In Part 1 of our Science of Exotic anthology, we explain the revolutionary discovery of flavorants and their impact on cannabis aroma.
Cannabis science has come a long way over the last several decades. Most recently, we’ve discovered that when it comes to the aroma of exotic cannabis cultivars, the role of terpenes… may have been overemphasized.
Did you just hear the sound of a record scratch? Just us? That’s fine.
We get it. We talk a lot about terpenes. We have a LOT to say about their contributions to cannabis aroma, flavor, and effects… but we also have questions.
Like why do Dogwalker OG, Tropicana Cookies, and Purple Punch smell VERY different but also have similar terpene concentrations? What are the chemical origins of the exotic aromas that cannabis produces?
So, with help from 710 Labs, Markes International, and SepSolve Analytical, we set out to answer these questions. In doing so, we discovered entirely new classes of compounds that distinctly influence the aromas of specific varieties.
If you have a chemistry degree, you’ll have no problem combing through the data we compiled and understanding its relevance within the legal cannabis industry. Want us to explain it more simply? That’s what we’re doing today.
Read on for terminology clarification, a breakdown of the experiment and its key findings, plus an explanation of how this research may impact the regulated cannabis industry.
The Science of Exotics: The Experiment
In order to discover the chemical origins of exotic cannabis aromas, we gathered thirty-one different varieties. However, to perform in-depth qualitative and quantitative assessments, we needed samples that would allow our instrumentation to pick up on low-concentration analytes. This requirement made ice hash rosin ideal for its increased levels of aromatic compounds.
Ice Hash Rosin: A cannabis concentrate created by adding fresh frozen flower to ice and water. It is then gently stirred, trichomes are filtered out and freeze-dried before being pressed under gentle heat to produce a thick oil.
2-dimensional gas chromatography (GCxGC): A leading analytical instrument capable of providing the most comprehensive insight into aromatic chemical composition.
Our sensory analysis was completed by a panel of seven cannabis users who were asked to describe the aroma of each variety. They rated the “exotic score” of each sample on a scale of 0-100, they were allowed to use any terminology they found useful, and the results of the panel were then gathered and analyzed.
From there, a chemical analysis helped us understand why our sensory panel ranked varieties the way they did. This involved analyzing each sample using our advanced 2-dimensional gas chromatography (GCxGC) and comparing those results to our sensory panel responses.
The Science of Exotics: Key Takeaways
In all honesty, between the findings from our sensory panel and the insights we gathered from our chemical analysis… we were blown away. At first, we found more questions than answers. So, we ran more tests. And then MORE tests. Suffice to say that the science of cannabis aroma may never be the same again.
Flavorants: Non-terpene compounds (esters, volatile sulfur compounds, alcohols, etc.) found in low concentrations that are responsible for the unique and diverse flavors of cannabis.
Total Aroma Percentage: The portion of a product's weight constituted by volatile compounds responsible for its aroma.
Exotic Cannabis Varieties: Cannabis varieties that are unusually sweet or savory. The former often have aroma descriptors such as sweet or fruity, while the latter include chemical or savory
Redefining “Exotic”
Our sensory panelists helped us realize that our concept of “exotic cannabis aroma” needed to be reevaluated. Instead of just “sweet or fruity” aromas, our panelists described varieties that were “savory” or “chemical.” This has led to the creation of the “Abstrax Exotic Cannabis Aroma Spectrum.”
Figure 1. Schematic illustrating the wide spectrum of cannabis aromas reported from a sensory panel for multiple cultivars. The numbers in parenthesis are each variety’s Exotic Score (explained below) that indicates how exotic the cultivar is. Higher numbers indicate the variety was ranked to be sweet or fruity, while lower numbers indicate the varieties were ranked as not sweet or fruity. The numbers do not correspond to quality - meaning a higher number is not better than a lower number, rather just aromatically different.
NO Correlation Between Dominant Terpenes and Exotic Score Rank
After comparing the chemical analysis with the data from our sensory panel, we couldn’t find trends correlating dominant terpenes present in cannabis varieties to their exotic score.
For example, Grape Pie x Do-Si-Dos was the highest-ranked variety. However, it shared the same dominant terpenes with GMO, which was the lowest-ranked. If you’re familiar with their aromas, you know they’re very different. This indicated that terpenes alone couldn’t be responsible for aroma.
Further analyses comparing the aromatic chemical fingerprints of each cultivar confirmed this.
Non-Terpene Compounds Show Clear Differences Between Varieties
When we compared things like esters, volatile sulfur compounds, alcohols, etc., we found clear differences. This class of compounds we are referring to as “flavorants” was concluded to be responsible for many of the unique and diverse flavors within cannabis.
Additional Analysis Revealed 60+ Unique Flavorant Compounds
Obviously, we were too curious to stop there. Once we found the missing piece of the puzzle we performed additional analyses and identified more than sixty unique flavorant compounds. This led to—you guessed it—additional testing to understand how these new compounds fit into our understanding and perception of cannabis aroma.
Unique Flavorant Compounds
Tropical Volatile Sulfur Compounds: Major contributors to cannabis varieties with strong citrus and/or tropical fruit aromas. The majority of tropical VSCs were found in high-ranking exotic varieties and relatively few were found in low scoring varieties.
Indole (1H-indole): Likely contributes to prototypical cannabis aromas and possesses a floral, mothball-like scent.
Skatole: The aroma of Skatole is complex. It changes drastically at various concentrations and in the presence of other aroma compounds.
While total aroma percentage has often been equated with “terpene concentration,” our findings determined that wasn’t accurate. The Exotic rankings our sensory panelists assigned to the cultivars did not correlate to their total aroma percentage. Some varieties with the highest Exotic Scores actually recorded the lowest total aroma weight percentages.
Flavorants Significantly Influence Aroma Despite Minor Concentrations
Despite constituting approximately 1-4% of total volatile compounds, the distinct positive correlation between this minor percentage and Exotic Score indicates that their influence on aroma is disproportionally significant.
Put more simply? Even when there’s only a tiny amount of flavorants, they have a significant impact on exotic cannabis aroma.
Figure 2. The percentage of volatile fraction weight in the measured samples exhibits minimal correlation to the exotic nature of cannabis. Flavorants display a positive correlation with the Exotic Score, underscoring their significant role in contributing to these distinct aromas. In contrast, monoterpenes/monoterpenoids and sesquiterpenes/sesquiterpenoids show negligible positive and negative correlations, respectively, indicating their relatively inconsequential contribution to the unique aromas of the varieties studied.
Are Terpene Aromatic Contributions to Cannabis Overemphasized?
Similarly to how terms like indica and sativa no longer provide the same value and accuracy when it comes to cannabis classification, our research indicates that terpenes may no longer provide the necessary chemical information to differentiate varieties in regard to aroma.
A 2022 study found that US-grown cannabis tended to fall into one of three classes (terpinolene/ß-myrcene, D-(+)-limonene/ß-caryophyllene, or ß-myrcene/pinene dominant varieties). However, varieties with drastically different aromas often ended up in the same class. If dominant terpenes were solely responsible for cannabis aroma, these instances would be uncommon.
Considering all that our newest research has revealed, we think it’s fair to say that the aromatic contributions of terpenes have been overemphasized. However, there is evidence to suggest that, while they may not be the defining elements of exotic aroma, they do contribute various characteristics.
The Science of Exotics: Why These Results Matter
In addition to simply improving our understanding of cannabis aroma, the implications of this data are especially important for cannabis consumers, manufacturers, marketers, and regulators.
For consumers, this information could lead to more accurate information with which to find their desired products. At the moment, many certificates of analysis (COAs) only contain cannabinoid and terpene information, which can be misleading for consumers who rely on terpene concentration for product selection. With a greater chemical understanding of cannabis aroma, testing accuracy will improve and cannabis labeling can rectify misconceptions.
For manufacturers, a more in-depth understanding of the compounds that contribute to cannabis aroma means greater control over product development. This will ultimately lead to products with more authentic cannabis aroma, that display more accurate information, and product innovation.
In addition, there is even the potential that these newly discovered flavorants possess additional functional applications. For example, indole and skatole have similar chemical structures to compounds with antiproliferative properties in some cancer cells. Researchers can now investigate whether various flavorants possess similar properties.
Abstrax Tech: Promoting Excellence in Cannabis Research and Innovation
At Abstrax Tech, we pioneer the research of cannabis flavor and aroma. That’s not just a fluff statement. We conduct industry-leading, peer-reviewed research on cannabis to push the industry forward with better education and collaboration. We are passionate about the cannabis industry and will continue promoting excellence in research and innovation.
Do you want to learn more about the chemistry of exotic cannabis?
- The Science of Exotic I: The Dawn of Flavorants - Learn why terpenes might not be the most effective method for discerning the aromas of cannabis.
- The Science of Exotic II: The Curious Case of Chem – Learn what makes some of the most savory or chemical-like varieties smell and taste the way they do.
- The Science of Exotic III: The Trio of Tropicanna – Learn why certain cannabis varieties have intense, pungent citrus notes that seem to linger. Spoiler: it’s not Limonene!
- The Science of Exotic IV: Sweet – Coming soon! Learn about all of the new chemistry in many of your favorite sweet, fruity, or dessert-like varieties.
Minor, Nonterpenoid Volatile Compounds Drive the Aroma Differences of Exotic Cannabis
Iain W. H. Oswald, Twinkle R. Paryani, Manuel E. Sosa, Marcos A. Ojeda, Mark R. Altenbernd, Jonathan J. Grandy, Nathan S. Shafer, Kim Ngo, Jack R. Peat III, Bradley G. Melshenker, Ian Skelly, Kevin A. Koby, Michael F. Z. Page, and Thomas J. Martin
Experience Flavorants Indole and Skatole
As the first to benefit from our breakthrough discovery, GMO is kicking off the next era of botanical aromatics. Flavorants Skatole and Indole multiply its notoriously savory and funky notes for a loud, gassy, and undeniably pungent finish.