All the cannabidiol (CBD) you find in your favorite gummies, drinks, and oils has to go through an extraction process first. CBD, for those who don't know, is a cannabinoid found in cannabis. Extracting CBD involves isolating the chemical compound from the surrounding plant material and distilling it in high concentrations. Research has shown that cannabinoids may have beneficial effects on physical and mental health, and extraction makes it possible to consume more of those cannabinoids with less effort.
In this article, you'll learn about how CBD is extracted from hemp and cannabis, as well as which extraction process yields the best results.
How to extract CBD from cannabis
Extracting cannabinoids from cannabis or hemp can be as simple as making cannabutter at home. But for large-scale manufacturing purposes and more potent results, there are two primary methods for efficient CBD extraction. Each method presents distinct benefits in creating a high-quality, highly-potent CBD product.
Carbon dioxide (CO2) extraction method: Carbon dioxide is a versatile gas with a variety of commercial uses, including extracting compounds from plant matter. The CO2 method uses the gas in its normal state as well as in supercritical liquid form. Through the use of a pressurized chamber, called a closed-loop extractor, CO2 gas is compressed until it becomes a liquid. The liquid is forced over the cannabis material where it strips away cannabinoids like CBD. The entire solution is brought back to temperatures and pressures at which the CO2 reverts to gas and evaporates, leaving behind the CBD extracted out of the cannabis plant material.
Andrew Leising, VP of Strategic Sourcing for Balanced Health Botanicals, elaborated on the process: “CO2 is a scalable and highly versatile form of extraction. There are CO2 extraction units built to process anywhere from 1 to 1,200 pounds of biomass in a single run. With CO2 extraction, you can not only extract cannabinoids on a large scale efficiently, you can extract specific compounds like terpenes.”
Terpenes are the naturally-occurring compounds that infuse cannabis with its signature aromas and flavors as well as potential therapeutic benefits. Full-spectrum CBD products rely on extraction methods that can keep these compounds intact.
Solvent extraction method: The solvent extraction process is similar to using CO2, but it's notably cheaper and faster. Butane has long been used in cannabis extraction but ethanol and propane are also popular. This method also uses a closed-loop system wherein the liquid butane, propane, or ethanol washes over the cannabis, releasing the CBD, other cannabinoids, and terpenes. The solvent then has to be carefully heated or cooled to separate the solvent from the extracted compounds without damaging them. The main drawback of solvent extraction is that some solvents may extract impurities from the cannabis plant material, which could give the end-product an unpleasant taste.
Both of these extraction methods use highly combustible chemicals and can be dangerous. Only trained professionals in properly equipped labs should attempt any kind of chemical extraction.
How long does CBD extraction take?
The process of CBD extraction is fairly expedient and can take place in a single afternoon. According to Leising, it takes about three to four hours to process up to 1,200 pounds of cannabis.
What happens after CBD oil extraction?
After CBD oil is extracted from hemp or cannabis, the process of winterization begins. This process removes the impurities and unwanted elements that made it through the extraction process, such as fats, lipids, and waxes. In essence, winterization transforms crude oil into purified oil. The process gets its name from a step which involves mixing the extracted oil with ethanol and freezing the solution. The impurities and undesirable compounds solidify and fall out of the solution, which is then passed through a filter, separating wax, lipids, and fats from the oil. The final step involves removing the ethanol from the solution.
CBD may go through further refinement after winterization to create the purest possible CBD product. The additional refinement phase is known as short-path distillation. The process is similar to winterization, but it involves using reduced pressure to allow lower-than-normal boiling temperatures. The solution is heated just enough for the impurities to boil off and travel a short path out of the system, leaving pure CBD oil to distill into the collection chamber.
Which CBD extraction method is best?
Many cannabis experts agree that the CO2 method is best for producing premium oil that stays potent longer because the hemp or cannabis compounds remain stable during this type of extraction. Full-spectrum CBD oil, prized for its potency and purity, is made via CO2 extraction. Other methods may destabilize the compounds, potentially creating lower-quality CBD oil with a shorter shelf life.
Leising agrees that the CO2 method is superior. As he shared, “CO2 is generally preferred for the extraction of cannabinoids that are meant for ingestion or further refinement. Due to the nature of the extraction process, you can be assured that your extracted oil will be free of any residual solvents, microbes, and fungi.”
The same is not true for the solvent method, which often fails to eliminate such impurities.
Can I extract CBD oil at home?
It depends on what extraction method you're considering. Let's say you have a thriving indoor cannabis garden and want to consume the cannabis you've harvested without having to smoke it all. You can safely make CBD oil at home via a simple infusion and consume a high concentration of cannabinoids without risking life or limb.
What you don't want to do is attempt to make a CBD extract using inedible solvents or CO2. Leising explained, “You cannot perform CO2 extractions at home. The equipment is cost prohibitive, and if you don't know how to operate the equipment, it could be extremely dangerous. The equipment runs at extremely high pressures between 2500-4000 PSI and could be very dangerous if the operator is not properly trained.”
Bottom line: don't risk your life for CBD oil. Visit a reputable dispensary and shop for high-quality, lab-tested products instead.