An emulsifier ( also called leavening agent ) It is a substance which stabilizes an emulsion, frequently a surfactant. Examples of food emulsifiers are egg 40 yolk; where the main emulsifying chemical is lecithin ) honey and mustard, where a variety of chemicals in the mucilage around the seed pod acting as an emulsifier; proteins and low molecular weight emulsifiers are the most common. In some cases, particles can stabilize emulsions through a mechanism called Pickering stabilization. Both mayonnaise and hollandaise sauce are oil emulsions in water are stabilized with egg yolk lecithin. Detergents are another class of surfactant, and may interact chemically with oil as the water, thus stabilizing the interface between the droplets of oil or water in suspension. This principle is exploited in SOAP to remove grease for the purpose of cleaning. A wide variety of emulsifiers are used in pharmacy to prepare emulsions such as creams and lotions. Among the most common examples are the wax emulsificadora, cetearil alcohol, polysorbate 20 and 20.1 ceteareto also known as emulsification.Sometimes the same internal phase can act as an emulsifier, and the result is a nanoemulsion the internal state is dispersed into droplets size nanometer within the external phase.? A well-known example of this phenomenon occurs when water is poured into a drink of high alcohol content based on anise, like ouzo, the pastis or raki. Anisolicos components, which are soluble in ethanol, form droplets size nanometer and emulgen into the water. The color of this diluted drink is opaque and Milky.