Does your favourite beer contain humulene? Or myrcene? How about alpha-pinene? There’s a good chance it does — but maybe you have no idea what those things are.
Well, we’re here to tell you. They’re terpenes, a set of natural compounds produced by the hop plant. They help make beer smell and taste fresh, flavourful and vibrant.
Nowadays, these compounds are being recognized as the stars that make beer delicious. Ready to learn more? It’s terpene time!
What are terpenes?
Chemically speaking, terpenes are the largest component of essential oils. People have used essential oils in traditional medicines and fragrances for millennia. The terpenes in them make things smell nice and distinctive.
Where do terpenes come from?
Essential oils and terpenes come from plants. For example, lemon and dill have loads of terpene-heavy essential oils.
But we’re all about beer. So let’s talk about the terpenes you’ll find in another plant that’s chock full of essential oils. You guessed it: hops.
The female flowers of the hop plant develop into tough little cones. These contain sticky, bitter blobs of golden resin that come from a part known as the lupulin glands. This is the good stuff. The essential oils in that goo are full of the terpenes that give beer its recognizable bitterness and aromas.
What do terpenes do in plants?
The terpenes in plants act as natural pesticides, and they have some antifungal properties, too. This helps explain why brewers adopted hops in the Middle Ages: to help preserve their suds.
The fact that terpenes smell great? Well, that’s just a tasty bonus.
What do terpenes do in beer?
Terpenes’ main job is to add aromatic complexity. So how do they do that? Easy. Their chemical structure reminds our noses of all sorts of nice, interesting things. They can make you smell wood, earth, spices (often clove and pepper), flowers (a whole bouquet of ’em) and/or fruits (from apple to mango to lemon).
It’s worth noting that there’s no one chemical or compound that gives hops their “hoppiness.” A potpourri of elements create their bitter flavour and complex scents; terpenes are just a part of that equation. For example, alpha acids are another natural chemical in hops, and they give the beer a jolt of bitterness.
How do brewers add terpenes to beer?
If you want to unleash the deliciousness of terpenes in beer, you traditionally do it by adding hops. Brewers add them to the kettle at a couple of points during the brewing process, boiling them in the beer like tea.
For some brewers, that’s it. Others add extra “dry” hops later on in the brewing process. Dry hopping is a great move if you’re trying to increase your terpene content.
Which terpenes are common in beer?
Time for a cheat sheet! Here’s a quick rundown of some common terpenes found in beer and the main flavours and aromas they add.
- Alpha-pinene: Pine, rosemary, wood
- Alpha-terpineol: Lilac, flowers, pine
- (Beta-)caryophyllene: Black pepper, wood, spice
- Farnesene: Green apple, wood, herbs
- Geraniol: Rose, geranium, fruit
- Humulene: Earth, wood, spice
- Limonene: Bold citrus (lemon and orange), juniper
- Linalool: Lavender, flowers, orange
- Myrcene: Green herbs, mint, clove
Which terpenes are found in which hops and beer styles?
Brewers don’t list the terpenes in their beers, but they sometimes tell you which hops they used. You can also make an educated guess based on style with our hints below. Use this list of hops and beer styles to figure out which terpenes you’re catching a whiff of.
- Cascade, Citra, Centennial, Mosaic and Ultra hops. These are common in American pale ales (APAs) and India pale ales (IPAs). They give fans of modern-style American ales that spicy citrus aroma they can’t get enough of. They all contain lots of myrcene and often geraniol, too.
- East Kent Golding, Fuggle, Hallertau and Tettnanger hops. These European varieties are found in a lot of old-school beer styles from Europe and the British Isles. They contain lots of humulene and (beta-)carophyllene. Sniff for woody, earthy and mildly spicy aromas.
- Saaz and Sterling hops. German- and Czech-style beers, including pilsners, often use these related varieties. They showcase the aroma of farnesene. It’s delicate, zesty and hard to describe; it’s also found in green-apple skin and gardenias.
- Liberty, Crystal, Nugget, Ultra and Mount Hood hops. Often found in North American–style pale lagers and ales, these are close cousins. Mildew-resistant descendants of the German hop variety Hallertau, they contain a whole lot of linalool, which adds a fresh floral aroma.
Which foods match well with different terpenes?
If you’re keen to dig into terpenes, why not plan a whole meal around them for a full-on taste and scent experience? Here are a few pointers to get you started.
- Munching on myrcene: APAs and IPAs. The spicy, zesty citrus notes in these beer styles are fun to pair with dishes that have a bit of kick and go with a squeeze of lemon or lime. Make our Grilled Mexican-Style Street Corn with IPA part of the menu.
- Hungry for humulene: Pilsners, bocks and British-style pale ales. Humulene is found in basil, ginger, cloves and black pepper. So it makes sense that many traditional European beers taste great with Southeast Asian dishes, like our Thai Chicken Curry with Squash & Ale.
- Feasting on farnesene: German- and Czech-style beers. This terpene has so much aroma to give that people describe it in all sorts of ways. They say it tastes and smells like apple peel, ginger, flowers and more. These aromas can help lighten up heavy meals that are rich and/or meaty. If you catch a whiff of sweet floral spice in your lager, see if it balances our rich Lager, Gruyère & Emmental Fondue or Pilsner Chimichurri Burgers.
- Lapping up linalool: Light-bodied North American beers. With its notes of lavender, herbs and fresh citrus, linalool is calming and soothing. If you sense those aromas in your beer, enjoy it with a sunny, herby dish like Melon, Feta & Mint Salad with Honey Lager Dressing or Italian Pasta Salad with Lemon Lager Dressing.
What’s next for the terpene trend?
Why is everyone talking about terpenes? Part of the reason is that brewers have more access to terpene extracts and blends. They can now experiment with adding terpenes directly to a beer, enhancing what the hops already give them.
And whenever brewers get a new tool to play around with, they experiment. So keep your eyes open for new beer developments.
At the same time, there’s still a lot to learn about terpenes. Beer is a complex chemical brew, full of interactions that create new aromas and flavours. We have a good idea of what kinds of aromas each terpene brings by itself, but there’s a lot we don’t know about how terpenes react with each other (and with other components in suds) to create new and wonderful aromas. It’s not as simple as “Hop X gives you Terpene Y, resulting in Flavour Z.”
In other words, beer is more than the sum of its parts. And it’s still a delicious mystery in lots of ways. That’s a big part of why brewers are always trying new things — and what makes beer so much fun to explore.