terpene extraction header

Mastering Terpene Extraction: At Home and in the Lab

by | Jun 19, 2020

terpene extraction header
Detroiter Karhlyle Fletcher is the host of High Lit, a cannabis research and classic literature podcast featuring leading voices and independent music. In addition to years in written and video cannabis journalism, he is also a traditional author.

As the cannabis industry grows to include even a pharmacological space, understanding cannabis compounds only becomes more critical. Terpenes, ranging from the atypical cannabinoid caryophyllene to the stimulating pinene, help define the cannabis experience. 

Why Are Terpenes Important? 

While there is no correct method of cannabis consumption, there are different philosophies. On the one hand, people believe in isolates, such as pure CBD, and on the other hand, people believe in full-spectrum products, such as natural herb. However, the industry shows that in a world of vapes, tinctures, and other extracts, the middle of the road is often the sweet spot. 

Products enriched with strain-specific cannabis-derived terpenes do the best at maintaining the original essence of a strain. With hundreds of cannabinoids and terpenes naturally occurring in any given flower, there’s no way yet to reverse engineer a strain profile with an isolate. However, even without perfect profiles, adding cannabis terpenes widens the spectrum of a cannabis isolate and creates a more genuine experience in regards to the entourage effect

full spectrum high terpene extraction, on tweezers on a orange background
High cannabinoid full spectrum extractions are slowly getting displaced by the demand for terpene forward extractions.

Terpene Extraction: Using Steam At-Home

As a natural field of study, chemistry has humble roots. While now science is advanced enough to separate stem cells, before burning substances to uncover their ash or “body” was a part of science. Currently, spagyrics are a niche practice, but before, they were the mainstream. 

Science was once called alchemy, and the equipment was relatively simple. To perform the steam extraction of essential plant compounds, put a container with water on burner, and feed the steam into a plant material flask. The steam should then go into a condenser tube where it can become a hydrosol mixture. That mixture is water and terpenes. Remove the water, and there are the cannabis-derived terpenes. 

While this method is full of a whimsical aesthetic that works in a garage, steam extraction is notoriously ineffective. Not only is the heat so hot it damages certain cannabis compounds, but other compounds remain unharvested throughout the process. For the best results, grind the flower to increase the affected surface area. Steam extraction is an excellent addition to a personal workshop, but far less tempting for more extensive operations. 

Are There Better Options for Commercial Production? 

While terpenes are a natural part of life, present in pine trees, pepper, and even some mammals, they’re very fragile compounds. When heat, stress, and other factors can easily disturb terpenes, effective extraction methods have to be delicate. Due to this, most commercial extraction methods end up relying on a light hydrocarbon extraction method, such as propane or butane.

Additional strategies for increasing terpene yield is using cannabis that is at peak terpene content, either through freshly harvesting it, or flash freezing the material. Throughout the hydrocarbon extraction method, the variety of cannabis terpenes attach to the mixture resulting in a saucy soup. The hydrocarbon can be burned off of this mixture at incredibly low temperatures, preserving the terpene content while removing the solvent such as propane or butane. 

After this extraction, the solution can be further purified; however, the terpene mixture is already potent and viable. 

What Are Botanical Terpenes? 

While cannabis is a botanical material, botanical terpenes refer to terpenes taken from other plants. For example, conifer trees are one of the most abundant sources of terpenes within the natural world.

Legal limitations, such as some state’s restriction on introducing non-cannabis derived terpene extractions into cannabis products, make these terpenes not as relevant to the industry as they could be. Additionally, the natural terpene profile of cannabis strains exists for a reason, and adding in botanical terpenes may not have the same balanced effect as relying on substances from the cannabis plant. 

Innovative Terpene Extraction Solutions Are Developing

Less than a year ago, Milestone displayed their ETHOS X. This device is capable of terpene extraction without the use of any solvent. Through utilizing microwave technology, they can use the water in the plant itself and its evaporation to harvest the terpenes. They claim their device is more energy-efficient and more precise. The precision allows the ETHOS X to specifically target terpenes, and end up with a pure extract of the compounds.

As with anything, the correct method comes down to preference and availability. Steam extraction is perfectly fine for the home grower, trying to explore their terpene profiles. It’s an excellent way to review cultivars and see what’s going on under the leaf. However, commercial operations are better off with something more consistently substantial, whether that be through using a hydrocarbon or another experimental method. 

Still, some states even allow the use of botanical terpene extractions and so there’s little that holds true across the board. When considering how best to extract terpenes, consider your ability to invest, the overall size of your operation, and what you believe best preserves the experience of consuming cannabis.