One of the earliest noted uses of extracted cannabis for medicinal use was in the early 1830s by renowned Irish physician Sir William Brooke O’Shaughnessy. His studies led him to believe that cannabis extracts could dramatically lessen stomach ailments of patients suffering from cholera. Scientists and other physicians ran with the idea and by the end of the 1800s cannabis extract was a common item sold by physicians and pharmacists to alleviate gastrointestinal problems and their side effects. Following the Marijuana Tax Act in 1937, marijuana as it was then being called, a term coined from the South American and Mexican immigrants who were noted as using cannabis frequently, became one of the most highly illegal and controlled substances in the US. Through the prohibition, few examples exist of cannabis extraction and research up until the early 70s and 80s, when author Michel Starks and Alchemist D. Gold wrote about the various cannabis concentrates oils, their extraction methods, and the translucent and ‘honey’ like qualities of the oils extracted via activated charcoal and alcohol
Types Of Cannabis Extraction
Extracted cannabis products account for nearly 70% of the cannabis currently being sold in the State of Oklahoma and their popularity continues to rise and new techniques, product ideas, and technology becomes available to help with the cannabis extraction process. Cannabis extraction boils down to two technical types, solventless and solvent, or three expanded categories, solventless, solvent, and solvent-free. Each of the extraction methods create extracts that are different and yet share one common goal – to maximize the amount of THC extracted from the cannabis flower.
Solventless extraction generally entails the use of a rosin press which, press dependent, can apply over 2 tons of force and reach temperatures from 0° up to a sweltering 450° fahrenheit. It’s this combination of heat and pressure that creates the sweet, sweet rosin that is dabbed as-is by concentrate lovers or utilized in the cannabis edibles, tinctures, and other products that you know and love. While the yields from solventless extraction tend to be lower, the main reason that it is pursued so fervently by the top cannabis producers in Oklahoma like Arcadia (pictured below) is the full-spectrum and pure nature of cannabis extracted without the aid of a solvent. It’s as pure a derivative of the cannabis flower as possible and retains much of the fats, lipids, cannabinoids, and terpenes that were present in the flower that was pressed
There are multiple methods of extracting with cannabis solvents, most popular among them are BHO (Butane Hash Oil) and PHO (Propane Hash Oil). As with nearly everything in the cannabis industry, the names are straight and to the point of what they are. BHO utilizes the solvent butane as the medium through which it extracts the cannabis oils from the flower and PHO utilizes propane instead. Both methods are incredibly similar and the solvent used really just comes down to the personal preference of the extraction facility itself. – While Solvent extraction does leave residual solvents, extractors like Dose based in Oklahoma City are able to remove nearly all of the solvents left after the extraction process through special filtration methods that are kept under lock and key by experienced producers as the in-house developed methods used are considered invaluable to the production of each cannabis extractors signature oil lines and distinguish the purity and flavors of their brands when compared to others.
During the extraction process, the natural terpenes from the cannabis plant as well as other outputs, namely the concentrates like wax, shatter, and budder that are both intentionally created and byproducts of the extraction process are created and stored in separate colanders to be packaged and sold alongside the cartridges and other products created from the oils.
Solvent-Free Or Solvent-Less Extraction:
Solvent-Free Extraction is the functional third category of extraction. While technically being considered a ‘solvent’ extraction method, with CO2 being the solvent used, the high-pressure nature of the Supercritical CO2 methods and the very nature of Supercritical CO2 extraction leave little to no residual solvents after, leading to the beloved marketing term used by CO2 extraction experts world-over, Solvent-Free or solvent-Less.
Supercritical CO2 begins the process with liquid CO2 entering into a cooling exchange to maintain its liquid form before entering into the incredibly high pressure pump. Once the pressurization begins (usually to 250-350 bars) the temperature is raised to 31°C to activate the CO2 to supercritical. That solvent is then used to extract the plant ingredients without denaturing it. From there, the CO2 is extracted first by gravity, then by decompression and being under drawn. Finally, the Co2 is extracted through centrifugal force, leaving the CO2 in a gas-state before being cooled back into a liquid.
No matter which extraction process your favorite edible or concentrate processor uses, the most important thing is always viewing the lab results to make sure that the THC, CBD, Total Cannabinoids, and the overall ‘health’ of the processed cannabis products that you’re using are accurate and within healthy levels. The best rule of thumb for general medical use is to find the full-spectrum varieties of processed goods and use those so that you benefit in total from every aspect of the cannabis plant.