Cannabis extracts are beneficial because extraction allows for higher cannabinoid purity, accurate dosing, and strong, longer-lasting concentrates.
Crude Extract-CO2 and Ethanol
The simplest form of extracts are called “crude extracts,” and the most common methods are ethanol and CO2.
Ethanol is a popular extraction method in the cannabis industry because it’s efficient, however it tends to leave a lot of byproducts in the remaining cannabis oil, and some terpenes and aromatic compounds don’t mix with alcohol, so they’re lost in the process.
To make an ethanol extract, dried or fresh cannabis is mixed with an industrial-grade grain alcohol like high-proof, flavourless vodka. The cannabis is agitated and left to marinate in the alcohol, which binds with the cannabinoids and draws them out into the liquid. Then, after almost all of its cannabinoids have been mixed into the alcohol, the cannabis is strained out.
Finally, the alcohol is removed from the mixture, leaving a pure cannabis extract containing the cannabinoids and terpenes, as well as some of the plant compounds like chlorophyll and vegetable waxes.
CO2 extraction is similar to ethanol, except that instead of mixing cannabis with alcohol, it’s mixed with Carbon Dioxide (CO2). When carbon dioxide is held under super high pressure, it becomes a liquid, and when liquid CO2 is mixed with cannabis in a pressurized container, the CO2 rapidly absorbs the cannabinoids from the cannabis. After the liquid CO2 is infused with cannabinoids, the pressure is released and the CO2 turns back into a gas, leaving behind a thick oil full of all the goodness of the cannabis.
CO2 is considered to be a higher-quality extraction method because it removes more cannabinoids and terpenes without damaging them, which retains more of the character of the cannabis used for extracting. It also leaves almost no residue, whereas ethanol often leaves a small amount of alcohol behind.
Crude vs. Distillate vs. Isolate
Crude extract is sometimes turned into cannabis distillate. A cannabis distillate is a crude extract that’s been distilled – just like vodka or whiskey. The extract is heated until it turns into a vapour, and then the cannabinoids are separated from the rest of the compounds in the extract. This allows a cannabis producer to “clean up” crude extract, concentrating the cannabinoids by removing impurities like chlorophyll and plant matter. A crude cannabis oil normally contains 40-60% cannabinoids. A distillate will normally contain 90-99% cannabinoids. The tradeoff is that cleaning up the crude cannabis oil also removes things like terpenes that give the oil its unique flavours. However, skilled extractors are often able to either retain the terpenes in a distillate, or recombine them into the final product.
Isolate is distillate which has been taken one step further: cannabinoids are put through a further clarifying process that removes everything except the pure cannabinoid itself. Isolates are typically 98-99.9% pure, and are normally used for things like creating cannabis medicines and capsules.