Extraction techniques are employed to separate the components of cannabis and remove them from the plant matrix. Various methods can divide cannabis plant material into parts, or extracts, that have different chemicals. With cannabis, extraction techniques are often used to isolate specific desirable compounds, and cannabis contains at least 113 cannabinoids, including cannabidiol (CBD) and tetrahydrocannabinol (THC). On the other hand, a producer may seek to create a single extract with lots of desirable cannabis compounds; sometimes called whole plant extracts. Such as the better-known cannabinoids, scientists have identified more than 550 chemicals in cannabis in general including components like terpenes. Extraction techniques are also utilized to concentrate chemicals of interest.
This post goes over the most frequent methods of cannabis extraction. Before discussing these methods, readers need to keep in mind that cannabis extraction is chemistry, not cooking. So, some skills in analytical methods plus real lab equipment must perform these techniques correctly and safely. Most of the time, the reagents and how they are utilized can create dangerous situations. Consequently, most of the techniques require safety equipment, like a fume hood. Just as vital, the extraction process must be performed correctly to generate a safe product for human use, and also the results needs to be confirmed independently with proper analytical testing.
Cannabis alcohol extraction – Several common types of cannabis extraction count on a solvent, including alcohol. In brief, the cannabis soaks in alcohol, usually ethanol, the plant material is then removed, the liquid filtered, and the alcohol is taken away with some form of evaporation. One of the biggest challenges is the inherent polarity of solvents like ethanol-meaning it features a propensity to combine with water and dissolve water-soluble molecules like chlorophyll. Eliminating the chlorophyll through the extract is essential since it produces an undesirable, bitter flavor.
This process can be practiced at atmospheric pressure, but the temperature is carefully controlled, especially during evaporation. This process can also take some time and must be done carefully in order to avoid danger as ethanol is extremely inflammable. One of the primary benefits of this kind of extraction is the fact there is not any probability of leaving toxic residual chemicals within the final cannabis extract and, it enables the co-extraction of all the compounds of interest, chiefly cannabinoids and terpenoids.
CO2 cannabis extraction – Utilizing a reagent of the kind can add cost and clean-up time, so various techniques should be considered, then one is CO2 extraction. As opposed to using alcohol, this process removes cannabis components vrpmen the plant matrix with fractional co2. Here, though, high pressure and also heat are utilized to turn the CO2 supercritical-meaning it is simultaneously like a liquid as well as a gas.
The equipment cost for this particular method is orders of magnitude more than alcohol extraction, but it produces higher yields and much less valuable material is lost. Plus, this process can be adjusted to extract specific compounds by changing the temperature, pressure or runtime-more likely a mix of these. Moreover, one study found that different compounds get concentrated at different rates in the same process. So, the extract needs to be analyzed, especially where concentrations of specific compounds are desired.