Fatty acids are molecules composed of carbon, hydrogen, and oxygen. They differ from one another based on the number of carbon atoms bonded together to form chains of varying length and on the type of bond linking them, whether single or double. When double bonds are present between carbon atoms, they are referred to as unsaturated fatty acids; when the chain consists only of single bonds, they are known as saturated fatty acids.
Saturated fatty acids account for approximately 15% of the fatty acids in olive oil. Because they are solid at room temperature, they are partly responsible for the cloudiness that may appear in olive oil during the winter months, when temperatures drop.
Monounsaturated fatty acids, which contain a single double bond in the chain, are represented mainly by oleic acid, which makes up the majority of the fatty acids in olive oil.
Polyunsaturated fatty acids, which contain more than one double bond in the chain, are particularly important because they cannot be produced by the human body and must therefore be obtained through the diet; for this reason, they are also referred to as “essential” fatty acids. Linoleic acid and linolenic acid, the polyunsaturated fatty acids found in olive oil, belong to the well-known Omega-6 and Omega-3 families.