Chemical composition of olive oil
Triglycerides (saponificabile part) 98/99%.
Unsaponifiable fraction 0.5 / 1.4%
Within the triglycerides, fatty acids are numerous, but the most important and characteristic are: oleic and linoleic acid. The oleic acid should not be less than 73% and the linoleic acid should not exceed 10% with an oleic / linoleic ratio greater than or equal to 7.
In the unsaponifiable fraction which is the minor component there are important compounds:
• Hydrocarbons, including squalene
• Phytosterols, in particular beta-siterol
• Liposoluble vitamins like beta-carotene
• Pigments, such as chlorophyll
• Superior aliphatic alcohols and triterpenic alcohols
• Polyphenols (2-3%) with antioxidant activity
Among these, polyphenols are particularly important, in particular oleuropein. Oleuropein is responsible for the bitter taste of the fruits and leaves of the olive tree, it plays an important protective action against oxidation. In vitro (mg / kg) it has been shown to be a “nutracetic” substance, that is to say it is a nutrient and a drug. Oleuropein has a positive effect against the proliferation of leukemic cells.
The above characteristics are only virgin oil, because the pomace oil has a higher percentage of linoleic acid (from 9.5% to 15.5%) and there is also the presence of another acid that is completely absent in oil virgin. It is elaidinic acid, which is the trans isomer of oleic acid and therefore can increase the incidence of cardiocirculatory diseases.