Fresholi

Supercritical CO2 extraction is a process of extracting essential oils from plant material using compressed carbon dioxide at very high pressure and extremely low temperatures.

The resultant essential oil/extract is considered superior to those extracted by steam distillation because it obtains more top notes, more esters (considered anti-inflammatory, calming and non-hazardous), less terpenes and a larger number of volatile molecules.  An essential oil extracted using this method contains no residues, is very pure and stable. 

CO2 extraction is a rather expensive process but the aromatic quality is superb and generally, a small amount goes a very long way.