Science Explained – Emulsions

Defining ‘Emulsion’

An emulsion is a dispersion of two or more immiscible liquids held in suspension by substances called emulsifiers.


Emulsions can be used across a range of application areas, including Personal Care and Cosmetics, Household Cleaning and the Food & Beverage sector.

Oil-in-water emulsion – An oil-in-water emulsion is a mixture in which oil (the dispersed phased) is dispersed in water (the continuous phase). Small droplets of oil are dispersed in water to form an oil-in-water emulsion.

Water-in-oil emulsion – A water-in-oil emulsion is a mixture in which water (the dispersed phase) is dispersed in oil (the continuous phase). Small droplets of water are dispersed in oil to form a water-in-oil emulsion.

Water-in-silicone emulsion – Silicone emulsions are insoluble silicones evenly dispersed in water with the aid of an emulsifying surfactant. Many colour cosmetics products, such as foundations, tend to be this emulsion type.


Emulsifier Benefits

Emulsifier – surface active agent that stabilises oil in water (or vice versa). Fatty chain in the oil droplet while water-loving head sits on the outside. Emulsifiers contain a hydrophilic element (water loving) and lipophilic element (oil loving). In simpler terms, they are attracted to both oil and water elements, allowing them to bind the two together to form a stable formulation.

  • Upon selecting an effective emulsifier, it allows formulators to create homogenous mixtures, dispersions and/or emulsions of oily or waxy substances with water.
  • Adding one or more emulsifiers supports the dispersion of solids in liquids or insoluble liquids with other liquids.
  • Greasy anhydrous creams can be modified to form washable ones.

Variables for Emulsion Selection

When selecting the most suitable emulsifier for a formulation, it is important to consider the below…


Personal Care Emulsifiers

To find out more about cold process emulsions, click here

Household Care Emulsifiers

About ‘Science Explained’

The 2M Group of Companies has a long-term commitment to Science, Technology, Engineering and Maths (STEM) education.  Over the last few years, we are proud to have educated both children and adults, demonstrating the opportunities within the industry. Our ‘Science Explained’ series aims to broaden our education reach, and encourage STEM learning across all ages.