Terpenes 101: ‘Reefine’ your knowledge of this increasingly trendy topic

This Sept. 11, 2018, file photo shows blankets of frost known as trichomes on a budding marijuana flower at an artisanal cannabis farm SLOgrown Genetics, the coastal mountain range of San Luis Obispo, Calif. Cannabis contains more than 200 currently known terpenoids and can represent up to 10 percent of trichome content. (AP Photo/Richard Vogel,File)

Why are terpene profiles becoming inceasingly popular amongst cannabis producers and marketers? Science writer and cannabis expert Salina May explains.

The fact that more and more producers are adding terpene profiles when marketing their cannabis products is a welcome move for discerning consumers. Most cannabis consumers are probably at least somewhat familiar with THC and CBD cannabinoid contents and ratios and how they affect our bodies and minds, but fewer are aware of the scores of other cannabinoids and terpenes that are in cannabis products in varying amounts, depending on the strain and processing of the product.

Although terpenes have been long overlooked in scientific research and popular culture, they are rapidly becoming trendy in both, inevitably entering the world of cannabis marketing.

A number of cannabis producers, such as the Canadian company blkmkt, have begun publicizing the terpene profiles for the cannabis strains that they produce, in addition to the usual THC and CBD content and strain lineage.

But first, what are terpenes? They’re aromatic compounds found in many plants and foods, that give scent and flavour to the plant such as berry, citrus, or pine.

Read also: Terpenes: A non-technical discussion

In fact, in Pennsylvania and some other states, producers are required by law to disclose terpene profiles on product labels. This is likely to become even more common as cannabis legalization grows and stabilizes. By having terpene information available, a consumer can review and compare strains to find their individual desired effects. For example, their Alien Sinmint Cookies strain contains high levels of β-pinene (29%) as well as smaller amounts of limonene (16%), 3-carene (15%), and β-caryophyllene (7%), while their Cherry Punch strain’s dominant terpene by percentage is limonene (26%), followed by β-pinene (17%) and α-pinene (12%). While this may appear to be gibberish to those unfamiliar with terpenes and their effects, with a bit of internet research, this can be useful information for consumers in deciding which cannabis product is best for them.

A pioneer of cannabis research, Dr. Ethan Russo, published in the British Journal of Pharmacology his landmark 2011 paper, “Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects” which explored the therapeutic benefits of terpenes and terpenoids. (Terminology note: these words are often conversationally used interchangeably, although technically terpenes are a group of monocyclic hydrocarbons and terpenoids are terpenes that contain additional functional groups such as esters and alcohols in their chemical structure).

In the paper, Dr. Russo points out that terpenoids are flavour and fragrance components responsible for the aroma of cannabis as well as being commonly found in human diets, and are quite potent, affecting human and animal behaviour when inhaled in even very small amounts in the ambient air. These can be used for therapeutic effects as part of the larger “entourage effects” of cannabis and cannabis-based extracts. Entourage effects are the synergistic effects of combined cannabinoids and terpenes, which are different than and offer greater therapeutic benefits than each cannabinoid and terpene individually.

Cannabis contains more than 200 currently known terpenoids and can represent up to 10 percent of trichome content, according to Dr. Russo, with each having their own therapeutic effects. For example, a common cannabis terpene, limonene, has anti-anxiety and immunostimulant properties that have been demonstrated in humans, and another common terpene, β-myrcene has analgesic (pain relieving), sedative, and inflammation-blocking properties. Dr. Russo’s paper also suggests the synergistic cannabinoids that enhance these properties for each terpene. For example, with the terpene α-pinene, its anti-inflammatory effects have a synergistic enhancement with the cannabinoid CBD, while the opening of bronchial air passages are synergistically enhanced by THC. α-pinene also has properties that can aid memory function, which has synergistic effects with CBD and possible synergistic effects with THC, but more studies are needed to determine if this is true. One of the problems with reviewing terpene profiles for individual cannabis strains is that it can take a lot of research and quickly become highly complicated. With the current state of available information and consumer willingness to deep-dive into the research, it may be best to simplify by just looking at the main effects of each terpene, and try out strains containing those to see if they produce the desired effects. There are many useful charts and information sources for terpene effects on the internet, and a particularly good source is CannaInsider, which has a “terpene mood finder” where a consumer can input various effects they are looking for (happiness, anti-inflammatory, sleep, etc.) to find the terpene and examples strains containing high amounts of that terpene that match their desired effects.

Critics of terpene profiles point out a few potential deficiencies in the presentation of the information. One is that producers may want to cherry-pick which terpenes they add to the product profile and which ones they don’t want to advertise. For example, terpinolene, a terpene found in many strains such as Jack Herer, is believed to enhance anxiety rather than relieve it, so cannabis producers may choose not to add that terpene to a strain’s profile even if it is presen.

Another criticism of terpene profiles is that they do not account for cannabinoids such as CBG (cannabigerol) and THCV (tetrahydrocannabivarin) that can also have significant therapeutic effects as well as influence the overall entourage effects, and so not including these can obscure the big picture of effects of a strain.

Finally, as Dr. Ethan Russo points out in the “Taming THC” paper, terpenes can be negatively impacted by gamma radiation, which is a common method of sterilizing coliform bacteria in cannabis production in Canada. For example, gamma radiation has shown to reduce the terpene linalool in cilantro, and to reduce the terpenes myrcene and linalool in orange juice, and so is likely to also reduce terpene contents in cannabis, begging the question of whether the terpene testing is done on cannabis products before or after irradiation. It is worth noting that although gamma radiation, which was originally developed for use on food products, is widely used in Canadian cannabis, Dr. Russo points out that the safety of the technique for smoked or inhaled products has not yet been adequately tested.

Ultimately, more information is better than less information for those who want to be informed consumers, and the trend of publishing terpene profiles is a welcome one. For those looking for a peppy sativa, they may wish to try strains that are higher in α-pinene, then to have a strain higher in myrcene or linalool with sedative properties before they go to bed. Although terpene profiles and cannabinoids and the entourage effect can be complex and intimidating, terpene information can be valuable and point consumers in the right direction when they are looking to find the strains that work best for them.