Effect of electrolytes in the water phase on the stability of W1/O/W2 double emulsions

This study aimed to improve the physicochemical stability of water-in-oil-in-water (W-1/O/W-2) double emulsions using different formulations that influence the inner emulsion fraction (water-in-oil (W/O) type: 10 %, 20 %, 30 %, 40 %, and 50 %) and osmotic agents (NaCl, KCl, MgCl2, and Na2CO3). The stabilities of the double emulsions were analyzed for 60 d based on the droplet size, charge, viscosity, and encapsulation efficiency (EE). From the results of the inner emulsion fraction, the double emulsions showed the smallest droplet size at 50 % inner emulsion fraction, regardless of the osmotic agent. The viscosity and EE of the double emulsions increased as the inner emulsion fraction increased. The droplet size of the double emulsion increased in the following order: nonelectrolyte (control)

Automated summary

The study aimed to improve the physicochemical stability of water-in-oil-in-water double emulsions by using different formulations. The results showed that the smallest droplet size of the double emulsions was observed at 50% inner emulsion fraction, regardless of the osmotic agent. The viscosity and encapsulation efficiency of the double emulsions increased with increasing inner emulsion fraction.