Hop terroir

From Vol. 6, No. 9, January 2023. This recap of what appeared in Hop Queries during the previous six years, from a few other places I’ve written about the topic, and in “For the Love of Hops.”

Before deciding what to include here, I had a conversation with Single Hill Brewing co-founder Zach Turner, who is in a unique position to evaluate the impact of terroir not only because the brewery is in downtown Yakima, Washington.

Turner’s first job in Yakima was at Hopunion, before the company merged with Yakima Chief to form what is now known as Yakima Chief Hops. He and Ralph Woodall evaluated every lot of hops Hopunion took in from Idaho, Washington and Oregon. The difference between Cascade and Centennial grown in the respective states was easy to perceive.

After the merger, Turner evaluated thousands of lots, was able to mine a growing database and found differences he attributed to geography.

Since Single Hill opened in 2018, he sees only harvest snapshots, but more of them than almost any other brewer gets, particularly when Single Hill is brewing fresh hop beers. Those beers are better than pretty good. Energy Cone IPA, brewed with six varieties from six farms and eight different lots, won best of show at the 2021 Yakima Fresh Hop Ale Festival, then gold at the 2021 Great American Beer Festival. Not every one of their fresh-hopped beers includes quite as many different hops, but most have several.

Single Hill brewers — and, often, those with whom they’re collaborating — visit a farm to pick up unkilned hops available on a brew day, along with freshly kilned cones, which they take back to the brewery to make into pellets on their own mill. They then use those either on the hot side or for dry hopping.

“This means our beers all have the character of the harvest as it’s happening, and their flavors change across harvest as the hop varieties change,” Turner told me for a story in Brewing Industry Guide.

That sounds like terroir to me.

We talked the role of geography, about the impact of country/region/farm/plant maturity on hop character, and eventually about the importance of farm practices. He asked if I would include the last as a contributor to of hop terroir. In 2005, when I named my blog Appellation Beer and began wondering out loud about the role place plays in how we perceive beer, I’m not sure how I would have answered that question.

I do now, and whatever definition you choose matters. So we’ll start there.

The wine view – and mine
Primarily from “For the Love of Hops,” although my conclusion is more recent

“‘Terroir’ is a concept that is rapidly emerging as the unifying theory of fine wine,” Jamie Goode writes in “The Science of Wine.” “The traditional, Old World definition of terroir is quite a tricky one to tie down, but it can probably be best summed up as the way that the environment of the vineyard shapes the quality of the wine. It’s a local flavor, the possession by a wine of a sense of place or ‘somewhereness.’ That is, a wine from a particular patch of ground expresses characteristics related to the physical environments in which the grapes were grown.”

Amy Trubek offers something more inclusive in “Taste of Place: A Cultural Journey into Terroir,” arguing that in France the narrow scientific and broad cultural definitions of terroir are often used simultaneously. “This broader definition of terroir considers place as much as earth. According to this definition, the people involved in making wine, the winemaking tradition of a region, and the local philosophy of flavor are all part of terroir,” she writes. “Unlike the narrow view of terroir, this humanist point of view is not really quantifiable. Terroir speaks of nature and nature’s influence on flavor and quality, but here the human attributes we bring to ‘nature’ are cultural and sensual rather than objective and scientific.”

That is a step closer to the suggestion Dogfish Head Craft Brewery co-founder Sam Calagione made during his 2006 Craft Brewers Conference keynote speech: “Je parl francais en peu and I’m pretty sure the translated definition of terroir is dirt. The wine world has wrapped this one word with mighty voodoo powers and created a cult of exclusivity around it. Breweries have terroir as well. But instead of revolving around a patch of land, ours are centered on a group of people.”

This leads to my personal definition, which you not obligated to share. What I choose to call hop terroir results from the interaction of growers, plants and multiple environmental factors.

A scientific explanation
From “For the Love of Hops”

All plant species have methylated DNA, which causes some genes to be “switched on” more easily than others. Differences in soil, day length, temperatures, amount of rainfall, and terrain all may influence the methylation process. The underlying DNA does not change, but the methylation pattern can be different. That change in pattern may result in different aroma compounds within a hop.

Researchers at the University of Hohenheim in Stuttgart used AFLP fingerprinting to analyze the similarity of Tettnanger hop plants to other varieties in 2002, reaffirming other surveys that concluded that Tettnanger, Spalt Spalter, and Saaz hops are so closely related they may be grouped together as “Saazer hops.” The Tettnang region (47.7° latitude) receives both more rain and more sunshine than areas around Spalt (49.2°) or Žatek (50.3°). Žatek is about 700 feet above sea level, Spalt 1,200 feet, and Tettnang itself is 1,500 feet (although fields range from 1,300 to 2,300). Not only are many of the trellises in Tettnang taller, but many plants are 80 to 100 years old, compared to 25-year-old plants in other regions.

Their alpha/beta and oil profiles are similar but not identical. The Hop Aroma Compendium’s descriptions of aromas found in each of them reflect those differences:

Saaz: “Spicy, woody, such as tarragon, lavender, cedarwood, and smoked bacon.”

Spalter: “Woody aromas … reminiscent of tonka beans and barrique, with slightly sweet notes of ripe bananas.”

Tettnanger: “Woody aromas and cream-caramel components, such as gingerbread and almonds, predominate, combined with fruity blueberry notes.”

From Oregon

Subscribers who have been around since 2019 will remember the first report here (Vol. 3, No. 4) of research at Oregon State University, which began in partnership with Coleman Agriculture and Red Hill Soils. That research continues, expanding each year, and drawing more attention; that is, being talked about outside of scientific and niche (such as here) publications. A few highlights:

– This began after a conversation between Tom Shellhammer at OSU and Liz and John Coleman, who grow 2,500 acres of hops on four different locations in Oregon. “(Liz) was, they live in wine country and hop country and they go to wineries and there’s this stuff about terroir, do you think there is anything there,” Shellhammer said.

– The initial study included two hop varieties, Sterling and Centennial, grown across four different locations in the Willamette Valley, and two main types of soil. The results of both chemical and sensory analysis revealed various differences. For instance, a farm in Independence with sandier alluvium soil and greater diurnal day-night temperature fluctuations produced Centennial with higher levels of geraniol and linalool. Just as important: Members of a panel of professional brewers and hop growers were able to discern regional differences via triangle tests within the Centennial samples.

– “This isn’t the end of the story, it just verifies that there is something there worth investigating,” Shellhammer said at the time. “The next part of the journey is to dig deeper, both metaphorically and literally, to find out what drives these differences and how we can manipulate them to achieve specific results.”

– Sure enough, the journey goes on. Research expanded to add more farms, with some in Washington, and more varieties, such as Cascade, Mosaic, Simcoe and Strata. The most recent report is here. When the results of more research become available I will include them in Hop Queries, but without repeating all of the words in this issue.

From Germany

In trials conducted at the research brewery in St. Johann researchers compared Cascade and Comet hops grown in the Yakima Valley and Halltertau regions. They found differences in composition that could be measured, and while they were reflected to a lesser degree by sensory panelists that did not lead to clear preferences. Noteworthy:

– Both the German-grown Cascade and Comet had higher levels of total and low-molecular polyphenols including xanthohumol, which is likely why the quality of bitterness in beers brewed with the Hallertau hops was assessed a slightly better.

– The hops grown in the Yakima Valley had higher levels of linalool.

– The Hallertau Cascade had higher quantities of the fruity esters isobutyl isobutyrate and 2-methylbutyl 2-methylpropanoate than either American variety.

– The Cascade beers showed fewer differences between the growing regions than the Comet beers.

From Belgium
Reported in Hop Queries Nov. 5, No. 6, October 2021

A team at Ghent University working with De Proefbrouwerij produced eight single-hop New England-style IPAs using three hop varieties grown in five regions. They found:

– The perception of beers hopped with Amarillo grown in Germany and Washington was distinctly different, while those from Germany and Idaho were more similar. Washington Amarillo produced beers perceived as citrussy and fruity. German Amarillo were more woody and resinous, while spicy/peppery notes were detected in the Idaho Amarillo.

– Using Cascade grown in Washington and Germany resulted in beers with similar aromas that were different than those from beers hopped, and dry-hopped, with Australian Cascade. Descriptors for the German beers included grapefruit, tangerine, lychee apple and pineapple. Washington descriptors were grapefruit and various tropical aromas. The Australian Cascade aroma was more complex, but not as intense, and the bitter intensity was higher.

– Beers brewed with Centennial hops from Belgium and Washington were notably different. The Belgian version had more esters and was fruity (pineapple, tropical) and citrussy (orange). The Washington version was citrussy (grapefruit, lime) but also woody (resinous) with more intense bitterness.

Down on the farm
From a story I wrote for The New Brewer in 2021

In a paper in the Journal of Agricultural and Food Chemistry the authors concluded, “It is essential for future studies assessing the impact of different farming practices and locations (i.e., regionality, terroir, etc.) on the constituents in hops important for hoppy beer flavor to consider and account for the impact of hop maturity as well as genetics.”

In this study, researchers evaluated Cascade, Citra, Mosaic, Sabro and Simcoe hops from two farms per variety harvested at three distinct maturity points. Not surprisingly, hop variety accounted for the biggest variation in compounds known to impact aroma and flavor. Maturity was the next most significant factor.

“By reporting that hops are different in aromatic quality and not controlling for maturity (in studies investigating regionality), one could simply be reporting that hops from different regions are just more or less mature based on the preferences of growers in different regions to harvest at different maturities and/or due to the fact that field-specific characteristics might lead to hops being more or less mature (more sunlight, precipitation amount, humidity differences, etc.),” Scott LaFontaine, the corresponding author, explained to me at the time.

“This is unlike alpha, which in most varieties reaches a peak/ plateau at some point and then remains relatively stable. This is why the connection between brewers and growers is critical because if we discuss hop quality in terms of aromatic potential we need to understand that maturity matters.”

(Should that name look familiar, I’ve quoted LaFontaine many times, including in Hop Queries, originally as a graduate student at Oregon State University. When the paper cited here was published he was a Humboldt Fellow hosted by Versuchs- und Lehranstalt für Brauerei (VLB). Now he is an assistant professor in Food Chemistry at the University of Arkansas.)

Final thoughts, Part 1
Also from Hop Queries Vol. 5. No. 6, October 2021

A post at The Drop (a wine website) suggests terroir may give winemakers a get-out-of-jail-free card and asks a series of questions. “Did your grapes fail to ripen properly? That’s just your terroir speaking. Did you just plant a vineyard three years ago and the results are underwhelming, but you’ve got bills to pay? Slap on a single-vineyard designation and charge big bucks because you’re exploring the terroir of your little corner of nowhere. Did raging forest fires leave your wine tasting like an ashtray? Terroir!”

More important, in my view, is this: “There are cynical reasons for this emphasis on the piece of land over the people. Land can be owned, and people can’t. If a winery owner wants to enhance the reputation and value of their wine, it is far better to extol the virtues of wherever the wine comes from, instead of the work of the people who make the wine, since they might eventually join a competitor or strike out on their own. If the belief is that the patch of land makes the grapes great and not the people who work it, not only can those grapes command a higher price, but skilled workers can easily be underpaid or even replaced with machines.”

Final thoughts, Part 2
From MBAA Technical Quarterly Vol. 56, No. 4

“First Step Toward Understanding Regionality of Hops” was published in 2019 after the first round of the collaborative study in Oregon referenced above, and in my opinion established parameters everybody should think about when they are discussing hop terroir. This is the TL;DR version. I recommend reading the entire paper, available to MBAA members (so join, if you haven’t).

Accentuating the positive:
– In today’s craft brewing world, regional distinction could create a new foundation by offering the brewer vast information to support his/her innovations.
– For brewers, regional diversity data can serve as selection verification and result in better-informed decision making as they work with hop merchants to identify hops best suited for their brewing goals.
– Terroir, culture, and regionality play a role in consumer choice and become a part of the story that defines and differentiates a brand.
– A longer-term, comprehensive study will lead to better informed decision making for growing practices, planting locations, irrigation, and fertilization.

But, temper your enthusiasm:
– It will take considerable time to understand, characterize, and map regional diversity. Some differences that ultimately define a plot of ground may be positive and some may be negative. In most cases, they likely will all vary in brewer preference.
– Although regional differences may be identified and characterized with science and data, there could be a point at which brewers and consumers will decide based on preference. Regional differences could then be misinterpreted as “better” or “worse.”
– There could be a risk of differentiating too much, and states could lose a sense of comradery, particularly if some farmers find their hops are grown in an area that is perceived as less than desirable.
– There are possible negative repercussions on land value with regard to acreage deemed less desirable for hops, or conversely, the triggering of inflated real estate prices for prime hop growing regions.
– There may be unknown and unintended consequences on the hop supply chain structure and hop selection processes.