Terroir and Hop Selection
We all know that Nelson Sauvin got its name from its distinctive white wine character, while El Dorado bristles with ultra-sweet fruit flavors. Those are their general qualities, in any case. Yet brewers are getting incredibly sophisticated about hops. Over the past few years, every time I talk to brewers about hop varieties, they pretty quickly turn to hop selection. That’s because the variability in any given hop variety can be striking. Earlier this year, I quoted Von Ebert’s Sam Pecoraro discussing this:
“For Volatile Substance, for instance, we know that we want berry, pine, dank, certain types of berries, and that [guides us] to the type of Mosaic that we’re looking for. When we sit down at the table, it’s not necessarily which is the most intense or the ‘best’ on the table; we look for the one that works for that beer…. Even for one supplier, like Roy Farms, we’ll select multiple El Dorado. We feel like one works better hot side, one works better as a dry hop.”
Researchers at Oregon State University have begun to document this, and last week they released a paper with findings about how Mosaic and Cascade hops differ not just whether they’re grown in Oregon or Washington, but even depending on the farm or location on a farm.
The paper isn’t firewalled, and it contains a lot of detail. Hops are incredibly complicated to study for a variety of reasons: they contain an incredible number of compounds; harvesting time and processing affects those compounds, and the compounds change during the brewing process. Researchers had to control for a number of things and then did chemical analyses on the hops both before and after brewing. And then, of course, the question isn’t really what compounds a hop contains, but what it smells and tastes like, so researchers have to be adept at tasting and empirically categorizing what their noses and tongues tell them.
I’ve spoken with Tom Shellhammer, one of the paper’s co-authors, in the past, and I’m always shocked by all the variables he has to herd. In research he was doing on dry-hopping, the prevailing theory was that oil content was related to good expression in the beer. It turns out even answering that question was a challenge.
If you click through, you’ll see a bunch of information on the compounds in beer, which is quite interesting. In this graph, for example, you can see the ranges of particular compounds in Oregon and Washington Cascades and Mosaic (“Cas-0” is Oregon Cascade, “Mos-W” is Washington Mosaic, etc.). In the upper left quadrant, you’ll see that Oregon’s hops have substantially higher alpha acids, which surprised me, as they’re usually described as being more subdued. Equally interesting is that the alpha acid variation in Oregon Cascades was far greater than in Washington. By contrast, beta acid content was basically the same for both states. Meanwhile, Washington hops have more oils. (HSI is hop storage index—not quite as interesting to the drinker.)
The research looked at hops from 39 regions in the Willamette Valley and Yakima taken from the 2020 harvest. The upshot:
“Our results revealed a high amount of variation in aroma and chemical composition between and among Cascade and Mosaic® hops grown in Oregon and Washington. This regional identity effect was observed on a regional (between state) and a local (within state) level. By combining chemical hop analysis and sensory evaluation of the hop aroma, significant differences were identified that clearly separated the hop samples from the two growing regions. Furthermore, significant differences were observed between hops from different local fields within each of the two regions.”
A press release that accompanied the paper summarized the results this way: Oregon Cascades were described as strong citrus, floral, fruity, herbal and resinous aroma, while “Washington displayed more tropical and sweaty aroma.” Oregon Mosaics sound a lot better, honestly, described as “strong citrus, floral, fruity and tropical aroma.” The Washington Mosaics “displayed stronger sweaty, vegetal and woody aroma.” All right, then!
Tom’s co-authors on the paper were OSU’s Michael Féchir, Yakima Chief’s Curtis Roy, and Garrett Weaver of Coleman Agriculture.