Although botanical extraction has been practiced by various cultures for thousands of years, it’s only recently that the means by which you can produce essential oils, resins and waxes from plant material have become widely available and more affordable to the indoor gardener.
Why would you want to make your own extracts? Because plants are awesome! Extracts can be used in making your own soap and perfume, as a relaxing aromatic or in massage oil, or even in the kitchen as food and drink flavoring (hello lavender martini!).
So, how exactly do you end up with plant extracts? Here are 3 of the most common methods used by hobbyists today:
Ice Water Extraction – Ice water extraction is performed by agitating plant material in an ice water bath within mesh net extraction bags (also known as bubble bags or drop bags). Ice water extraction can be used to make extract for oils, topicals and edibles, and more often will yield more end product than other methods. This method is generally regarded as cheap and easy, although it may require slightly more time to produce extract compared to the other methods. Advantages this method has are that it is natural and organic (as it doesn’t require any additional chemicals to perform), and if done properly with quality starting material the extract purity rivals the other methods. However, a downside to this method is that it doesn’t remove any contaminants or impurities from the starting material, so make sure to start with clean, pesticide-free plants!
CO2 Extraction – Carbon dioxide (CO2) extraction involves passing highly compressed (supercritical) CO2 gas through plant material under pressure, separating the extract from the plant. CO2 extraction is used to make extracts for food, body care and aromatherapy, and generally produces a highly concentrated end product. Since carbon dioxide is nontoxic and odorless, when using food or instrument grade CO2 this method is natural and safe, and doesn’t require any other chemicals for extraction. In addition, CO2 extraction can remove mold, mildew and bacteria during the process. One big disadvantage to this method is that the equipment costs are expensive so it generally isn’t used outside of large commercial applications very often.
BHO (Solvent) Extraction – Butane honey oil (BHO) extraction is a solvent-type extraction method where first pressurized butane is used to separate the extract from the plant material, and then the butane is separated from the extract. Extracts produced with this method tend to be waxier than other methods, although the end product is highly concentrated. As it is less expensive than CO2 extraction and relatively fast to do, this method has gained popularity recently. However, due to the chemicals involved, this method can be very dangerous if not performed under proper conditions, and can also transfer chemicals to the extract or impart an aftertaste if the butane used is not high quality. Another disadvantage this method has is that it requires more equipment than ice water extraction.
Stay tuned for Part 2 of our Extraction series, where we’ll go over some of the more common extracts and how they’re used!