How can you extract sensitive cannabis terpenes to make your products stand out?
Medicinal Use of Cannabis Terpene Extraction
When it comes to discussion on terpene extraction, we must start with the trichome. Cannabis buds are covered in glandular trichomes that produce resins the contain cannabinoids like THC and CBD, and terpenes. A plant's terpenes are part of what give it its unique characteristics like smell and taste. CBD and THC aren’t the only "active ingredients" in cannabis. There are over 100 terpenoid compounds in cannabis, many with bioactive properties that contribute to the overall effects of cannabis through the "entourage effect". Terpenes can influence the medicinal qualities of cannabis and work in synergy with cannabinoids to improve their therapeutic effects. Terpenes are thought to contribute to the anti-anxiety, anti-inflammatory, antibacterial, and sedative effects of cannabis. Terpene-only supplements are becoming an interest since they also have medicinal properties of their own and can act on the endocannabinoid system without the help of THC or CBD.
If you come across an unknown term within this article, we've got you covered! We suggest that you keep our Glossary of Cannabis Terms and Terminology open in a new tab for quick reference.
Properties of Cannabis Terpenes
Terpenes, and terpenoids derived from them, are a key ingredient in essential oils of plants and flowers. Plant genetics, soil nutrients, plant stress, light, and heat are major factors that can alter or degrade a plant’s terpene profile. Unlike the cannabinoid profile of a cannabis plant, the terpene profile is not genetically stable through strains and can change depending on how the plant is grown. There are 17 dominant terpenoids that are used to classify cannabis according to its biochemical composition.
There are over 100 terpenoid compounds in cannabis, many with bioactive properties that contribute to the overall effects of cannabis through the “entourage effect”.
Major Cannabis Terpene Effects
Myrcene is found in bay, cannabis, ylang-ylang, wild thyme, parsley, cardamom, and hops. Myrcene has a pleasant scent and has been associated with anti-inflammatory, analgesic, sedative, and antibiotic effects. It is also thought to prevent cell mutations.
Ocimene has a sweet herbal scent and antifungal properties, but is also associated with coughing from smoking cannabis. Ocimene may contribute to the energizing feeling some cannabis strains have. It has a sweet, fragrant, herbaceous, and woodsy aroma, and is also found in mint, parsley, pepper, basil, mangoes, orchids, and kumquats.
Limonene has a distinctly strong citrus aroma and is found in many citrus fruit peels, and is often found in uplifting sativa strains of cannabis. It has a long history of medical use and has demonstrated effects like mood elevation, stress relief, antibacterial and antifungal action, and relief from digestive stress like heartburn and acid reflux. Limonene assists with the absorption of other cannabis terpenes, especially with topical and digestive absorption.
Pinene is a terpene that may help counteract the psychoactive and paranoia effects of THC. Pinene has an alpha and beta form, with alpha-pinene being the most abundant in cannabis and many other plants. Pinene can be found in plants like pine trees, rosemary, dill, basil, and parsley. In cannabis, it is thought to contribute to alertness and focus, and contribute to anti-inflammatory activity.
Caryophyllene is a terpene that can interact with CB2 cannabinoid receptors. Caryophyllene is thought to have anti-inflammatory, analgesic, anti-anxiety, anti-depressant, and anti-cancer effects. It may also play a role in reducing cravings for alcohol. Caryophyllene is often a major terpene of kush strains of cannabis, and is also found in clove, basil, oregano, lavender, rosemary, ylang-ylang, and hops.
Humulene is a cannabis terpene that can suppress appetite, and have antibacterial, anti-inflammatory, and anti-tumor effects. It has a slightly earthy or musky scent with spicy undertones and is also found in hops, sage, ginger and ginseng.
Terpinolene has a fresh, piney, floral, herbal, and sometimes citrusy scent and flavor. Nutmeg, tea tree, conifers, apples, cumin, and lilacs, also contain terpinolene. In cannabis, terpinolene is found most commonly in sativa-dominant strains. Terpinolene had many medical properties such as anticancer, antioxidant, antibacterial, and sedative effects.
Decarboxylation Destroys Terpenes
The main problem with utilizing cannabis terpenes for medicinal benefits is that they degrade quickly when the buds are heated. In order to convert THCA and CBDA into usable THC and CBD, cannabis buds have to be decarboxylated through heat. For preparing CBD oil, this can be done using an oven or by heating dry herb in a hot water bath. Conventional oven drying methods will destroy almost all terpenes, and 50% of a bud’s terpenes will be destroyed in just 5 minutes in a hot water bath.
Terpene Degradation During CBD Oil Extraction
The CBD oil extraction process is often done by solvent extraction. Extraction solvents along with heat can break down terpenes. One approach to solve this problem is to extract the terpenes first, then perform cannabinoid extraction. After both extractions are complete, they can be re-combined to create a full spectrum CBD oil that includes terpenes.
Cannabis Extraction Methods that Preserve Terpenes
Vacuum-drying ovens and carbon dioxide extractors are the two main methods full spectrum CBD oil producers are using to preserve terpenes. Vacuum-drying ovens can be used to isolate cannabis terpenes in an extract. These ovens remove a solution of water, solvent, and terpenes from the cannabis bud. That solution can be separated by filtration to purify terpenes, purified, then added back to the cannabinoid extract.
Supercritical Carbon Dioxide Method
Supercritical carbon dioxide (SC-CO2) extraction is another method that helps retain terpenes in CBD extracts. Supercritical carbon dioxide is both a liquid and a gas because of the temperature and pressure conditions used to keep it in an intermediate state. This high tech extraction method is very popular because it produces very clean cannabis extract without solvent residues that can be left behind. SC-CO2 extraction can enhance potency of cannabinoids and terpenes, so the extract of a plant may have different characteristics than the starting plant material.
CO2 extraction is good for preserving terpenes because it is a cold separation process that can protect delicate plant compounds. A short, light run of a SC-CO2 extractor is called a subcritical run. This short cycle can be run prior to a supercritical cycle to extract terpenes. Some methods may also use ethanol to help remove terpenes before fully extracting cannabis buds.
Winterization to Finish the Extraction Process
After terpenes are extracted, they are winterized. Winterizing extracts uses alcohol and freezing to separate pure cannabinoids and terpenes from other extraction byproducts. Carbon filtration can also be used to refine extracts and remove chlorophyll, which has a bad taste. After extracts are winterized, any remaining solvents can be removed through short path distillation or by using a rotary evaporator to boil off any remaining alcohol in the extract.
The main problem with utilizing cannabis terpenes for medicinal benefits is that they degrade quickly when the buds are heated.
Terpene extraction is an interesting tool in the arsenal of the knowledgeable grower. The process can be complicated however, which is why it's so important to thoroughly plan your operations. For more information, and actionable tips from our Master Grower on how to improve your yields and processes, please visit our Seed for Success program.
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