Cannabis extracts are getting more popular by the day. Statista reports that sales of adult cannabis concentrate as of 2021 was about 3 billion dollars. This figure is estimated to go beyond 6.5 billion dollars by 2025.
The growth is all thanks to the legality around this plant getting clearer. Visit https://www.fda.gov/ to learn about the 2018 Farm Bill and how it relates to hemp production.
With the growth of this market, the demand for solvents used to extract the needed compounds from cannabis plants is equally growing. While many producers opt for CO2 and hydrocarbons, ethanol is still a preferred option for both high-throughput and small-scale producers.
Ethanol extraction offers several benefits; however, it also has some drawbacks that other extraction methods don’t have. Luckily, some of these drawbacks can be avoided by just adjusting the kind of extraction process used. For instance, warm ethanol processes offer a fuller profile; this is considered a beneficial factor for some cannabis-based products. Whereas, cold ethanol processes will reduce the number of unwanted compounds in the end product.
In this article, we will be considering the types of ethanol extraction and the benefits they offer. This way, you’d know which to opt for based on what you want at the end of the day.
Cannabis Ethanol Extraction Types
Deciding to make use of ethanol as your solvent for an extraction process is merely one of the choices you have to make. After this choice, you have to choose the exact process that suits your needs. Several options are available to you; these options are mainly different based on the ethanol temperature. Below is a summary of these types.
1. Cold and Room Temperature Ethanol Extraction
Both cold and room processes have similar basic steps. Both of them can be performed without the use of specialized equipment, the setup is also relatively simple. However, because the ethanol’s temperature for each process is different, these ethanol extraction processes provide different results. The following are the major steps involved in these processes:
- The cannabis plant is put in a vessel that is fit for this procedure. The plant may either be left like that or placed in a bag (like a very big teabag). The cannabis is then covered completely with the solvent. The time used to soak the plant in the solvent is often based on the desired product and the temperature used.
- During the soaking time, the cannabinoids and other compounds like plant lipids, pigments, and terpenes will be solubilized by the solvent. The compounds as well as their quantities are often based on the temperatures used and other factors including the plant part, raw material condition, and the plant’s strain.
- Once soaking is complete, the cannabis material will be removed from the solvent. If the material had been placed in a bag, then this step may involve simply taking out the bag. But if loose cannabis matter was used, then filtration has to be done.
- What is done next is often based on certain factors like the temperature used and the desired result of the product. For instance, for certain extracts, winterization has to be done to take out undesired lipids. Whereas, for certain extracts (especially when cold ethanol was used), the result is accepted the way it is.
- The next stage involves removing the solvent from the cannabis extract. Usually, this is done via vacuum distillation. However, for large-scale productions, falling film evaporators are used.
- Although the 5th step would have removed the solvent to an extent, an unwanted level of the solvent may still be present in the extract. So, the final step involves removing the residue left; vacuum ovens are usually used for this, but hotplate stirrers are also used.
Room temperature processes make it possible to get a full profile product without the use of cooling or heating equipment. The two major benefits of this method are the fuller profile achieved and the relatively cheaper equipment costs. Cold processes on the other hand have the advantage of not pulling out pigments and lipids.
2. Warm Ethanol Extraction
Hot or warm ethanol extraction usually involves the use of specialized equipment. A popular method used is Soxhlet extraction. Here, the cannabis raw material is put in the Soxhlet extractor, and then warm ethanol gets passed through the equipment several times. You can watch this video to learn more about this technique. Once this step is complete, some other steps like winterization will be carried out to remove the solvent.
This process makes it possible for an extractor to solubilize several compounds out of the cannabis plant. This makes it an ideal choice for full-spectrum extracts. However, due to the high temperatures, pigments like chlorophyll may also be extracted; these undesired pigments usually taste bitter. Sensitive compounds like terpenes can also be damaged and this will only impact the extract’s taste further.
Although undesired compounds can be removed, a lengthy process with several steps has to be done to achieve this.
Ethanol extraction is of different types based on the ethanol’s temperature. These types include warm/hot, cold, and room temperature processes. Each of these methods has its benefits as well as its drawbacks. So, none can be said to be better than the others. Therefore, the type you choose to use should be based on your budget and the desired product profile.