For many of us, the thought of cannabis will likely conjure up a very distinctive and recognisable scent – that pungent aroma has become a tell-tale sign of nearby cannabis use that is almost unmistakable. And yet, the more seasoned consumer may be able to differentiate between different cannabis strains using only their nose. Like a sommelier picking out the various notes of a fine wine, a cannasseur may well distinguish various aromas undulating beneath the surface of the cannabis smell.
That’s because the smells of the natural world are usually far from unique to each plant species. In fact, a huge proportion of plants owe much of their pungency to the same group of compounds: terpenes.
Terpenes are present in most plants, from flowers to fruits and vegetables. They play a key role in the survival of plants by helping to make them attractive to pollinators and repulsive to predators. But they can also contribute to the flavours associated with different plants – including cannabis. We’re going to be taking a closer look at these interesting little compounds to get a grip on the science behind the “cannabis smell”.
A unique aroma?
Beer drinkers out there may recall carelessly sniffing the bottle of their favourite beverage and noticing that familiar scent. This isn’t just a coincidence. In actual fact, cannabis and hops, which are used to make beer, come from the same family – Cannabaceae. As relatives, these plants share a number of similarities, from their appearance to their terpene content. Some say this is why cannabis users tend to prefer a particularly hoppy IPA… (we couldn’t possibly comment).
The potential of terpenes
Terpenes are found in the trichomes (the sticky glands that cover the buds, leaves, and sometimes stems) of female cannabis plants. As we mentioned earlier, these compounds do far more than give cannabis its infamous pungent aroma; some, like geraniol, repel insects or herbivores that could potentially cause damage to the plant. On the other hand, other terpenes (like terpinolene and linalool) have been found to attract pollinators. But their usefulness doesn’t end there.
For millennia, doctors, spiritualists, and the average Joe have all been well aware of the therapeutic potential of cannabis. It is only in more recent times that we have begun to understand exactly what makes cannabis so useful for so many things. Yes, THC and CBD have been found to have significant medicinal potential, but researchers have also documented some impressive therapeutic properties in terpenes.
It is likely that terpenes contribute to the potential of many medicinal plants – a theory supported by their significant prevalence in many noticeable natural medicines. Furthermore, some research suggests that they may even help to boost the medicinal effects of other compounds, including cannabinoids. This is known as the Entourage Effect. While more studies are needed to build clear scientific evidence around this theory, scientists have long accepted the stand-alone potential of many terpenes.
Despite having a significant bearing on the scent, flavour, and possibly the effects of different cannabis strains, consumers in most jurisdictions are unaware of the terpene content of their products. In countries where access to cannabis relies only on the illicit market, this is largely down to a lack of regulation, testing, and informative packaging. However, many products in cannabis legal jurisdictions also fail to highlight the terpene content to their users.
So, let’s take a look at how terpenes can influence the aroma of cannabis and highlight some of their potential therapeutic properties.
Common cannabis smells
Earthy – Many cannabis strains can have an unmistakably earthy aroma that comes down to a number of terpenes, including myrcene, ocimene, and humulene. In fact, myrcene is the most common terpene found in North American and European cannabis varieties.
Floral – Ocimene also contributes to the floral scent of some cannabis strains, alongside linalool which is most associated with the intensely floral smell of Lavender.
Citrussy – We are all familiar with the fresh and fragrant scent of citrus fruits like lemons, limes, and oranges. These fruits all contain high levels of limonene, which is also a secondary terpene in many cannabis strains.
Skunky – Chances are you’ve heard some cannabis to be referred to as skunky. Until recently, it was believed terpenes were responsible for this unique cannabis aroma, but a 2021 study found that prenylated volatile sulfur compounds (VSCs) were behind the skunk-like funk in some cannabis strains.
Gassy – Cannabis with gassy aromas have a strong smell similar to petrol and diesel thanks to the dominant terpene β-Caryophyllene working together with secondary terpenes myrcene and limonene to create a unique profile.
The most common cannabis terpenes
Different strains of cannabis contain a different combination of terpenes (and other compounds such as cannabinoids and flavonoids) which contribute to the varied effects, scent, flavour, and appearance of different plants. However, there are a few terpenes that are by far the most commonly occurring in cannabis. These include:
Myrcene has an earthy and spicy aroma that it lends to the cannabis plants in which it is present. Myrcene can also be found in lemongrass, verbena, and bay, as well as citrus fruits. The scent, flavour and therapeutic properties of this compound have made it a popular ingredient in the manufacture of many food and drink products, cosmetics, and detergents. However, some recent evidence suggests that β-myrcene may also pose a risk as a potential human carcinogen.
Potential therapeutic properties: analgesic (pain-relieving), sedative, antidiabetic, antioxidant, anti-inflammatory, antibacterial.
β-Caryophyllene is well-known for its spicy, peppery aroma and flavour, thanks to its prevalence in black pepper. But it can also be found in cloves, hops, rosemary, copaiba and, of course, cannabis. In fact, it was one of the first cannabis-derived compounds (after THC, CBD, and CBN) to be found to bind directly to endocannabinoid receptors.
Potential therapeutic properties: antioxidant, anti-inflammatory, and anticancer.
As its name might suggest, pinene can be found in abundance in the essential oils of pine trees and has a recognisably piney smell. While it is most commonly found in pine and other coniferous plants, it is also present in camphorweed and big sagebrush. Its popular scent has seen pinene added to a wide range of consumer products from perfumes and skincare to cleaning products. Various studies have also demonstrated pinene’s impressive therapeutic potential.
Potential therapeutic properties: antimicrobial, anticancer, anti-inflammatory, and antiallergic.
As we have already mentioned, limonene is most significantly found in the peel of citrus fruits, but also in juniper, rosemary, and peppermint. Its pleasant scent has made it a popular ingredient for perfumes, skincare, and cleaning products – for which its solvent properties come in handy, too! It also has a long list of potential health benefits…
Potential therapeutic properties: anti-inflammatory, antioxidant, antinociceptive, anticancer, antidiabetic, antihyperalgesic, antiviral, and gastroprotective
Another terpene that has become a staple in the fragrance and skincare industries, linalool has an intense and pleasant floral scent that can soften the often-unpleasant smell of some cannabis plants. It is found in abundance in lavender, coriander, bay, and sweet basil. Like many terpenes, studies have revealed that linalool has impressive potential as a therapeutic.
Potential therapeutic properties: sedative, antidepressant, anxiolytic (anxiety-relieving), immune potentiating, analgesic, and anticonvulsant.
Being informed about the terpene content of different cannabis strains can be a useful tool in selecting the not only the most appealing, but the most effective product for you. We all have our own tastes when it comes to cocktails, desserts, and any other kind of consumable; we can only hope that one day, we are able to access the information we need to likewise identify our favourite cannabis strain.