What Are Terpenes?

As the cannabis industry matures, so does the research on the health benefits offered by the plant’s two well-known cannabinoids: Δ⁹-tetrahydrocannabinol (THC) and cannabidiol (CBD). However, research on terpenes, the lesser-known but equally vital chemical compounds of cannabis, has only just begun. These naturally occurring hydrocarbons are abundant in cannabis trichomes, adding unique qualities and benefits to the plant’s effects as they work together in the human endocannabinoid system with THC, CBD and lesser-known cannabinoids, CBC, CBG, CBN, and their acidic forms: THCA, CBDA, CBCA, CBGA, and others.

Terpenes and Their Effects

Terpenes are aromatic oils secreted by most plants. They’re volatile molecules that evaporate easily, each with a unique scent and flavor. These plant components are responsible for many of nature’s fragrances, and flavorings—the air in a pine forest, the citrus aroma of lemons and oranges and the bitter, peppery taste contributed to beer by hops, for example.

Likewise, terpenes provide the spectrum of scents and flavors in cannabis. They’re highly concentrated within the plant and can vary across strains. For example, strains such as Pineapple Express and Strawberry Cough contain mixtures of terpenes that give them a “fruity” flavor, while those like Thin Mint GSC and Alaskan Ice carry a minty taste with hints of spice and herbs. Over a hundred known terpenes have been found in cannabis, and yet thousands more are still undiscovered.

Research has found that terpenes work collectively with THC, CBD, and other cannabinoids (meaning the whole plant) to heighten the effects of cannabis in the human endocannabinoid system. Dubbed the “entourage effect,” terpenes’ ability to work in harmony with other cannabinoids means they’re a vital part of the cannabis plant profile. Each strain’s full medical and recreational benefits are enhanced differently by the individual terpenes present.

Common Terpenes and Their Effects

Each terpene comes with its own profile of flavor, scent, and unique effects. Terpenes, which are not controlled substances and derived from many different types of botanicals, have been studied for decades, and much of this research shows promise for scientific proof of various terpenes’ effects.

Here are the four most common terpenes found in cannabis today:

• Myrcene. This terpene comprises over 20 percent of the total terpenes found in cannabis, and 40 percent of cannabis strains are dominant in myrcene. Also found in hops, offering a peppery, bitter taste to beer, and in lemongrass, a medicinal herb. Traditionally, myrcene has been used as an anti-inflammatory and to induce a sleepy, relaxed state, but research has yet to confirm these effects. Animal studies have shown myrcene to have muscle-relaxing qualities, but no evidence has yet confirmed this effect in humans. 
• Limonene. This is the second most abundant terpene found in cannabis. Known for its citrus smell, limonene is also plentiful in cosmetics and cleaning products. Research thus far suggests limonene may elevate mood, eliminate stress, and have antibacterial and antifungal properties. Evidence also points toward limonene’s anti-tumor effects.
• Linalool. Linalool has a lavender scent with a hint of spiciness and is found in over 200 types of plants. This terpene is a proven anti-microbial and reduces levels of anxiety and depression. Other potential benefits of linalool include muscle relaxing and pain-relieving qualities, and possibly Alzheimer’s Disease help.
• Pinene. Pinene is a catch-all term for both the alpha-pinene and beta-pinene terpenes. These two closely related substances produce piney scents and initially emerged as a protective substance for plants. Besides cannabis, pinene is present in conifer trees, orange peels, and parsley. More research is necessary, but studies claim that pinene promotes anti-inflammatory properties, acts as a bronchodilator, and helps combat short-term memory impairment associated with THC use.

Cultivating for Terpenes

Selective breeding can combine terpenes in infinite ways, creating strains ranging in aroma from woody to floral to citrus. As more research and experience with terpenes emerges, there’s no doubt that more designer-flavored strains will appear. For the recreational market, terpenes can be honed to produce appealing flavors and scents. For the medical market, terpenes can be chosen, intensified, or isolated based on desired medicinal effects.

As more science emerges, more cannabis users are selecting strains based on their terpene profiles rather than just their THC and CBD (and another cannabinoid) content. The cannabis market is catching on to the role of terpenes quickly, which makes now a good time for those in the industry to learn about selective breeding for terpenes.

Development in cannabis gene-mapping will improve breeding, allowing breeders to select particular terpenes and pinpoint specific desired cannabis traits. By identifying terpene genes, breeders can fast-forward the time it takes to breed selectively for traits. A comprehensive cannabis gene map will make it much faster and easier to generate terpene-specific strains.

It’s also becoming standard practice that cannabis products include a terpene breakdown, analyzing the amount of the highest-occurring terpenes in the product. Many legalized cannabis states now require the full profile of terpenes to be printed on the labels of cannabis products.

The Future of Terpenes

The future of terpenes begins now. New methods of testing cannabis for terpene identity and strength are being developed, meaning maximization of terpene potency and diversity are on the horizon. More technology specializing in terpene measurement and selection will surely make its way to the market as research provides more answers. Although terpenes were discovered in the late 1800s, the cannabis industry didn’t understand their essential role medicinally until very recently. While consumers tend to concentrate on cannabinoids, growers pay an equal amount of attention to terpenes.