CO2 Supercritical and Subcritical Extracts

CO2 Extract Benefits

• CO2 Extracts are closer in composition to the fresh botanical than are extracts and oils produced via other methods.

• Steam distillation is only able to collect molecules of the lightest weight. CO2 extraction allows a larger range of constituents to be collected.

• CO2 Extracts are more stable and possess a longer shelf life than their essential oil, absolute and vegetable oil counterparts.

• Low temperatures are maintained during the CO2 supercritical extraction process. The production of essential oils via steam or hydro-distillation requires the use of heat that can cause degradation or alteration of the natural aromatic molecules present in a botanical. Likewise, expeller pressing, and even cold pessing, results in the oil being exposed to heat.

• Carbon dioxide (CO2) in its supercritical or subcritical state acts as a solvent that is far superior to the solvents used to produce aromatic absolutes or solvent extracted lipids. Carbon dioxide is safe, and no trace of CO2 remains after the extraction is complete.

[Source: Mark Webb, Course: CO2 Extracts: The How, What, Where, When & Why. v1.3 - v1.6. 2017-2019.]

CO2 Supercritical Extracts

CO2 Extracts are classified into two primary categories: CO2 Supercritical Extracts and CO2 Subcritical Extracts.

To product CO2 supercritical extracts, carbon dioxide is carefully pressurized and converted into what is known as a supercritical state. When carbon dioxide is in a supercritical state, it is not considered to be a liquid or a gas.

CO2 Total Extracts

CO2 Total Extracts are produced using CO2 supercritical extraction. They are typically extracted at higher pressures than are CO2 Select Extracts (described below). CO2 Total Extracts generally contain both volatile and non-volatile CO2-soluble components of the botanical. Depending on the plant part used, the aromatics, heavier waxes, fatty acids, resins and color compounds may be present in the extract. CO2 Total Extracts typically consist of molecules ranging between C5 to C60. CO2 Total Extracts are generally thicker in consistency than are CO2 Select Extracts. However, CO2 Total Extracts are soluble in lipophilic fluids such as essential oils and vegetable oils. Due to their viscosity, some CO2 Total Extracts may need gentle warming.

CO2 Select Extracts

CO2 Select Extracts are CO2 Supercritical Extracts that are generally extracted at lower pressures than are CO2 Total Extracts. Select Extracts typically contain the more volatile CO2-soluble components with molecules consisting of molecules ranging between C5 to C25. The heavier waxes, resins, and color compounds are generally not present in CO2 Selects. These extracts somewhat resemble steam distilled essential oils in composition and beneficial applications, however, they typically offer more volatile components that cannot be extracted using steam distillation.

CO2 Subcritical Extracts

The CO2 subscritical extraction process is similar to that of the supercritical extraction process except that the temperature and/or pressure used intentionally does not permit the carbon dioxide to reach the supercritical phase. CO2 subcritical extraction typically extracts the most lightweight aromatic molecules that have carbon structures ranging between C5 to C22. Essential Oils typically consist of aromatic molecules ranging in size from C5 to C20. Of all the classifications of CO2 Extracts, CO2 Subcritical Extracts most closely resemble the consistency and aroma of essential oils. However, CO2 Subcritical Extracts tend to be aromatically superior to their essential oil counterparts.