Release Properties and Stability of Double W-1/O/W-2 Emulsions Containing Pumpkin Seed Oil

摘要

The double Water-in-Oil-in-Water emulsions containing a mixture of pumpkin seed and sunflower oil were prepared with polyglycerol polyricinoleate (PGPR) as a hydrophobic emulsifier and different hydrophilic emulsifiers, whereby Tween 20 showed the best stabilization effects. Two different stabilization methodologies of the Water-in-Oil emulsions, (1) stabilization against molecular diffusion degradation (Oswald ripening) by electrolyte (NaCl) addition and (2) gelling of internal water droplets using alginate to form gel phase were employed. Emulsion with co-stabilizer was more stable during storage and heating/freezing treatment than Gel-in-Oil emulsions. Glucose was introduced as a thickening agent in the external water phase. The regulation of the osmotic pressures between the water compartments by glucose addition to the external water phase can be employed to modulate the release behavior of encapsulated material and improve the droplet stability. Also, simple correlation was proposed to predict the release fraction of the salt toward the external water phase.