APPLICATION OF RHEOLOGICAL ANALYSIS TO W/O/W MULTIPLE EMULSIONS - EFFECT OF THE INCORPORATION OF A COEMULSIFIER

The present study deals with the improvement of a water/oil/water (W/O/W) multiple emulsion by incorporating a coemulsifier into the external water phase. The use of interfacial tension measurements led to an optimized emulsifier-coemulsifier pair. Oscillatory and flow theological analyses proved to be very efficient in the study of both the structure of the multiple emulsion at 20 and 40 degrees C, and the kinetics of release induced by a swelling step followed by rupture of the multiple droplets. Therefore by the incorporation of a coemulsifier, the compacity, elasticity and temperature stability of the multiple emulsion could be considerably increased as well as the kinetics of release sustained.