Cannabis extraction is the process of removing desirable compounds, such as CBD and THC, from the plant matrix. As the cannabis industry has grown, various extraction methods have been developed, each with their own advantages and disadvantages. In this article, we will discuss some of the most common and novel cannabis extraction techniques currently in use.
Solvent-based Extraction
Solvent-based extraction methods include Soxhlet, maceration (both static and dynamic), ultrasonic-assisted extraction, and microwave-assisted extraction. These methods require a solvent to complete the extraction process. Common solvents used for extracting cannabinoids include ethanol, butane, propane, hexane, petroleum ether, methyl tertbutyl ether, diethyl ether, carbon dioxide (CO2), and olive oil.
Solventless Extraction
Solventless extraction methods do not require the use of solvents. Some common solventless extraction techniques include:
- Hand-pressed Hash: One of the earliest forms of solventless concentrates, developed centuries ago, involves using hands to press and separate the resin from the plant.
- Rosin Press: A rosin press uses heat and pressure to extract cannabinoids and terpenes from the cannabis plant.
- Dry Sift: This method involves using a series of screens to separate trichomes from plant material.
- Bubble Hash: Using ice water and agitation, trichomes are separated from the plant material and collected using micron bags.
Static Glove Method
The static glove method is a simple technique to collect trichomes from the cannabis plant. It involves wearing gloves and gently rubbing the plant material, causing trichomes to stick to the gloves. This method is not as efficient as other methods but is a simple and accessible way to collect trichomes.
Cannabis Ice Water Extraction
Cannabis ice water extraction is a novel method that uses water as a solvent. In this technique, the plant matter is frozen right after being trimmed. The frozen marijuana material is then washed in cold water. Because cannabinoids are denser than water, the compounds can separate from the leaf material during the wash. After this, the cannabinoid-rich water only needs to be filtered through a series of micron bags before it’s ready to be used.
Ice water extraction is used to make kief, which can then be pressed into bubble hash. This method is one of the cleanest and safest ways to make high-quality, very pure hash with no adulterants. It also tends to leave behind many desirable cannabinoids that other methods don’t.
Conclusion
Based on current knowledge, using organic solvents is the most convenient method for medicinal cannabis extraction. However, more research is needed for some of the drying and extraction methods. Developing a green and sustainable cannabis extraction method should be considered for future studies. As the cannabis industry continues to grow, further advancements in extraction techniques are likely to emerge, providing even more efficient and sustainable methods for obtaining the valuable compounds found in cannabis plants.