Factors Affecting Stability of Multiple Emulsions, and Criteria for Their Stabilisation

Factors Affecting Stability of Multiple Emulsions, and Criteria for Their Stabilisation 

It is clear that the stability of the resulting multiple emulsion depends on a number 

The main criteria for the preparation of a stable multiple emulsion are  

The amount of emulsiflers used in the preparation of primary and multiple emulsion is critical. Excess emulsifier I in the oil phase may result in further emulsification of the aqueous phase into the multiple emulsion, with the ultimate production of a W/O emulsion. Excess emulsifier II in the aqueous phase may result in solubihsation of the low-H LB surfactant, with the ultimate formation of an O/W emulsion. 

Optimum osmotic balance of the internal and external aqueous phases. If the osmotic pressure of the internal aqueous droplets is higher than the external aqueous phase, water will flow to the internal droplets and result in swelling of the multiple emulsion drops with the ultimate production of a W/O emulsion. In contrasL if the osmotic pressure in the outside external phase is higher, water will diffuse in the opposite direction and the multiple emulsion will revert to an O/W emulsion. 

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