What is oleic acid?

Oleic acid is a monounsaturated fatty acid from the omega 9 family of fatty acids.

It is mainly present in oils of vegetable origin such as olive oil, avocado oil, safflower oil, or canola oil.

Olive oil is composed of between 61 and 83% oleic acid, depending on the variety and climate. The amount of oleic acid in the oil does not depend on the quality of the oil; nor of its form of extraction, mechanical or through chemical solvents; or if the olive oil has been refined.

Characteristics of oleic acid

The main feature of oleic acid is that it is the most stable unsaturated acid:

• It is more stable against oxidation than polyunsaturated fatty acids (omega 6 and omega 3)
• It is more stable at high temperatures than polyunsaturated fatty acids (omega 6 and omega 3). For this reason, olive oil is more stable than sunflower oil when frying, since the latter is mainly composed of linoleic acid (omega 6).

Health benefits of oleic acid

Many of the beneficial properties of olive oil come directly from oleic acid. The main benefit of consuming oleic acid is its protective nature of the cardiovascular system with several mechanisms: firstly, it helps to reduce blood pressure, and secondly, to reduce bad cholesterol and increase good cholesterol (More on the effects of oleic acid and olive oil on cholesterol).

You can see all the beneficial properties of olive oil by following the link below.

Physical properties of oleic acid

Chemically isolated oleic acid is a colorless and tasteless liquid.

Its melting point is 15 ºC. Hence, olive oil solidifies when the temperature drops below this limit.

Its boiling point is 360 ºC. Although culinarily speaking and for its use in the kitchen, the smoke point or smoke temperature is more relevant, which sets an upper limit to the maximum temperature that can be used in frying without decomposing.  Thus, olive oil, composed mainly of oleic acid, has a smoke point below 220 ºC.

Chemical formula of oleic acid

The molecular formula of oleic acid is C₁₈H₃₄0₂.

The molecule of oleic acid, like all fatty acids, has a carbon chain structure where at one of the ends the functional group C-O-OH is located.

Within the carbon chain, in the carbon that occupies position number 9 counting from the functional group, there is a double bond with the following carbon, this is what gives oleic acid its monounsaturated character. It is a fatty acid of the omega 9 family. Many of its health properties are derived from this chemical characteristic.

Amount of oleic acid in olive oil

Most of the olive oil is made up of oleic acid. However, the amount varies depending on the variety of olives with which the oil has been made. There are varieties that naturally tend to contain a bigger proportion of oleic acid. We have attached a table with some varieties of olive oil and an orientation on the amount of oleic acid they contain.

Amount of oleic acid in other vegetable oils

Each vegetable oil has a certain proportion of different fatty acids in its composition. The fatty acid part of the oils is called the saponifiable fraction. A chart of the saponifiable fractions of various vegetable oils can be viewed here.

Other foods rich in oleic acid

In addition to most vegetable oils, in which oleic acid can be found to a greater or lesser extent, another source of oleic acid is nuts: almonds, peanuts, hazelnuts, pistachios and walnuts.

Also, although to a lesser extent, in some meats such as pork.

What is high oleic sunflower oil?

High oleic sunflower oil is sunflower oil from sunflower plants that have been genetically modified to produce more oleic acid. It is widely used in the food service industry.