When selecting the solvent we should use to extract the oil from the plant we have to consider, will the extract need to be winterized if the product is to be winterized then we are more limited in the solvents we can use for the original extraction.

We can obviously discount the ones That may be toxic or have residues the best way to cheque for residues is to place a small amount of your chosen solvent onto a glass surface and allow it to evaporate, the glass surface should be clear from any residual marks or residue, every ethanol I tested had residues remaining on the glass this is what inspired me to distil our own ethanol for winterization.

Jeffrey Ditchfield the supplier to Manuel Guzman used acetone extraction with no winterization, Jeffrey later produced several other batches which were winterized the initial extraction for these was also acetone. The winterization process was then carried out with ethanol.

The solvent with a red background in our opinion should not be used in extraction or in winterization, some of the big pharmaceutical companies use Hexane to winterize and ethanol to extract you would then need to use a solvent Polar such as water to remove the remaining Hexane from the extract this is a step which the most pharmaceutical companies have failed in doing.

The solvents marked with green we would consider prime candidates for extraction whether you’re going to winterize or not, in my working experience for the most part acetone un1090 was the main solvent used for extraction and ethanol would be the perfect remaining candidate for winterization.

In a perfect world then I would choose CO2 to extract when Co2 for extraction it will strips out the majority of wax from the plant so winterization would be necessary and ethanol would be used for winterization.

If you want to know more about solvents and how they are used please talk to a professional chemist.

*Boiling points – are measurements for 1 atmosphere – air pressure at sea level