Formation of oil-in-glycerol/water emulsions

Oil-in-glycerol/water emulsions at various ratios of water to glycerol in the external phase were prepared with Tween 80 and either light mineral oil or soybean oil. A minimum in the droplet size was observed at about 15% w/w water in the external phase of the emulsions. At the same water concentration, a clouding of the surfactant occurs at room temperature and the surface and interfacial tensions are minimal. It appears, therefore, that the minimum droplet size of the emulsions is related to the clouding phenomenon, as a result of changes in the properties of the solvent and the surfactant.