Cannabidiol (CBD) is the non-psychoactive compound found in the hemp plant that has been linked to several potential health benefits, including pain and stress relief. Since its legalisation in 2018, CBD products have filled the shelves of shops in the UK, but how does it get from plant to product? Well, before CBD can make its way into our wellness routine, it undergoes an important extraction process.

Depending on what extraction method is used, this can have a significant impact on the quality of the final product. After all, not all CBD is made equal!

In this article, we explain everything you need to know about CBD extraction, including the types of extraction, what each one means for the results, and what you need to look out for when you’re purchasing a CBD product.

What is CBD Extraction?

Hemp plants are rich in over 500 natural compounds, including CBD, THC, terpenes and flavonoids. CBD extraction involves isolating CBD from the other compounds to separate and obtain a CBD-rich oil from plant material. This extract is then used in various products, such as oils, tinctures, edibles and topicals. There are four main types of CBD extraction, each with a varying impact on the final product.

Supercritical CO2 Extraction

Considered the gold standard in CBD extraction, the CO2 extraction method uses carbon dioxide in its liquid and gas states to extract CBD from the hemp plant.

A closed-loop system carefully controls temperature and pressure to turn CO2 into a supercritical state. This supercritical CO2 acts as a solvent, which “pulls” CBD and other beneficial compounds from the plant, while leaving behind any unwanted plant material.

This method is environmentally friendly and preserves the integrity of the natural compounds, resulting in a pure and high-quality CBD extract.

co2 extraction diagram

It is also possible to have subcritical CBD extraction with CO2, which relies on a lower temperature and less pressure to pull CBD from the hemp plant. Although this takes longer and results in a smaller amount of CBD, this makes it harder for compounds to get damaged, and allows more delicate compounds to be extracted.

Solvent-Based Extraction

This technique uses solvents, like ethanol or butanol, to strip CBD from the plant material. This is a cheaper method of extracting CBD, but requires careful post-extraction processing to eliminate any residual, toxic solvents. Likewise, solvents can remove chlorophyll, a pigment that helps the plant perform photosynthesis, which can create a bitter taste and unpleasant side effects, such as nausea and stomach cramps.

Due to the higher cost associated with natural solvents, some manufacturers choose to go with synthetic solvents which results in a lower quality product that is sometimes unsafe for consumption if the solvents haven’t been removed. In addition, solvent extraction can sometimes alter the natural profile of the extracted compounds, making them less effective.

solvent extraction diagram

Olive Oil Extraction

Olive oil extraction involves heating hemp and olive oil to extract CBD. This method is often attempted by home enthusiasts looking to create their own CBD. While possible, it’s not as efficient as other methods and often results in less potent CBD with a much shorter shelf life, making it an unsuitable method for mass producers.

olive oil extraction diagram

Ice Water

Ice water extraction involves using dry ice — which has no denaturing solvents —  to yield a clean and pure CBD extract. This technique involves flash-freezing loosely-chopped hemp extract using dry ice, and then filtering out the frosted trichomes (plant hairs) through a mesh bag to create a residue that forms the basis of CBD oil. This is another method for home enthusiasts, which removes the need for any type of solvent.

ice water extraction diagram

 

Each extraction method will result in a different type of CBD, depending on what the manufacturer wants to create. The three main types of CBD are —

  1. Full-Spectrum CBD: contains all occurring compounds found in the hemp plant, including other cannabinoids (THC), terpenes, and flavonoids.
  2. Broad-Spectrum CBD: similar to full-spectrum CBD but contains no Tetrahydrocannabinol (THC), which means it is certified drug-free and has no psychoactive properties.
  3. Isolate CBD: isolated and purified to remove all other compounds, including other cannabinoids, terpenes, and flavonoids.

 

What Is the Best Extraction Process for CBD Oil?

For reputable CBD producers, CO2 extraction is the best extraction process for CBD oil. It is quick and gentle on the active ingredients in the hemp plant, and creates a safe and high-quality product with a high yield.

Regardless of the type of extraction, rigorous testing should be carried out to verify the potency and purity of the CBD, and to ensure the absence of harmful contaminants. Reputable manufacturers should provide third-party laboratory reports that detail the composition and purity of their products, the absence of harmful substances, and that the THC levels comply with industry guidelines and regulation.

With all this in mind, we would recommend that you:

  • Choose products that use CO2 extraction, which often yields safer and higher-quality extracts.
  • Select products derived from organic hemp to minimise your exposure to pesticides and other harmful chemicals.
  • Check products have clear labels indicating the CBD content per serving. You should also look for third-party lab reports which detail the contents of the product.
  • Choose products made with broad-spectrum CBD if you want optimal results but want to avoid consuming THC (to avoid the risk of a positive drug test, for example).

 

At Purity Hemp, quality is at the heart of everything we do. From the organic hemp we grow on our farms in nutrient-rich soil and clean water sources, to our sustainable and quality-assured farming processes, to the CO2 extraction process (with patented tech) that we use to extract a CBD-rich oil, we’re committed to supplying a premium range of organic CBD products to our customers.