CBD Extraction Techniques: Supercritical CO2 or Ethanol?

The debate surrounding which CBD extraction method is superior rages on, and for good reason. Both supercritical CO2 and ethanol extraction have pros and cons. However, we feel our proprietary ethanol extraction is the best method for producing authentic full spectrum CBD oil. Additionally, our in-house chromatography technique enables us to selectively pull THC from our oil, creating a unique broad spectrum (THC free) CBD oil.

Here, we break down the differences between the two most commonly used CBD extraction methods (ethanol vs. CO2) to help clear the air.

Extraction methods are various processes used to procure and concentrate the medicinal compounds found naturally in hemp.

There is no absolute ‘best method’ when it comes to CBD extraction methods, and it truly depends on what you’re trying to create. In a nutshell, supercritical CO2 is used for producing highly-refined CBD isolates.

In contrast, ethanol is the go-to when opting for a full-spectrum CBD oil with a wide range of beneficial phytonutrients.

Supercritical carbon dioxide (CO2) extraction has exploded in popularity and is arguably the most common choice amongst CBD companies. The question remains, though, as to whether or not that’s a good thing. Let’s explore this topic further.

Supercritical Carbon-Dioxide (CO2) CBD Extraction

Supercritical CO2 extraction requires the use of costly and technologically advanced equipment, and also a well-trained technician to operate the machine.

This particular technology has applications in many areas other than hemp, such as:

• Sterilizing tissues and organs for transplants
• Extracting fat from snack foods
• Removing caffeine from coffee to make decaf
• Extracting flavor oils from hops

This process involves starting with gaseous CO2 and transforming it into a liquid by cooling it to under -69°F (-56°C) and applying 75 pounds of pressure per square inch.

At this point, the CO2 is now liquid, so the technician gradually increases the temperature and pressure until the fluid reaches a ‘supercritical’ state, meaning that it possesses both the properties of a gas and a liquid.

This dynamic allows for the supercritical CO2 to fill up a chamber like a gas, but soak the extraction material (hemp) like a liquid. 

CO2 extraction is recognized in the cannabis industry for having an incredibly low environmental impact. Compared to a butane/propane extraction, CO2 is promoted as one of the safest techniques. However, despite these positives, CO2 is not without its flaws.

After the CO2 passes over the hemp, it goes through a separation chamber, where changes in temperature and pressure allow the CO2 to evaporate and leave behind cannabinoids, terpenes, and wax. The CO2 vapor then passes through a condenser to be returned to its liquid state and saved for future use.

CO2 extraction is often marketed as ‘solvent-free,’ suggesting it is a cleaner alternative to other extraction methods. However, this is usually not the case.

The resulting extract, while full of cannabinoids and terpenes, requires winterization due to the high content of wax and lipids. The most commonly used solvents for this purpose are ethanol (ironic), isopropanol (petroleum-based), or methanol (toxic wood-alcohol). 

Most companies using CO2 extractions perform winterization through distillation, which is typically performed at very high heat. In this common method the two benefits of CO2 are lost; a solvent is still employed ("solvent free" therefore is not accurate) and the hemp extract is subjected to high heat (the cold benefits of CO2 are lost).

Furthermore, (and more importantly if you are consuming hemp-derived products for therapeutic benefits), this lengthy purification process, which is required to remove the co-extracted constituents (waxes and plant fats) from the extract, can take away from the final cannabinoid and terpenoid profile.

A study published by Planta Medica in March of 2018 found that CO2 extraction drastically changed the chemical composition of cannabis. Compared with the dried plant flower, CO2 extracts eliminated many of the subtle flavor and aroma molecules that provide nuance and subtlety to the experiential effects of different cultivars.

Advocates of CO2 extraction tout the non-polar nature of carbon-dioxide, meaning that it doesn’t pull out any of the water-soluble components in hemp.

However, this is only a benefit if your end goal is to make CBD isolate, as most experts agree that the full range of compounds found in hemp provides a unique therapeutic synergy known as the ‘entourage effect.’

One sure benefit of this method is that CO2 effectively eliminates any unwanted microbes, assuring that the end product is free from mold and mildew.

While it is a fairly rare occurrence, there are unfortunate deaths related to CO2 extraction from time to time, as a leak of carbon dioxide can go undetected due to the lack of smell or visible fumes - which can ultimately lead to a deadly build-up of CO2 in the environment, causing asphyxiation. 

Alcohol (Ethanol) CBD Extraction

Cannabis is a fascinating plant that can produce more than 500 compounds that represent almost every biogenetic class. As such, we choose to utilize ethanol extraction to create the most full-spectrum CBD product possible. 

Ethanol is simply, alcohol. It is made from plant fermentation and is a by-product of plants themselves.

Ethanol is a polar solvent, allowing it to extract both water and fat-soluble plant compounds, such as: 

• Cannabinoids (CBD, THC, CBC, CBG, CBDV)
• Terpenes (myrcene, limonene, pinene, linalool, b-caryophyllene, terpinene, eucalyptol)
• Polyphenols
• Lignans
• Chlorophyll
• Flavonoids (apigenin, luteolin, kaempferol, quercetin, and cannflavin A and B)
• Amino acids (all eight essentials)
• Alkamides (immune-promoting compounds)

In our ethanol extraction, food-grade ethanol is passed through the hemp flowers and brought to a very low boil. During this simmer, we gently cradle the flowers as they mix with the ethanol and create natural friction, producing a vapor that is full of beneficial compounds. We then recirculate the ethanol through the plant matter multiple times, allowing for maximum extraction.

Our sophisticated ethanol extraction process effectively removes undesirable plant waxes and chlorophyll without the high-heat exposure used in other extraction methods.

Ethanol has been referred to as "the best of both worlds". This extraction method is recognized for having the efficiency of a butane extraction while maintaining the safety of CO2. The FDA classifies ethanol as safe for human consumption and therefore it is commonly used as a food preservative and food additive. 

Now that we’ve talked in-depth about the two primary extraction techniques, let's discuss the bottom line on choosing which extraction method you should look for in your CBD products.

Petroleum-Based Hemp Extraction

Petroleum-based solvents, such as Butane and Propane, were among the first extraction methods used by farmers, cannabis growers and home-grown CBD enthusiasts. These solvents work well due to their non-polarity, meaning they allow for the extraction of all the desired compounds (such as cannabinoids and terpenes) from the plant material without also extracting undesirable compounds (such as chlorophyll and plant metabolites). The problem with this extraction process is that it involves high heat and high pressure, is highly combustible and highly toxic, ruling out being a viable option by many health and wellness companies.

While petroleum-based solvents have their purpose, in a commercial setting, typically a solvent-based approach or a super critical (CO2) extraction are performed for feasibility and cost efficiencies.

How Do We Ensure Our Products are Clean and Solvent-Free?

We employ distillation techniques to remove the solvent from the extract. Our testing protocols test down to 1 part per million (1ppm) in which no ethanol is found in our extracts.

We strive to keep our products as natural and as close to the hemp plant as possible. Ethanol is well-known in the herbalism world to be the most natural and efficient solvent to get the most beneficial compounds from the plants. These methods have been employed for hundreds, if not thousands of years which is why most of the larger herbal companies are still using ethanol extraction over CO2.

The cannabis industry will continue to emerge with new technologies, making consumption more efficient, effective and more accessible. However, this doesn't always equate to a better solution for extraction. We have found what works best for us in order to provide our customers with the healthiest products that have true therapeutic potential.

We passionately believe the 500+ phytonutrients extracted from hemp via ethanol extraction offer a far superior user experience to the isolated CBD that results from CO2 technology.

However, some people may prefer to use CBD isolate, due to the perceived 'purity' or 'simplicity' it offers. While we at Ananda Hemp certainly advocate for the use of full spectrum, ethanol extracted CBD, there is nothing wrong with using CO2 extracted isolate if that is what you prefer. 

As always, do your research and make sure to read CoA’s thoroughly.

To your health and happiness, always!