How Is CBD Extracted From Hemp?

CBD is the buzzy new wellness ingredient. Everyone wants to get their hands on it, but where is it actually coming from?

CBD stands for Cannabidiol, a compound belonging to the family of Cannabinoids that are naturally occurring in the Cannabis plant. The Cannabis sativa plant family can be roughly divided into marijuana and hemp. While both contain CBD, hemp conveniently contains very low (less than 0.2%) levels of THC compared to marijuana and can be grown legally by farmers in many countries of the world. That is why CBD is extracted from dried, milled hemp raw material. 

Depending on the purification steps following the first extraction, different kinds of extracts from full- to broad-spectrum all the way to CBD isolate can be produced. However, every single process starts and is characterized by choosing a method for this first extraction, so let’s take a look at the most common options.

CBD Alcohol Extraction

The alcohol used for extraction is most commonly ethanol or isopropyl-alcohol, both of which are solvents commonly used in food-grade manufacturing. The plant material is saturated with it, then the solution containing the extract components is filtered off the mix and the alcohol is removed from it by distillation. 

The resulting so-called crude extract then undergoes further distillations to remove, for example, chlorophyll (the green color of plants) or unwanted cannabinoids like THC while enriching the desired cannabinoids like CBD.  

Alcohol extraction is the most commonly used method of CBD extraction worldwide. The solvent can be recycled and used for the following extraction, which makes this method cost-efficient and preserves resources. It also doesn’t require any too specialized equipment. 

CBD CO2 Extraction

If you’ve read a bit about CBD extraction, you probably came across CO2, the solvent that is hailed for being the cleanest around. Usually, CO2 is a gas, but when the pressure and temperature are adjusted correctly, it can be a so-called “supercritical fluid” that is used as a solvent in extractions. 

In principle, the extraction process is the same as with alcohol, with the difference that a more sophisticated setup is needed to deal with the high pressure resulting from the use of liquid CO2. On the upside, more points of adjustment can allow for the exclusion of more unwanted components from the start, and the solvent (CO2) can simply be evaporated at the end of the process without leaving any traces in the product. 

CO2 extraction gained popularity in recent years, however, the high running costs and specialized equipment that is needed might be why it isn’t able to take the pole position from alcohol extraction. 

 

CBD Oil Extraction

Cannabinoid extraction using vegetable oils is probably the method that has been around for the longest time historically, which is why it deserves to be mentioned here.  The oil is “infused” with hemp raw material, which slowly releases its oil-soluble components, very much like when brewing a cup of tea. 

The big drawback is that the oil can’t be easily removed, which means the cannabinoid concentration in the resulting product remains relatively low and it’s not possible to selectively remove unwanted components like THC. Vegetable oils are also relatively expensive and ineffective solvents when compared to CO2 or alcohol. 

CBD Butane Extraction

Just like ethanol and CO2, butane can be used as an effective solvent for cannabinoids if passed over the milled, dried plant material. Its initial appeal is the high volatility, which makes it possible to remove all traces of this solvent either by applying a bit of heat or a slight vacuum. However, it is also highly explosive and flammable, which makes it difficult to work with this solvent under safe working conditions. Furthermore, it is not a preferred solvent to be used in food products. 

The resulting extract still includes high levels of terpenes and natural levels of THC and is usually not refined any further.

CBD Rosin Extraction

This method produces products very similar to butane extraction, but entirely without the use of solvents. Instead, high pressure and heat are used to gain a resinous extract directly from the plant material. The higher the pressure that can be applied, the less heat has to be used, which leaves valuable terpenes intact. 

This method has become more and more popular with smaller-scale producers looking for full-spectrum extracts, still including the natural levels of THC, terpenes and other plant compounds.

Conclusion

As you can see, there is more than just “the one” method of extracting CBD from hemp. The method of choice depends on different factors, like the intended use of the extraction product and economical and environmental considerations, as well as equipment available. The bottom line is that while all of the above-mentioned methods can deliver a clean extract, it´s always best to check the COAs provided by the manufacturer to ensure that the final product is safe to use.

written by

anna falk - head of product

Anna Falk is Head of Product at Harmony. Anna obtained her PhD degree in Organic Chemistry with highest honours and has a combined 9 years of experience in R&D, project, and product management across the fields of natural product synthesis, catalysis, and cosmetics. She has produced award-winning, internationally published research at the Universities of Berkeley, Edinburgh, and Cologne.

Leave a comment