Why Some Beers Taste Like Cannabis
There is nothing like opening a cold, refreshing beer on a warm summer afternoon. The second you pop the cap off the bottle, the enticing aroma of heavenly hops embraces you, but occasionally, you might catch a whiff of something a touch more potent. You might look around to see if any strange smoke is wafting around with a puzzled look on your face, recognizing the very distinct scent of cannabis.
While the smell might be coming from someone having a good time near your general area, the culprit for the odor is probably right in your hand. Beer can sometimes acquire a noticeably musty bouquet, and there are a couple of specific explanations as to why. One reason stems from a chemical reaction that can occur if beer gets too much sun. When beer is brewed, chemical compounds called iso-alpha acids are produced that contribute to the beverage's noticeable hoppy flavor. If exposed to excessive sunlight, those chemicals turn into free radicals and combine with proteins to form a molecule dubbed 3-methyl-2-butene-1-thiol. This compound has an incredibly robust scent and exudes an aroma similar to that of a cannabis plant.
Another reason some beers can smell like a hippie jam-fest is because hops and cannabis share a genetic heritage. Because of this relationship, they share certain chemical compounds in their makeup, some of which are called terpenes. These chemicals are responsible for the odors emitted from many different plants and are prominent in both hops and cannabis.
Terpenes are one main factor in skunky beer
Terpenes are organic compounds responsible for how many plants smell, and hops and cannabis are loaded with them. Some notable examples of terpenes are limonene, prominent in lemons, and pinene, which gives pine trees their signature aroma. Humulus lupulus and Cannabis sativa — the scientific names for hops and cannabis — are both genera of the family Cannabinaceae and having stemmed from the same ancestor, they still share some similarities in their chemical structure. One of the more prominent terpenes in hops is myrcene, which emits a pungent, earthy odor. Cannabis also contains a copious amount of myrcene, with some strains comprising 65% of myrcene in their overall terpene profile.
Though terpenes are responsible for the inherent skunky scent stemming from genetics, this affects some beers more than others. Breweries brew beers using different methods and various types of hops, so some hop varieties will have a more pronounced odor coming from their terpenes. But all beer is susceptible to the chemical reactions occurring from sun exposure. Clear glass bottles are the easiest for UV rays to penetrate and corrupt your beer, and they are likely the first to become a little skunky if left in the sun. Brewers eventually discovered that colored bottles could prevent beer from going bad so quickly, which is why many beer bottles you see today are either brown or green.
Brown bottles prevent beer from getting skunky -- if desired
Around the 17th century, keeping beer fresher longer by bottling it started gaining popularity, but unwelcome pungent flavors were still a problem. Once it was discovered this was due to sunlight exposure, beer producers began using brown bottles to house their beverage, effectively blocking out many of the sun's UV rays. But during WWII, brown-tinted bottles became unsustainable. Brown bottles require sulfur during construction, but sulfur was a valuable war resource. Green bottles are made instead of iron(II) oxide — typically used as an industrial coloring chemical. Some manufacturers started marketing the green bottles as premium beer, which is part of why they still exist today. Brown bottles are still considered the best way to avoid beer becoming "lightstruck." So your Pilsner Urquells and Heinekens in green bottles may have a skunkier flavor than a brown-bottled Sam Adams if left in the sun too long.
However, some individuals want their brew to smell and taste like they're going to Funkytown, and major beer producers have supplied that demand. Sierra Nevada Dankful IPA boasts an easily drinkable flavor profile with mild cannabis notes. Other beers take a bolder approach, like Sweetwater 420 Strain G13 IPA. Some describe the cannabis odor of this beverage as so intense you can smell it from a few feet away. Whether you enjoy a little "Maui Waui" flavor in your beer or not, whatever you do, have a good time, and please do so responsibly.