TRIGLYCERIDE MICROEMULSIONS - EFFECT OF NONIONIC SURFACTANTS AND THE NATURE OF THE OIL

The phase behavior of mixtures of food grade surfactants and various t riglycerides was investigated to prepare oil-in-water microemulsions ( L(1)) for food uses. Water-in-oil microemulsions (L(2)) were easily fo rmed at a ratio of 75/25 wt % ethoxylated monodiglycerides/monoglyceri de. This ratio was found to be optimal for the formation of an extende d triglyceride microemulsion area which approached the aqueous corner of the phase diagram where oil-in-water microemulsions (L(1)) are pres ent. Blue-phase regions, which are extremely stable emulsions, were id entified. These regions consisted of droplets separated by layers of l amellar liquid crystals. Sucrose enhanced the formation of the L(1) ph ase while destroying the L(2) phase. Triglycerides containing unsatura ted or short-chain fatty acids had improved solubility in L(1)-type mi croemulsions compared to triglycerides with saturated or long-chain fa tty acids.