Emulsion and Lipid Microcapsules
Emulsion Oil in water emulsion (O/W) is typically a ‘mayonnaise’ kind of mixture. Water in oil emulsion (W/O) will be typically a ‘butter’ kind of mixture. Lipid booster have been traditionally been sold as oil in water (O/W) emulsions.
Oil microcapsules Oil micro capsules are the new generation boosters. Emulsified fish oils are not perfect because they provoke an important bacteria bloom during enrichment and because their formula is limited to the use of lipid soluble nutrients. On the contrary, oil microcapsules offer little or no available nutrients for the growth of bacteria during enrichment and broaden the formulation to any kind of water-soluble or oil soluble nutrient.
An oil microcapsule is formed by first emulsifying an oil into water. Carefully selected polyelectrolyte are adsorbed on each oil droplet to form a first interfacial surfactant complex at the oil/water interface. Subsequently, the deposition of two polyelectrolytes complex coacervates takes place (ex: gelatine-acacia capsule). The encapsulated agent is in the internal phase (oil), which allows working without solvent. An optimal formulation was developed offering high encapsulation yield, optimal elastic behaviour and a regular smooth membrane thickness of approximately 700 nm.