Cannabidiol, or CBD, is one of the cannabinoids found in the cannabis plant that has gained a huge following for its touted anecdotal medicinal benefits. It is useful for alleviating symptoms associated with stress, pain relief, insomnia, and several other conditions. It has also recently been approved by the FDA as a treatment for epilepsy conditions.
To make CBD oil or tincture, the CBD is extracted from a hemp plant and diluted with a carrying agent. Extraction has become a hot topic of late, and the nuances in the extraction process can alter the end product.
How CBD is Extracted:
CARBON DIOXIDE (CO2)
One of the most popular extraction methods for CBD oil involves the use of CO2. This system takes advantage of CO2’s unique properties that allow it to function in solid, liquid, and gas states of matter. Closed-loop extractors are most commonly used for this process.
CO2 extraction starts with a solid piece of CO2 that gets pumped into a second chamber containing cannabis material. The chamber is kept at such a pressure that the CO2 stays in a liquid-like state and absorbs the oils and flavors of the plant. Then, the CO2-cannabinoid mixture gets pumped into a third chamber where the CO2 is allowed to return to a gas state, leaving behind the oil and flavors from the plants.
The idea of using liquid to absorb CBD oil from the cannabis plant doesn’t stop with CO2. Substances which are more naturally in a liquid state are also used, including ethanol, butane, hexane, or isopropyl alcohol. This process works much the same as the CO2 extraction process.
Liquid solvent extraction is a cheaper, easier way to extract CBD oil, but it has its downsides. Certain solvents may carry impurities and chlorophyll from the plant, which can give the oil a greenish tinge and a bitter taste. However, adjusting the extraction process can minimize most of these risks.
Oil infusion is one of the most ancient techniques for harvesting CBD oil. In fact, many home growers and producers still use this method today. It’s one of the most straightforward methods, but it does come with some drawbacks.
Before you start oil infusion, you must first decarboxylate the plant material, or heat it to a certain temperature to activate the compounds. Then you add it to olive oil or a similar carrier oil and heat it at 100 C for an hour or two. You can’t evaporate olive oil out of the CBD oil, so one of the primary downsides is you have to use a lot more oil to get the same effect.
After extraction, the next steps are winterization and distillation.
An important part of harvesting pure, high-quality CBD oil is winterization. This is the process to remove undesirable substances from the oil so you wind up with pure CBD. It is important to note that this is a part of harvesting CBD isolate, not full-spectrum CBD, which keeps those substances in it.
Once you have the oil extracted, you combine it with 200-proof alcohol and freeze it overnight. In the morning, it will be ready to run through a filter, which can remove the fats and other such materials. When the oil is of the quality you want, you can heat the mixture to the boiling point of alcohol (which is lower than that of CBD oil) and boil off the alcohol.
If you want to further refine the oil you’ve gotten, you can run it through a process called short path distillation. This takes advantage of the fact that different compounds in CBD oil each have their own boiling point. To obtain the purest CBD oil, you can boil off the different compounds that have a lower boiling point than the oil itself.
Short path distillation starts by slowly heating your CBD mixture until the extraneous substances begin to boil off. The vapors formed by this process travel through a distillation tube until they reach cooling coils, where they condense. From there, they drip down into a separate collection container, and the process continues until only pure CBD oil is left.
Consider the Source
When selecting a CBD product, it’s incredibly important to look at each step’s source, growing practices, extraction, and formulation.
Unfortunately, due to the continuing legal battles surrounding cannabis products, there are not very many standards in place for the CBD oil industry. This means a lot of companies may try to sell you something that is either impure CBD or not CBD oil at all. It’s important to be careful when buying CBD oil and only buy from companies with a trusted reputation.
Groups such as the Foundation of Cannabis Unified Standards (FOCUS) and American Society for Testing and Materials (ASTM) are working on creating standards for the CBD industry. These standards cover things such as cultivation, extraction, laboratory conditions, infused products, security, and more. As more and more states legalize marijuana and cannabis products, we’ll likely see a set of universal standards adopted in the near future.