Oleic acid

A type of monounsaturated fatty acid present in olive oil.
Generally speaking, fats are made up of a fraction (approx. 90-99%) that is glyceridic in nature, and include a considerable number of microcomponents: the non glyceridic or unsaponifiable fraction (0.4-5%, which rises in certain oils to the decidedly higher value of 12%).

The glyceridic fraction is made up of triglycerides, diglycerides, monoglycerides and phospholipids. The triglycerides, diglycerides and monoglycerides present a molecule of glycerol to which molecules of fatty acid (three, two or one, respectively) bind.

According to their origin, we may distinguish between oils on the basis of the fatty acids that are present in each and every drop.

All fatty acids are made up of a chain of carbon atoms to which oxygen and hydrogen are bound. We may distinguish between fatty acids on the basis of the number of carbon atoms present. The acids include butyric acid, with four carbon atoms (typical in butter), capric acid, myristic acid, palmitic acid, stearic acid, oleic acid (abundant in olive oil), linoleic acid, and linolenic acid, as well as long-chain fatty acids such as montanic acid, with twenty-eight carbon atoms.

The carbon atoms that form the chains of fatty acids may be linked the one to the other by single bonds or double bonds. Fatty acids may be grouped in three separate categories on the basis of the presence, or absence, of double bonds in the chain of carbon atoms.

The absence of double bonds is associated with the presence of saturated fats, particularly abundant in fats of animal origin. The presence of merely one double bond indicates the presence of monounsaturated fatty acids, such as oleic acid. The presence of two or more double bonds in the chain of carbon atoms indicates the presence of polyunsaturated acids (typical in seed oils).