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High-Tech Plants: A Guide to Cannabis Extraction Methods

If you barely recognize cannabis these days, join the club! With cannabis medicine taking all sorts of—no pun intended—high-tech forms like CBD oil, RSO and tablets, it’s a whole new world when it comes to one of nature’s oldest plant remedies.

But how do plants get transformed into such a bewildering array of formulations? Welcome to the fascinating world of cannabis extraction methods! From very ancient handmade approaches to techniques developed in strict laboratory conditions, here’s a survey of some of the most noteworthy ways cannabis researchers and producers are bringing the healing power of cannabis to an ever-wider audience.

Cannabis Extraction Methods: A Brief History

Believe it or not, we humans have relied on cannabis for roughly 5,000 years! As long ago as 2900 BCE, Chinese physicians were using cannabis to treat pain and inflammation, among many other conditions we’d readily recognize.

The first known cannabis extract—Hashish, or hash—shows up around 900 AD. Hash is made by removing and concentrating the gooey trichomes that coat the cannabis flower, often by manually rubbing cannabis flower or soaking it in ice water. While its popularity has faded with the introduction of newer and more potent cannabis extracts, it still occupies an important place in the history of cannabis extraction methods. We should note that the unpressed or “powdered” form of hash is called kief; it’s frequently added to cannabis flower to add potency and flavor.

Cannabis Extraction Methods: Modern Approaches

More recently, cannabis was extracted into the liquid tinctures and oral solutions that were sold in pharmacies all over the United States through the end of the 19th century. But the modern story of cannabis extracts really takes off in the 1990s, when the butane hash oil (BHO) technique gained popularity. While the process was risky—both due to the exposure to chemical solvents and the legal environment of the day—a series of refinements eventually led to the safe, effective, and widely accepted techniques used today.

CO2 Cannabis Extracts

While BHO extracts still have their place—especially among medical cannabis patients suffering from serious symptoms such as chronic pain and sleep disorders—they’ve largely been supplanted by CO2 extraction. CO2 extracts use solvents such as ethanol, butane or carbon dioxide to remove the cannabinoids and terpenes from the plant matter. Using careful and precise practices developed in the laboratory, these products are then carefully purged of solvents and any other impurities. If you’ve ever used a cannabis vape, there’s a good chance you were sampling a product made by CO2 extraction. Although it’s not as nuanced as some other extracts, it’s still a potent, effective and self-stable product.

Live Resin

When it comes to flavor, one of the most exciting developments in the cannabis extract world are the semi-solid products known as “live resins.” Made with flash-frozen cannabis flower as opposed to the dried and cured cannabis flower you’re probably familiar with, live resins contain an extremely high proportion of flavorful and aromatic terpenes. As a result, many people describe live resins as being nearly “hyperrealistic” in terms of their flavor profiles.

RSO

On the other end of the spectrum is RSO, short for “Rick Simpson Oil.” Invented by an amateur home chemist to treat his skin cancer, RSO is produced by extracting cannabinoids into a solvent such as isopropyl alcohol, then reducing the extract into a viscous oil with gentle heat. It can be taken orally or topically, and it’s known for its straightforward relief of medical users’ symptoms.

Cannabis Tablets and Capsules

Finally, you may even have heard of or tried cannabis tablets and capsules. While they’re produced by a number of different extraction methods, they typically combine a potent cannabis concentrate with an emulsifier such as soy lecithin to form a dense, consistent, and shelf-stable product.

Believe it or not, we’ve only scratched the surface when it comes to the world of cannabis extraction methods. Hopefully, this article gives you an idea of the various types of approaches enterprising cannabis producers have used to improve the potency and usefulness of this truly ancient plant medicine!

If you want to explore different consumption methods for yourself, check out our Minneapolis marijuana dispensary.