Have you ever wondered why certain CBD flower strains captivate you with their aroma, while others don't tell you much? In this post, we tell you the science behind the unmistakable aroma of cannabis. You will discover that the assessment of aromas is more sensation than science, that higher concentration does not mean that it smells more like that substance, that each combination is unique, and many curiosities about the aromas of cannabis. * Cover photo: Display that you can find in our CBD Barcelona and CBD Madrid stores.
In short — what does weed smell like?
- Cannabis has an earthy, herbal base, with notes that vary by strain: citrus, sweet, floral, piney or skunky (diesel).
- That smell comes from terpenes and sulphur compounds, not from CBD or THC, since cannabinoids have no smell.
- A stronger smell does not mean more potency: judging cannabis aroma is as subjective as a wine tasting.
What does weed smell like?
Cannabis has an unmistakable smell: an earthy, herbal and slightly spicy base, topped with very different notes depending on the strain: citrus, sweet, fruity, floral, piney or skunky (diesel). That aroma is not fixed: it depends on the plant's genetics, its ripeness and, above all, on how the bud is dried and cured.
What does weed smell like when smoked?
When burned, the smell becomes more intense, sweeter and slightly burnt. The signature skunk smell sharpens with combustion —largely due to the sulphur compounds in the resin— and clings to clothes, hair and the room for quite a while. That is why smoked cannabis smells far more pungent than the bud in your hand.
What does dried and cured weed smell like?
In a dry, well-cured bud the aroma is cleaner, more concentrated and pleasant. Poor drying, on the other hand, leaves a smell of hay, damp or chlorophyll. In fact, a strong, well-defined smell is one of the signs of a good-quality bud, and it keeps better when you store it properly.
What about derivatives like hash? By concentrating the plant's resin, its aroma is more intense, spicy and long-lasting than the flower's; we explain it in depth in our hash guide.
What is cannabis aroma?
The aroma of cannabis is unmistakable and an essential part of the cannabis experience. As with wines or coffee, cannabis offers a wide range of aromas and nuances among the different varieties. From citrus, sweet, floral or fruity aromas, to earthy, spicy and diesel, the richness of cannabis is infinite.
Marijuana tastings are becoming as popular as wine tastings.
Cannabis experts and conoisseurs are increasingly interested in appreciating the range of aromas that each cannabis variety has to offer. At Cannactiva, we classify the aromas of our CBD flowers, and we can confirm that it is often not an easy task.
Terpenes: The compounds behind the smell of marijuana
The smell of marijuana is a complex symphony of chemical compounds, with terpenes being the main protagonists. Terpenes are found inside the trichomes of cannabis, in the resin, along with cannabinoids. However, cannabinoids, such as THC or CBD, have no odor.
Terpenes are the protagonists of the cannabis aroma, while cannabinoids such as THC or CBD have no odor.
Cannabis produces an extraordinary amount of terpenes. It is capable of producing the same terpenes as citrus fruits(limonene), pepper(beta-caryophyllene), pine(alpha and beta pinene, terpinolene), lavender(linalool), mango(myrcene) or chamomile(bisabolol), as examples. Its phytochemical richness is extraordinary.
Cannabis produces the same terpenes as a wide variety of other plants, such as pine, lemons, pepper, mango and lavender.
These compounds have much more impact than simply satisfying our sense of smell: terpenes evoke a range of sensations and effects in cannabis users, and can affect mood. From sedation to mood elevation to memory enhancement, the properties of these compounds are unique.
Although terpenes are the stars, they do not act alone: volatile sulphur compounds are mostly responsible for the characteristic skunk smell of many strains, especially when smoked. They explain why two plants with similar terpenes can smell very different.
Alongside terpenes and sulphur, flavonoids add subtler nuances to each strain's aroma and colour profile.
And beyond smell, terpenes also shape how we feel: discover the effects of cannabis terpenes.
Another interesting aspect of terpenes is how they influence the effect of cannabis. We know that these compounds are much more than aromas: they form a synergy with cannabinoids and modulate their effect, known as the cannabis entourage effect.
How are cannabis flavors classified?
The classification of cannabis aromas is more complex than it appears. While science gives us an idea of the compounds behind the aroma (mainly terpenes), human experience tells us something different.
Measurement of terpenes
Since the "boom" of terpenes, those dedicated to the study of these aromatic profiles proposed terpene analysis to classify the different strains and varieties according to their terpenoid profile. In fact, after the legalization of marijuana and the professionalization of the sector in the United States, we have seen how many dispensaries incorporate terpenoid analysis in their product files. But today we know that this method is not valid and can confuse rather than help.
"Odor scientist" Dr. Avery Gilbert, Ph.D. explains that terpene analysis is not sufficient to capture the essence of cannabis because of the complexity of odors, in which molecules interact with each other to produce combinations that result in unique aromas.
Scent cards: it's not that simple!
Although it might be thought that identifying the most abundant terpenes in a variety would give us an accurate description of its aroma, the reality is much more complex.
Each terpene has a unique relationship between its concentration and the intensity of its aroma. Moreover, when combined, they create aromatic profiles that are more than the mere sum of their parts.
Listing terpenes in order of abundance in cannabis does not tell us what something really smells like. When terpenes are mixed, the olfactory result is different from the individual smells of each terpene. In fact, perfumers study not only the primary aromas, but also their basic combinations (called "chords"), before creating a perfume.
That unique combination of terpenes is also behind the differences between Indica and Sativa.
The mysteries behind the aroma of cannabis
Another important factor is the scent detection threshold. Each terpene has a minimum concentration above which its aroma can be perceived. The concentration detectable by the human sense of smell is much lower than the level of terpenes that a gas chromatograph can detect.
The human sense of smell is capable of detecting terpenes in minute quantities, undetectable by machines.
Moreover, each terpene has a unique relationship between its concentration and odor intensity. Some terpenes have a much stronger odor intensity than others at the same concentration. In addition, small variations in concentration can result in large variations in odor dominance. This is why, Dr. Gilbert explains, small changes in a perfume can make it feel very different.
Therefore, it is extremely difficult to translate a chromatogram or terpene analysis into a specific cannabis aroma. We need the subjective appreciation to be able to really assess how cannabis smells!
Marijuana tastings
A subjective assessment or "smell test" is absolutely necessary to understand a scent. Only with a marijuana tasting is it possible to reveal the unique aromatic profiles of specific cannabis strains.
According to a scientific study (2) in which participants were asked to describe different cannabis strains according to their aroma, it appears that the aromatic profiles of cannabis can be grouped into two broad categoriesearthy, woody and grassy aromas, or citrus, sweet and penetrating or pungent aromas.
Interestingly, the study also found that varieties with citrus aromas were perceived as more potent and therefore had a higher estimated price, compared to strains with earthy aromas.
However, marijuana tastings are not a foolproof method either. Scent perception is not only a sensory experience, but is influenced by emotional, cultural and memory factors. Two people may describe the same scent differently due to their own experiences, memories and references.
In addition, it is possible that people who use cannabis perceive its aromas differently from those who do not.
A great way to train your nose is to taste and compare several strains at once: you can set up your own tasting with a CBD flower pack of fresh citrus, sweet and tropical, earthy kush or skunk floral varieties, grouped exactly by aroma family.
In conclusion...
The classification of cannabis aromas is a world apart. Not only is there an enormous wealth of aromatic compounds and possible combinations in cannabis, but there is also a dance between science and sensations that makes it difficult to establish a "universal" classification. But, at the same time, this subjectivity is what allows us to experience unique sensations with this plant.
We invite you to discover your favorite varieties with one of our packs. Discover the variety of aromas that cannabis has to offer!
Explore the full range of CBD flowers and find the aromas that suit you best.
Referencias y más información
- Avery Gilbert, Ph.D., Headspace Sensory, LLC. The Chemistry and Perception of Terpenes. Article in Terpenes & Testing Magazine, 2021. Available at: https://www.averygilbert.com/
- Gilbert AN, DiVerdi JA. Consumer perceptions of strain differences in Cannabis aroma. PLoS One. 2018 Feb 5;13(2):e0192247. doi: 10.1371/journal.pone.0192247. PMID: 29401526; PMCID: PMC5798829.
