An emulsion is a fusion of fatty and aqueous molecules of varying stability. It involves dispersing a “phase”, broken down into small drops, in another, non-miscible “phase” to create a homogeneous mixture.
An emulsion is unstable by nature, and over time the two phases separate. This is what happens, for example, when a stirred mixture of oil and water is left to stand. To prevent this separation from occurring, we need to add an emulsifier whose molecules are part-soluble in water and part-soluble in oil, so it works at the boundary between the two phases to keep them bonded for longer.
The emulsion technique is very important in gastronomy. It is used in everything from sauces to mousses, creams, ice creams, sponge cakes and ganaches.
There is now a very wide range of “new” emulsifiers which, thanks to their increased efficiency and neutrality, allow us to achieve one of modern cuisine’s obsessions: purity of flavour. They also open up the possibility of new applications, such as foams and texturizing fats.
Stabilizers for ice cream or sorbets are complex mixtures of thickeners, emulsifiers, gelling agents and aerators that provide a very easy way to make perfect ice cream or sorbet textures. They always preserve the flavour to which texture is being added.