The Where of Grains: On Rob Arnold's "The Terroir of Whiskey"
Rob Arnold | The Terroir of Whiskey: A Distiller's Journey Into the Flavor of Place | Columbia University Press | 2020 | 368 Pages
The idea that the taste of something can tell you something about where it’s grown is packed into the messy French word terroir, probably a shortcut to goût de terroir, and, thanks to earthy associations such as manure, not until the 20th century a solidly positive attribute. By now its meaning is closer to a taste of place and though it can name food and drink alike it is primarily a province of wine, a drink that in its simplest form is fermentation of just-picked grapes. For centuries, winegrowers have fine-tuned their raw materials to this principle, choosing what grapevines to plant where based on how such decisions will affect the taste of what they make. Why then, wonders distiller (“third generation of the whiskey industry”) and plant-breeding researcher Rob Arnold in his second book, The Terroir of Whiskey, have distillers not thought this way about the grains they use?
Whiskey’s long production process (store, ferment, distill grains, age in oak barrels for specific flavors and colors) can seem a long way from wine’s more direct relationship with grapes. But by focusing on the act of cultivation via the grains that are whiskey’s only agricultural aspect, Arnold sets off on a “scientific pursuit of terroir” rooted in analyses of flavor compounds in the species of corn, wheat, rye whose seeds—or grains—whiskey-makers use. His book is simultaneously an attempt to define terroir (a “French-reminiscent internationalism, timeless and de-placed… there is no such place as a terroir,” I wrote in 2020 in my own wish for place-appropriate terminology in Italian wine, for Gastronomica) and a search for it in whiskey, a two-part wondering about “could we capture something else, something beneficial, something important?”
To make up for too little research in whiskey he turns to the copious literature by grape and wine chemists exploring terroir—“a ubiquitous term in the commercial wine world,” writes viticulture professor Mark A. Matthews in Terroir and Other Myths of Winegrowing, his 2016 scientific examination of the notion. Arnold then ties grapevine berries to grain seeds by way of homology (roughly, as fruit they are impressions of a shared ancestor, comparable to each other the way arms and wings are) and translates the flavor compounds of grape to grains. “Is the grain we use farmed more like table grapes than wine grapes? I’d say yes,” he writes as he moves from thinking of terroir as “the farm that grew the plant” to understanding it as “the interaction between a variety and the farm.” Also ubiquitous in the wine world are the names of thousands of grape species' cultivated varieties—say, Pinot Noir or Catawba—and hundreds of words for the immediate places in which they’re grown, the ever-present site or, digging deeper, soil types and climate. As a replacement for those terms, farm is instead a fundamental meeting place, richer and more generous than the most well-suited soils of any site. Each farm is not just a specific selection of the many choices that make up agriculture, it is also, importantly, a location for those agricultural components and removes the useless transcendence that too easily characterizes the title term. For both wine and whiskey, Arnold’s farm suggests, terroir must mean an address, too—one which can also explain how and why someone is planting grain varieties like heirloom Bloody Butcher and White Sonora, or modern D54VC52 Dyna-Gro or Terral LA841, “named for the seed company that made them” and bred for yield and disease resistance but not for flavor. “The diversity of grain and grape varieties, I realized, was a crucial character in the terroir story,” writes Arnold.
As it builds toward terroir as location-based agriculture, Arnold’s book becomes a confluence of academic research and the haunting what else? scientific literature insists on being left behind. As “terminology” that Matthews ends his book with, terroir is “too nebulous to be useful in any genuine inquiry into what is inside the grape or bottle.” But it’s useful as a skeleton key to all the addresses Arnold visits in pursuit. Alongside exhaustive lists of flavor compounds like the “sweet, green, ethereal” aroma of 1, 1-diethoxyethane, which occurs in both Bourbon and wine; a 13-page lexicon of pre-barrel-aged Bourbon aromas, such as lab-identified fruity-dark, floral, green, and haylike components; multi-page chemical roadmaps of terroir in Bourbon and rye and malt whiskies; pages, pages of sifting through it all in lab-report style—“Looking over [food chemistry professor Peter] Schieberle’s results, the first thing that jumped out to me were the norisoprenoid terpenes, and specifically β-damascenone (cooked apple aroma, or even sometimes described simply as whiskey)”—are the contextual companions usually sorely missed in research literature.
Whiskey terroir context includes the market of soft, grown commodities, the source of most distillers’ raw materials. To map any farmer’s grains onto that market, a governing body (in the US, it’s the USDA) redefines them into sellable bulk by separating farms and varieties into species, grain class, and grade. Those are then stored and sold by grain elevators, huge-siloed facilities that “are not set up to effectively segregate grains.” A distiller who is interested in provenance can source directly from farmers (such unmixed grains are known as “identity preserved,” initially an industry cataloguing response to the arrival of genetically modified versions) or, better still, unite with farmers to support grains grown for flavor. Context includes what Arnold identifies as the US’s first whiskey terroirs, intersections of what grew most deliciously where—the Monongahela rye that northern European colonists brought and planted along the river that runs through Pennsylvania and West Virginia to the Ohio River; Kentucky’s Bourbon Country, seat of lush and plentiful corn first planted here thousands of years ago when the area was still Mexico. Context too is what decisions are being followed or made in the present, and so Arnold heads, chemical roadmap in hand, to rye-growing New York, where US distilling began. He compares its new Empire rye style (made of at least 75% NY rye vs. the industry standard 51% rye from anywhere) to the corn-focused Kentucky whiskey, with its distiller-proprietary yeast strains and water from limestone-bed aquifers. And he travels to the barley farms of Ireland and Scotland to visit others “out there, trying to chart the same map as me,” to see the grains grown, to drink what’s distilled from them.
“My difficulty is not that terroir is of French origin, complex, or difficult to translate, but that its use defies a clear understanding,” Matthews complained. In contrast, echoing non-definitions of terroir but not unhappily, Arnold writes that, “Flavor chemistry and sensory analysis will always present scientific and technological limitations, and therefore the information is to be taken as a guide as opposed to a definitive code… There still is—and I believe there always will be—a hint of wonder and mystery to flavor.” His map includes maker of single-malt Irish whiskey (that e denotes place, too: whiskey is made in the US and Ireland, whisky elsewhere) Waterford, who unlike most distilleries and like many wineries employs an agronomist and distills barley from individual farms separately, and who was also investigating terroir vis-a-vis their distillations. (A research paper Waterford published this February concludes that distilling by barley variety and a single farm “has clearly demonstrated variations in the contribution of… sensory attributes in these new-make spirits; therefore, it reveals a ‘terroir’ effect,” raising the possibility of upcoming experiments such as single-vintage distillations.) “Here I was in the middle of rural Ireland drinking tea and eating scones with fresh butter and drinking whiskey made from barley grown not more than 100 yards from where I was sitting and I was enjoying it with the farmer himself basking in his pride,” writes Arnold of tasting a Waterford bottling. “It was the expression of a very specific place.”
His journey ends on the island of Islay, rich in peat (a decomposed-vegetal fuel that gives the smoky flavor that is part of many Scotch whiskies), and home to a Scotch producer whose idea of terroir includes supporting local jobs by keeping the distillery unautomated, making gin from 22 local botanicals, and growing rye just to see what will come of it (“we don’t even know what we are going to call the spirit made from rye,” the distiller notes, as by law it cannot be labeled Scotch, a barley-based drink), extending terroir to future agriculture, too. And here, Arnold’s dense and beautiful book rests. What has he concluded? “Terroir is the connection between the consumer and the place,” he writes, echoing a moment more than 200 pages earlier that had vitally connected us to wine and whiskey—yeasts and humans, Arnold had written, turn sugar into energy via the same metabolic process. “A whiskey is shaped by the people who make it just as much as it is by its ingredients,” this whiskey-making scientist writes. To make his Bourbon, aged “in our volatile North Texas climate,” Arnold now uses a series of identity-preserved varieties of distiller grains, including a “forgotten Texas heirloom corn, Hillsboro Blue & White,” all grown on Houston black clay soil and stored on a smaller flavor-first scale by a neighboring whiskey-loving farmer who had been wondering the same things.