Knowing extra virgin olive oil and its properties
Olive oil is a vegetable fat, made mostly of triglycerides (neutral fats) and in lesser quantity by phospholipids, glycolipids and sterols. Triglycerides are composed by a glycerol molecule bound (esterified) to three molecules of fatty acids.
In olive oil there are the following fatty acids:
- oleic acid (70-80%)
- palmitic acid (10-15%)
- stearic acid (5-8%)
- linoleic acid (10%)
- linolenic acid (2-3%)
As we can see, in olive oil there is a net prevalence of monounsaturated oleic acid, a modest percentage of saturated fatty acids (palmitic and stearic) and a moderate percentage of essential polyunsaturated fatty acids (linoleic and linolenic). Indeed, olive oil is a good alimentary source of unsaturated fatty acids, which aren’t sinthesizable by humans and so must be supplied through the diet every day. For this reason these unsaturated acids are considered “essential fatty acids”.
In olive oil glycerides constitute the saponifiable fraction (98-99%), while the rest is called unsaponifiable1 and makes up the remaining 1-2%.
The unsaponifiable fraction is composed of chlorophyll, carotene, anthocyans, waxes, squalene, sterols, aromatic compounds, tocopherols and polyphenols. In particular, the unsaponifiable fraction composed of polyphenols and tocopherols is recognized as having antioxidant and anti-inflammatory properties, helpful to prevent cardiovascular and tumoral diseases. These molecules, in addition to carrying out an antioxidant and anti-inflammatory function, are also an excellent alimentary source of vitamins.
1 It’s the fraction that doesn’t produce glycerine when treated with alkali.
