Ross Koenigs’s journey into cannabis happened somewhat by chance. Hemp researchers connected to Colorado State University visited the New Belgium taproom on an unremarkable afternoon in April 2015 and asked to speak to Koenigs’s boss, Peter Bouckaert. The U.S. Congress had just legalized hemp cultivation for research purposes under the 2014 Agricultural Act, and many in Colorado jumped at the opportunity to study this newly legalized plant.
The researchers wanted to show Peter some of their plants, saying that they had many distinct aromas that might be of interest to brewers. Bouckaert, famous for his curiosity and penchant for novel brewing ingredients, got excited. He grabbed a few staff members, piled them into his car, and drove to the south end of Fort Collins to visit the greenhouses of a company now known as New West Genetics.
When Koenigs first smelled the different plants, he didn’t really get it. He didn’t really understand much about hemp at the time, but he did know one critical thing: It’s related to marijuana but doesn’t get you high. The plants looked similar to marijuana and most of them had nice aromas, though some smelled quite awful. It wasn’t until Koenigs dug a bit deeper that the light really clicked on for him. Koenigs had too many preconceived thoughts about cannabis. He figured it would be a cold day in hell before the government allowed brewers to put THC in beer, so exploring options in hemp would be a wasted effort—there was nothing interesting in cannabis if it didn’t have THC.
Koenigs fell prey to what a lot of people think about cannabis: It’s a plant that can get you high and nothing more. He’s pretty sure he remembers saying something to the effect of, “Why would he put fake weed in my beer?” It seemed boring at the time and, to be fair, he thinks he may have been suffering from the bad information generally available. This poor-quality information comes from both proponents and opponents of cannabis; it reflects what happens when something is demonized and criminalized something for so long. The end result is typically colloquialisms that have little semblance to the truth.
From a legal perspective, the only difference between the two plants is the content of delta-9 tetrahydrocannabinol, more commonly known as THC. If a cannabis plant is at or below 0.3% THC by weight, it is hemp. If it’s above 0.3% THC by weight, it is marijuana. Both are cannabis. Both plants are varieties of Cannabis sativa L. under the Linnaean classification system; therefore, despite common misconceptions, both hemp and marijuana are regarded by botanists as the same species. Over the course of a couple of generations in the wild, marijuana plants can become hemp and hemp plants can become marijuana.
What Koenigs came to discover was that hemp has a lot of interesting qualities and should be of great interest to brewers. When describing what hops are to their brewery tour guests, most brewers cite as a piece of trivia that hops and cannabis are botanical cousins. The vast amount of research that has gone into understanding hops in the last 100 years gives us the perfect lens through which to study cannabis.
Brewers are uniquely suited to understanding and promoting this newly legalized plant. Many of the processing technologies used for hop products are applicable to hemp; brewers have expertise in analyzing related biochemical constituents commonly found in hops and hemp; brewers have a shared expertise turning agricultural products into useful consumer products, and they understand and respect the power of intoxicants and can communicate the responsibility required to consume them in a safe and legal manner.
Since that chance encounter where Ross was introduced to the world of hemp, he’s developed quite a bit of knowledge and expertise around how to brew with it. Since he focused most of his time at New Belgium researching and developing hoppy beers, his role put him in a unique position to translate that knowledge and skill base into a useful resource.
Cannabis is a tricky subject. Some aspects of cannabis will feel very familiar to brewers, while others will feel foreign. It took Ross and a group of brewers about three years from that first moment in the greenhouse to introduce America’s first nationally available hemp-flavored beer, The Hemperor.
During that time, they were forced to navigate various legal pitfalls and a regulatory environment that didn’t know what to do with such a product. At the end of it all, they were barely scratching the surface of the possibilities that marrying cannabis and beer held, so Koenigs and the team proceeded to do further research and learn more from people in the cannabis industry, to fully understand the possibilities of hemp. Brewing with Hemp is a continuation of that work and, it is hoped, will make the subject a bit more accessible.
The title of the book, Brewing with Hemp: The Essential Guide, indicates that most of the book covers hemp and only periodically talks about marijuana. The first reason for that should be obvious: This is a book for a brewing and beverage industry audience; some hemp ingredients can be added to beer, but marijuana ingredients cannot be legally added. The government may permit marijuana in [alcohol-containing] beer one day, but considering it is prohibited to add caffeine to alcohol it seems unlikely the government will allow brewers to add a powerful psycho-active to their products.
Cannabis Aroma Compounds
Generally, there is a complex mixture of cannabinoids and terpenes in any given cannabis plant. All cannabis plants are Cannabis sativa, this is true, but there are multiple varieties, cultivars, and “strains” within the species that have arisen over centuries and millennia thanks to humans breeding cannabis for specific uses.
Given the confusing taxonomic nomenclature that exists around hemp and marijuana types, especially the naming of strains in the marijuana market, academic researchers have increasingly turned to analyzing the biochemical profile of cannabis plants to better identify them unambiguously. These “chemical varieties” are usually referred to as chemotypes or chemovars.
The primary terpenes of C. sativa derive from a combination of inherited genetic traits and environmental factors. Provided growing conditions are consistent, terpene synthase enzymes will produce terpenes characteristic of a particular cannabis chemovar, and then environmental factors do the rest to produce further derivative compounds.
Brewing with Hemp will focus on some of the primary terpenes created by C. sativa to help give better language to the distinctive, yet often hard to describe, cannabis aroma. When developing The Hemperor at New Belgium, this was a very helpful exercise to know how to target specific aromas to make sure we were getting a “true-to-type” cannabis aroma. They honed in on a key term to help them standardize it: dank.
When someone is asked to define the term dank, they often respond that it’s something that smells like cannabis flower; in turn, cannabis is described as smelling dank. This catch-22 situation can be maddening when trying to accurately describe the differences between strains of cannabis, or even just to provide more extensive descriptive language. Koenigs does his best to describe the primary “aroma buckets” that best make up his definition of the term dank: woody, herbal, floral, stinky, and fruity. In Koenigs’s opinion, every strain of cannabis has these five aroma buckets in varying amounts.
The woody aroma bucket is composed of some of the most dominant olfactory monoterpenes in cannabis: myrcene and pinene. Typically, myrcene and pinene make up the majority of essential oil from cannabis, so it makes sense most cannabis smells somewhat woody to people who have been trained in this lexicon. To Koenigs, woody aromas can range from pine sap to stripped tree bark to pencil shavings. Of course, the interplay with the herbal and floral components also generates descriptions like peppery spice, dried leaves, hay, cedar, eucalyptus, and soil.
The herbal bucket is composed of many of the dominant olfactory sesquiterpenes in cannabis, such as ᵝ-caryophyllene and humulene. This group of compounds are the second-most abundant constituents of cannabis essential oil (behind myrcene and pinene). Sesquiterpenes in the herbal bucket produce a diverse array of dried and fresh herb characteristics, which include notes of ginger, sage, basil, rosemary, oregano, hops, and fresh-cut grass. The interplay of the herbal bucket with the woody, floral, and fruity buckets helps drive the aforementioned woody aromas, plus it contributes to heavily spice-driven aromas like clove, cardamom, patchouli, and caraway seed.
The floral bucket is composed of a smattering of terpenes and terpenoids, including linalool, geraniol, and α-terpinol. While these compounds make up a small percentage of the essential oil of cannabis, they are highly aroma active and contribute significantly to the perceived aroma profile. The floral bucket contributes notes of lavender, lilac, rose, bergamot, and a general perfume-like aroma. Floral aromas interact with fruity and herbal aromas, adding additional notes of peach, apricot, vanilla, citrus fruit, and grape/wine.
There are many types of compounds that comprise the stinky bucket, but the most important are the volatile sulfur compounds. Sulfur-based volatiles run the gamut of aroma compounds (sulfides, thiols, thioesters, thioketones, and others) and are important to cannabis aroma. These compounds make up tiny fractions of a percent of the overall essential oil of the plant yet are so odor active that people can easily detect them at parts-per-trillion levels. The most common stinky odor is skunky aroma, which is mostly made up of the thiols 2-butene-1-thiol and 3-methyl-1-butanethiol.
Some people describe the dank cannabis aroma almost exclusively as “skunky.” Other stinky cannabis odorant descriptors include onion and garlic, cheesy (isovaleric acid), and diesel fuel or exhaust. While these aromas may sound unpleasant, in the right concentrations they accentuate floral and fruity aromas, often creating tropical fruit aromas such as passion fruit, pineapple, guava, grapefruit, and gooseberry.
Finally, the fruity bucket captures many of the oddball terpenes and terpenoids. These exist at varying concentrations in the essential oil of different Cannabis chemovars and are arguably what defines a particular strain or chemovar’s signature scent. Compounds in the fruity bucket can include monoterpenes like limonene, which smells like orange and lime peel, and ᵝ-ocimene, which smells like under-ripe mango and plant-derived aldehydes, esters, and ketones that smell like vanilla, berries, bananas, and coconuts. There are many strains that explicitly call out specific fruits in their names, such as Strawberry Diesel and Pineapple Express. The fruity bucket is typically the dominant driver of these aromas.
Koenigs posits that every Cannabis chemovar can produce at least one characteristic from each aroma bucket, though some tend to over-express the characteristics of one or two. It is best to understand that it is extremely difficult to fully deconstruct the aroma of any whole plant, let alone one as complex as cannabis. Plenty try, and yet, when you smell an attempt to replicate the aroma in isolation, it is frequently missing that je ne sais quoi—dare we say, its dankness? We can understand the main components that make up the cannabis aroma, but what truly defines it are the small quantities of barely measurable, or even identifiable, components. The synergistic relationship between all these components is what defines cannabis’s “dank.”
Table 1: Common Cannabis Terpenes and Derivatives
|Name||Terpenoid Classification||Aroma Descriptors||Plants Common In||Water Solubility|
|β-Myrcene||Monoterpene||Woody, celery, anise, pine resin||Black pepper, mango, hops, thyme, basil||Very low|
|Limonene||Monoterpene||Orange, lime, pine trees||Spruce and fir trees, oranges||Low|
|α-Pinene, β-Pinene||Monoterpene||Woody, turpentine, pine trees, spicy||Pine, sage, eucalyptus, frankincense||Very low|
|Camphene||Monoterpene||Pine needles, earthy, minty, woody||Douglas fir, holy basil, nutmeg, rosemary||Very low|
|β-Ocimene||Monoterpene||Floral, underripe citrus, mango skin||Mint, tarragon, kumquats, mango, bergamot||Very low|
|Terpinene||Monoterpene||Woody, lemon, mint, medicinal||Cumin, cardamom, marjoram, cilantro||Low|
|Geraniol||Monoterpene alcohol||Roses, citrus, floral||Roses, coriander, grapefruit, blueberries||Medium-low|
|Linalool||Monoterpene alcohol||Citrus, blueberry, lavender||Lavender, rose, basil, lemon, neroli, cilantro||Medium-high|
|α-Terpinol||Monoterpene alcohol||Lilac, slight lemon and lime||Cardamom, lemon, grapes, dill, celery||Medium-high|
|β-Caryophyllene||Sesquiterpene||Spicy, woody, pepper, clove||Hops, caraway, oregano, basil, cinnamon||Very low|
|β-Farsenene||Sesquiterpene||Woody, citrus, herbaceous||Apple, orange, pummelo, noble hops||Extremely low|
|Humulene||Sesquiterpene||Clove, woody, peppercorn||Hops, ginseng, black pepper||Extremely low|
|Bisabolol||Sesquiterpene alcohol||Chamomile, citrus, generic spice||Chamomile||Low|
|Eucalyptol||Sesquiterpene alcohol||Eucalyptus, camphor, basil, mint||Eucalyptus, bay leaf, sage||High|
|β-Eudesmol||Sesquiterpene alcohol||Clove, turpentine||Atractylodes||Low|
|Guaiol||Sesquiterpene alcohol||Tea tree, rosewood, cypress||Nutmeg, tea tree, cumin, lilac, pine||Low|
|Nerolidol||Sesquiterpene alcohol||Fresh tree bark, citrus, a pple, rose||Ginger, jasmine, lavender||Medium-low|
|Caryophyllene oxide||Sesquiterpene oxide||Cedar, carrot, earthy||Hops, basil, pepper, rosemary||Low|
Table 1 explores a few abundant terpenes and terpenoids that are frequently encountered in cannabis. The solubility in water is important to review. As a quick rule of thumb, the lower the water solubility of any given terpene, the later in the brewing process you should add your cannabis material to better extract it with ethanol.
About the author of Brewing with Hemp: Ross Koenigs is the owner of Second Dawn Brewing Company in Aurora, Colorado. Previously, he was the brewing innovations manager for New Belgium Brewing Company in Fort Collins, Colo. where he spearheaded the research and development of using hemp in beer when New Belgium introduced The Hemperor HPA.
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