Sodium oleate is an emulsifier, a chemical compound that is soluble in water. It is a common ingredient in many soaps and detergents, as well as industrial lubricants and cosmetics.
Oleic acid is one of the most common monounsaturated fatty acids in nature. It is found in a variety of animal and vegetable fats and oils. It is also the main component of olive oil, which is a staple in Mediterranean diets.
The synthesis of oleic acid begins with the 9-desaturase action of stearoyl-CoA in a process called stearic acid dehydrogenation. During this process, oleic acid enters a series of reactions that give carboxylic acids and alkenes. The result is the formation of oleic acid and other unsaturated fatty acids such as palmitic, stearic and linolenic.
Solubility varies depending on the composition of the product, its temperature and other factors. It is therefore important to determine the molecular structure of a product prior to using it as an emulsifier.
Various ionic and nonionic surfactants are commercially available for emulsification. Some are sorbitol monooleates (Span 20 and Tween 80) and others are phospholipids derived from ethoxylated sorbitan.
Other ionic surfactants, such as amorphous octadecanoate (AOT), are often used for emulsification purposes because they do not interact with lipids in the oil phase, thus reducing the mass transfer of the emulsifier between the two phases.
AOT is a good choice for stabilization of oil-in-water emulsions because it has high ionization strength, low mass transfer and a relatively low breakthrough pressure when dissolved into the water phase. Moreover, AOT has good stability when diluted in the water phase, and it is a good stabilizer for saline solutions and other salty emulsions.