Olive oil is composed mainly of the mixed triglyceride esters of oleic acid and palmitic acid and of other fatty acids, along with traces of squalene (up to 0.7%) and sterols (about 0.2% phytosterol and tocosterols).
Olive oil contains phenolics, such as esters of tyrosol, hydroxytyrosol, oleocanthal and oleuropein,[REF][REF] having acidic properties that give extra-virgin unprocessed olive oil its aroma and bitter, pungent taste [REF].