have the potential to serve as carriers for bioactive components.