An emulsifier (also known as an "emulgent") is a substance that stabilizes an [emulsion] by increasing its kinetic stability. One class of emulsifiers is known as "surface active agents".
An emulsion is a mixture of two or more liquids that are normally immiscible (nonmixable or unblendable). In an emulsion, one liquid is dispersed in the other. Examples of emulsions include vinaigrettes, milk, mayonnaise, and some cutting fluids for metal working.
There are two types of emulsions depending on the composition of the phases. In an oil-in water
emulsion such as milk and mayonnaise, the water is the external phase and the oil is the internal phase. In a water-in-oil
emulsion such as butter, the oil is the external phase and the water is the internal phase. By use of the proper emulsifier, the two phases will mix and separation is prevented or delayed.Emulsifiers in food
Emulsifiers are among the most frequently used types of food additives. They are used for many reasons.Emulsifiers can help to make a food appealing. The example of the mayonnaise without the emulsifier shows how unappealing it would be if the oil and water separated before it was used. Emulsifiers have a big effect on the structure and texture of many foods. They are used to aid in the processing of foods and also to help maintain quality and freshness.
Foods that Commonly Contain Emulsifiers
Biscuits,Toffees, Bread, Extruded snacks, Chewing gum, Margarine / low fat spreads, Breakfast cereals, Frozen desserts, Coffee whiteners, Cakes, Ice-cream, Topping powders, Desserts / mousses, Dried potato, Peanut butter, Soft drinks, Chocolate coatings, Caramels.
In pharmaceutics, hairstyling, personal hygiene, and cosmetics, emulsions are frequently used. These are usually oil and water emulsions but dispersed, and which is continuous depends in many cases on the pharmaceutical formulation.
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