What are the Best Extraction Methods to Maximize Cannabis Concentrate Yields?The debate over the most efficient extraction methods comes from two major market factors: consumer and product.
Cannabis is known to contain more than 100 cannabinoid isolates, including THC and CBD, in addition to essential oils and terpenes. The extraction method varies widely depending on the desired isolates or formulation and the intended product and function.
Ultimately, extraction methods can be divided into two camps, solvent-based and solventless (non-solvent-based).
Efficient Cannabis Extractions - Solvents or Solventless?
Solvent-based extraction methods employ chemical processes to separate cannabinoids from the target cannabis plant. The plant matter is introduced into a closed-loop system where the solvent is applied – often repeatedly. After removing the harmful compound byproducts, the resulting product is refined into a concentrated resin.
Solvent-based methods are best for achieving efficiency, replicability, and ease of scalability. Unfortunately, due to the presence of flammable substances during the extraction period, there's a higher risk of fire or explosion due to misuse. Therefore, extensive safety measures are essential to safe, solvent-based extraction.
Solvent-based methods include:
- Alcohol Extraction: Room temperature or chilled ethanol is washed over the plant to dissolve cannabinoids and terpenes. Then the ethanol evaporates, producing an ideal extract for distillates or isolate products.
- CO2: Carbon dioxide is heated to more than 87.8 degrees F forming a gaseous liquid, and washed over the cannabis buds, separating compounds like THC and CBD. Then the CO2 is evaporated and condensed into a liquid and often recycled.
- Hydrocarbons: Butane, propane or a mix of the two are heated to low temperatures to produce full-spectrum extracts rich with cannabinoids and terpenes.
- Vegetable oils: The cannabis plant material is heated, then soaked in vegetable oil (especially olive oil). An additional step may include a process of dynamic maceration where the plant matter is finely broken up to ensure full extraction integrity. The result is a cannabinoid-rich oil that processors can incorporate into edible products.
On the other hand, solventless extraction is a non-chemically based method in which physical or mechanical extraction is employed. High pressure, extreme temperatures, and/or water is applied to the Cannabis plant, which then releases oils to form the sticky concentrate, called rosin.
Solventless extraction is favored by producers and consumers concerned with natural and environmentally minded processes since no toxic inputs or byproducts are added or left behind. Additionally, the terpenes are left intact. Unfortunately, solventless extraction processes tend to be much more labor and energy-intensive than their solvent-based alternatives and require more infrastructure.
Solventless methods include:
- Ice water: Once cut, the raw plant is frozen, then washed, separating the cannabinoids from the leaf. Then the enriched water is filtered, yielding an incredibly pure and potent hash extract with a delicate flavor and aroma profile.
- Pressed: Low heat is applied to the raw pants material, then is pressed between plates to produce an incredibly potent rosin extract that can be used as a dab in edibles and topicals.
- Screened: Cannabis is dried, then beaten through a mesh screen or sieve, forcing the trichomes to separate froing a powdery Kief with up to 50% THC potency. The trichomes can then be pressed into hashish.
What’s Best? There's No Single Answer
Each extraction method has its advantages and disadvantages. But the main rule of thumb is to know the end product, whether it be a topical lotion, a THC-infused beverage, or a vape pen oil. Additionally, knowing the product consumer profile will help determine which extraction method encourages buyers to choose one product over a competitor using an alternative extraction method.
For health-conscious consumers, offering products rendered via solventless extraction methods locally can be a savvy business decision for small-scale producers. Contradictorily, a medical review from MDPI highlights solvent-based extraction methods as a standardized practice within the pharmaceutical arena, and thus, more likely to be aligned with federal and state-level regulations.
The solventless pressed method produces some of the most potent and versatile extractions available today. And whereas the solvent-based CO2 method is the fastest, it doesn’t produce nearly as many compounds as the hydrocarbon method. And while vegetable oils might a be a logical input for edibles, producers opting for this solvent-based method must also bear in mind that while the process yields an attractive green hue as well as more cannabinoids and terpenes than ethanol extraction, the shelf life is relatively short, and the oil maintains an unpleasant taste, which may require producers to add more ingredient inputs such as sugar or chocolate to balance the flavor profile if the end product is a packaged THC-infused dessert for example.
Solvent-based extraction methods are king when considering the overall efficiency, especially for large and up-scaling productions that value reliable quality outcomes. However, the demand for natural, solventless extracts shouldn’t be dismissed, especially for the more niche, local producers.
When selecting the best extraction method, 'consumer' and 'product' should always be at the top of mind. The most efficient method is the one that drives consumer demand.