Essential oil are volatile aromatic organic compounds extracted from aromatic plants by distillation, extrusion, cold soaking or solvent extraction.

Also known as volatile oil— a kind of oily liquid,which can volatilize at normal temperature and are water immiscible.

Essential oil are composed of terpenes, aldehydes, esters, alcohols and other chemical molecules.

Because it is oily, it is called “oil”, but it is essentially different from the vegetable oils we see everyday.  The main components of vegetable oils are triglycerides and fatty acids.