In recent years, a rising trend amongst cannabis consumers, both recreational and medicinal, has been the use of cannabis extracts. However, as consumers and patients become more sophisticated in their purchasing habits, so too do their expectations. Market demand has leaned towards a cleaner and more consistent extract, and one extraction method that has answered the demand uses supercritical CO2 (SC-CO2). The use of SC-CO2 as an extraction solvent has risen over the past few decades in various other industries, such as essential-oil extraction and coffee decaffeination. As for cannabis, SC-CO2 extracts are increasing in popularity since they are both cleaner and safer than organic-solvent-based extracts.
The SC-CO2 Method
Carbon dioxide (CO2) becomes a supercritical fluid when the temperature and pressure of the CO2 pass a critical point; 1071 psi and 87.98 F. At this point, the fluid can dissolve solutes but also diffuse like a vapor through solids. Extracts using the SC-CO2 method are made by passing fluid, or SC-CO2, through cannabis tissues at high pressure, then reducing the pressure to separate the extract from the CO2. Depending on the temperature, pressure, and duration of each extraction run, the resulting extract can vary in color, viscosity, and content of cannabinoids and terpenes. Many extracts are then further processed to produce an extensive variety of products available to the market today.
Cannabis oil creation and use
Oil, the liquid form of a CO2 extract, can be consumed in a multitude of ways; it can be smoked, vaporized, or ingested after being further processed into edibles. Before use, though not always, the oil is separated from the waxes and lipids that remain in the extract. The most common separation method, winterization, is the process of dissolving the extract in ethanol then freezing the mixture, which allows the undesirable components to precipitate, or separate, out of the mixture. The ethanol contained in the remaining extract is then removed via distillation, and the finished oil usually contains anywhere between 45-80% cannabinoids. Manufacturers can make oils containing less wax and lipids by using subcritical extraction methods, thus diminishing the need for winterization.
Vaporizing through the use of a vaporizer or vape pen is a popular method of oil consumption due to its convenience, cleanliness, and discretion. Vape pens, which come in both disposable and reusable variants, are typically filled with 0.25 to 1.0 ml of oil and work differently based on the viscosity and content of the oil located within.
Distillation of cannabis oil offers a heightened purity, potency, and versatility to consumers. Distilling, a process of refinement, separates and isolates cannabinoids from other compounds within the oil. The result is the purest form of cannabis extract, strongly resembling honey in both color and consistency. Like oil, distillate can also be consumed in a variety of ways but, due to high viscosity, must be mixed with a carrier oil before use in a vaporizer pen.
Wax and Shatter
Wax, shatter, and crumble are highly concentrated cannabis products that can also be smoked or vaporized. Traditionally, these products were made using methods such as butane extraction, but manufacturers have recently shifted to alternate processes. Waxes and shatters are produced by first creating the desired consistency of oil through varying the extraction conditions, then using evaporation and/or mixing techniques to achieve the desired product form. Depending on the oil consistency and level of agitation provided, shatter, crumble, or wax is formed. It is important to note that crystalline extracts such as shatter require starting with non-decarboxylated cannabis, as THCA is what forms the crystalline structure on a molecular level.
Edibles are commonly made by mixing oil or distillate with an intermediate cooking product such as fat, olive oil, butter, coconut oil, avocado oil, honey, or syrups or glycerin, to be then added to the desired end product. In mixing the cannabis oil with fat, consumption will transport cannabinoids to - and be broken down by - the body’s lipid metabolizing system, resulting in the “body high” that so often assists with pain relief and other such conditions.
Prior to the production of edibles such as cookies, brownies, or gummies, manufacturers first decarboxylate, or heat, their oil or flower to activate the cannabinoids within. THC-acid or THCA, the precursor to THC, is a non-psychoactive cannabinoid with poorly understood therapeutic effects. THCA must be heated, or decarboxylated, to approximately 105 °C (220 °F) under ambient pressure to turn it into its psychoactive successor THC.
Cannabis oil can also be deposited into capsules or tinctures for easy and precise consumption. Capsules are available in various potencies depending on the amount of carrier oil used and allow for an accurate and discrete form of consumption. Traditionally, a tincture is made by dissolving oil in ethanol, with the potency of cannabinoids such as CBD extracted dependent upon alcohol content. Finished tinctures are placed in vials with droppers, allowing for precise quantities to be placed under the tongue.
When applied topically, the effects of analgesic and anti-inflammatory cannabinoids, such as CBD, are apparent. Essentially, cannabis-infused topicals are made by mixing cannabis oil, cooking oil (such as coconut oil), and wax together with heat. Because psychoactive cannabinoids are not needed for the medicinal efficacy of topicals, decarboxylation is not required.
CBD suppositories infuse fat (vegetable oil, olive oil, or coconut oil) with cannabis oil. As with edibles, the THCA must be first decarboxylated to produce a psychoactive effect. Cannabis suppositories are known for their quick onset and remain a viable option for those who cannot ingest or inhale cannabis. Once inserted, cannabinoids are rapidly absorbed into the bloodstream as the suppository comes into direct contact with the intestinal wall. Suppositories are an efficient way of absorbing cannabinoids into the bloodstream.