Is it okay to talk about terroir in terms of minerality?

From the chapter: Terroir in peril

Is the fabled minerality of white wines grown in France’s Chablis AOC the result of soil or climate? (Answer: Both).

When you become a working sommelier and are privy to tastings of wines from around the world, you invariably develop an increased appreciation for wines tasting distinctly of their “sense of place”—commonly identified as terroir. The recent obsession with concepts such “balance” in lieu of sensations associated with oak, overripe fruit, alcohol or other excesses is, in one sense, really an expression of our longings for wines that taste more of vineyards or terroir, rather than manipulations thereof through the heavy handed (even if good intentioned) intervention of winemakers.  

I have always thought of terroir as like a tree falling in the forest. Just because you can’t hear it, it doesn’t mean it didn't happen. As subtle as terroir related sensory delineations can be, they often aren’t. A Chablis, for instance, is clearly far less weighty than a Puligny-Montrachet, even though both are grown in Burgundy and made from Chardonnay. The difference between a Chablis and Carneros grown Chardonnay is even more graphic—more acid, less alcohol/body, and far less tropical fruit aromas in the Chablis. The impact of terroir—entailing everything defining a vineyard or region, from soil to climate, aspect to temperature, altitude to latitude, viticultural decisions to winemaking practices, et al.—can be so big, wines made from the same cultivars often barely resemble each other.

But what of wine aromas and flavors commonly associated with regions and vineyards that are usually described as some kind of minerality? Chablis is commonly associated with sensations such as chalkiness, Pouilly-Fumé by a flintiness, Savennières by a somewhat loamier flintiness, and Mosel-Saar-Ruwers by an entire range of sensations suggesting slate or flint. In the past, these would all be examples of wines with characteristics traditionally attributed directly to components contained in the soils in which they are grown. 

“Bullshit,” I once heard Santa Barbara’s Peter Cargassachi say, “vines do not have the capacity to uptake the taste of minerals through root systems... that’s been proven over and over again.” I cannot disagree with that. We all know, or should know, that aromas and flavors of wines are not directly related to biological components found in soil. When you describe a Riesling as flowery, a Chardonnay as tropical-fruity, or a Zinfandel as peppery, it doesn’t mean there are flowers, mango, papaya or peppercorns growing under the ground among the vines, directly effecting the taste of resulting wines. By the same token, mineral sensations in wines do not come from minerals in the ground. But if this is so, where do sensations of minerality come from?

Harrowingly steep, reddish slate terroir specific to the Mittelmosel’s Urziger Würzgarten.

In a piece by Jordan Ross called “Minerality, Rigorous or Romantic?” published in Practical Winery & Vineyard Journal (Winter 2012), scientists such as Alex Maltman (University of Wales), Anna Katherine Mansfield (Cornell Department of Food Science) and Carole Meredith (UC Davis Department of Viticulture & Enology) were all quoted to say basically the same things: Tiny amounts of dissolved ions are typically absorbed by vine roots, but none of them are of sufficient enough efficacy to contribute to actual sensations of minerality in a wine’s aroma or flavor.

But it is no coincidence, Ross explains, that sensations of minerality also happen to correlate with wines grown in colder climates—wines, as such, retaining higher natural acidity. In his article, Ross cites Grégoire Pissot of Cave de Lugny in Mâcon as saying, “’Mineral’ is, at times, used when ‘acid’ would be more appropriate.” The Mosel’s Nik Weis concurs, drawing attention to the fact that, although grown in similar gray slate, a higher acid Ockfener Bockstein will always taste more minerally than a lower acid Piesporter Goldtröpfchen, most likely because Goldtröpfchen is a warmer site and typically a little less acid driven.

Still, as sommeliers we know that minerality is not an abstraction—we can taste it. An Ockfener Bockstein, for instance, retains mineral notes that are slightly different from that of nearby Ürziger Würzgarten. The question is, are the differences logically attributable to the high iron content of Würzgarten’s red slate slope, as opposed to Bockstein’s gray slate and sandstone? Würzgarten, after all, does not translate as “spice garden” for nothing. 

Whether or not the differences among Germany’s great Riesling growths are directly related to variations of aspect, slope, soil, or any number of topographic factors that influence grape expression, the fact remains: Under similar cold climate conditions, the minerality of a Bockstein is different from the minerality of a Würzgarten; just as both taste different from a pungently minerally Maximum Grunhauser Herrenberg, and the oft-times dramatic, pervasive earthiness found in Rieslings grown in even warmer sites, such as the Rheinhessen’s Nackenheimer Rothenberg or the Pfalz’s Forster Ungeheuer. 

Yet the connection between minerality and acidity make sense. Once, in the early 2000s, I spent a day studying Chardonnays grown on four different slopes in the immediate vicinity of Thomas Fogarty Winery & Vineyards, 1700 to 2000-ft. up in the Santa Cruz Mountains.. All four vineyards were planted in the early 1980s on identical trellis systems, and all to Clone 04 Chardonnay (California’s most ubiquitous selection, known for its tabula rasa amenities).

The differences between each of the Thomas Fogarty Chardonnay blocks is defined by their aspect, or direction in respect to sunlight, which impacts fruit ripening. No question: Across multiple vintages, Fogarty’s two coolest, slowest ripening sites (Portola Springs and Albutom Estate) consistently taste more minerally—like the common taste of “wet stones”—than the two warmer sites (Langley Hill and Damiana Vineyard) which see more afternoon sun. Higher acid sensations also correlated with increased minerality. Moreover, the more a Fogarty Chardonnay tastes of ripe, sweet toned peach, pear or apple-like fruit, the less minerally the profile.

Epoch Wines winemaker Jordan Fiorentini in Adelaida District-Paso Robles hillside vineyard characterized by blindingly white calcareous soils.

Then there is the consistent inverse relationship between high pH in soil and lower pH in wine, which is another reason why wines grown in more alkaline, calcareous soils are often associated with increased minerality. Nonetheless, warmer climate wine regions that have calcareous soils with off-the-charts alkalinity, such as much of California’s Paso Robles AVA, are not nearly as closely associated with wines replete with minerality as colder climate calcareous terroirs such as those found in France’s Burgundy, Champagne and Loire River Valley. Climate clearly trumps soil when it comes to higher acid wines with actual imprints of minerality.

Still, as difficult as it is to prove direct connections between minerality and soil composition, there will always be hard working vignerons who will vouch for it. Willamette Valley’s Ken Wright, for instance, is as respected as they come. He says that it is precisely because there is a “symbiotic relationship” between positive microorganisms in soils and healthy plants that there is a direct contribution to wine flavor from soil via root systems.

“As someone who has planted many vineyards over the past 40 years,” says Wright, “I can say that without question, when vines roots reach the mineral rich parent material something wonderful happens.” Wright’s conclusions are based upon his own lab reports tracking soil composition as a result of farming improvements documented over several decades. He finds that the higher the uptake of ionic minerals through enhanced root systems, the higher the clarity of resulting wines. “Wines from these vines go from being muddled and indistinct to having recognizable, crystal clear aromatic and flavor traits.” In this case, however, Wright is not talking exclusively about sensations associated with minerality. Instead, he cites multiple aroma-related flavors such as “chocolate, tobacco, anise, or cola,” on top of “increased profiles related to iron/stony qualities, which remain consistent from year to year.”

Or are we overthinking this? In my experience with the better winegrowers over the years, they seem to know their wines like mothers know the smell of their babies. As sommeliers, would it be wise for us to question that?

No question, site matters. After that, it's a matter of interpretation and individual circumstance..