What are emulsions? What are their different types? Give example of each type.
An emulsion is a mixture of two or more liquids that are normally immiscible (non-mixable or unblendable). It means that in an emulsion the dispersed phase and dispersion medium are both liquids. There are two basic types of emulsions: oil in water and water in oil. In every emulsion, there is a continuous phase (dispersion medium) that suspends the droplets of the other element which is called the dispersed phase. (i) Oil-in-water emulsions (O/W): The emulsion in which oil is present as the dispersed phase and water as the dispersion medium (continuous phase) is called an oil-in-water emulsion. Milk is an example of the oil-in-water type of emulsion. In milk liquid fat globules are dispersed in water. Other examples are vanishing cream etc. ii) Water-in-oil emulsion (W/O) : The emulsion in which water forms the dispersed phase, and the oil acts as the dispersion medium is called a water-in-oil emulsion. These emulsions are also termed oil emulsions. Butter and cold cream are typical examples of these types of emulsions. Other examples are cod liver oil etc.
