Issac Newton described time in absolute terms that I find intuitive. It is the same everywhere, it has constant duration, and it flows continuously in the same direction. According to Craig Callender, Professor of Philosophy at University of California, San Diego, Newtonian time is a kind of master clock that carves our world into instants.
Over the past century, however, physicists have slowly chipped away at Newtonian time, so that most are now prepared to accept a timeless universe. Atomic clocks placed at the foot and summit of Mt. Washington do not give the same time 24 hours later. Experimental evidence from quantum mechanics has demonstrated that the future can influence the past. A single event is perceived as occurring at different times depending on the velocity at which an observer is moving. Stripped of these core features, is time nothing more than an illusion?
While physicists debate the existence of time, agricultural scientists have long argued about the existence of terroir, a term that describes site specific influences on how we perceive wine. The most recent attack comes from University of California Davis professor, Mark Matthews, in his recent book Terroir and Other Myths of Winegrowing. Professor Matthews offers a comprehensive synthesis of research on the interaction between soil and grapevines, and finds little to support the notion that soils or other features of terroir contribute any unique qualities to the wines grown in them. In a way, it’s comforting to hear, again, that fine wine can be grown on many different soils. Winegrowers in a new region like the mid-Atlantic will find it good to hear there are no innate barriers to greatness.
Still, while a terroirless world may be easier to accept than a timeless world, both contradict millennia of recorded human experience. We can all agree that a Cabernet Sauvignon from the Medoc and one from Napa Valley taste different. Likewise, Sauvignon Blanc from the eastern Loire and New Zealand taste different. There are, of course, many factors that could explain these differences, such climate and weather, and vineyard and winemaking practices. That said, even within our own vineyards at Dodon, the taste of Merlot grown on the clay/gravel soils of Block 21 differs from the taste of the same clone grown on the sandy loam of Block 28, despite similar treatment of both in the vineyard and the cellar. It seems logical to conclude that something about the soil – its composition, structure, aspect, drainage and water retention properties, and microbial flora – has had an influence on the way in which the wine tastes.
The challenge with Professor Matthews’ thesis is that he attempts to answer the big question about terroir without clearly defining the outcome. To be fair, we don’t know a great deal about what to look for, but there are some common themes. Wines grown on chalk or limestone soils, as in Chablis for example, tend to exhibit a sensory characteristic known as minerality. If minerality is caused by this soil characteristic, then we would expect to find it in wines grown on similar soils. This is exactly what we find at Dodon in those parts of the vineyard planted on soils with layers of weathering oyster shells that share mineral characteristics with limestone. There are other wine characteristics that also seem to correlate with soil properties. Wines grown on clay tend to have a sticky quality on the palate; likewise, those grown in loam can have a powdery feeling.
Instead of looking at these sensory attributes, however, researchers have assessed far cruder outcome measures related to fertility, plant growth, and ripeness. As Matthews points out, grapevines grow well even when raised in a soilless environment, but this doesn’t mean that wines grown in diverse soils all taste the same. Although plant and fruit characteristics are not the outcomes of interest when asking about terroir, even using these crude measures, the studies seem consistent with an effect of soil properties on wine. Water restriction, whether through deficit irrigation or natural drainage, results in more color. Nitrogen availability is loosely associated with yeast metabolism and production of aromatic molecules during fermentation.
There are other flaws in Matthews’ arguments against terroir, some of which are simply unrelated to the core question he sets out to answer. For example, he points out that for most of the recorded history of winegrowing, terroir and its related tastes – goût de terroir if you will – had a pejorative connotation. Terroir wines were considered of lower quality, perhaps because of poor sanitation in the cellar that led to infection with brettanomyces, a yeast that gives wine a barnyard-like aroma. This historical view is interesting, but it is irrelevant to any rigorous understanding of the effects of terroir on wine. The same might also be said for his argument that terroir is nothing more than the invention of Burgundian marketing departments. And some of the arguments seem pointless. Although wines grown in various places can be distinguished by their mineral content, it would be silly to believe that flavor molecules are transported directly from the soil to the wine, so why spend the reader’s time rebutting them.
The idea that both time and terroir are illusions rests on the absence of evidence that they really exist. In both cases, human experience tells us otherwise. We perceive that time flows from past to future, serves as a useful measure of things like the duration of events and speed of a car, and allows us to get to appointments as scheduled. Our palates tell us that wines differ when grown in different places. The purpose of science is to explain our observations, so I’m confident that the scientists will eventually find the reasons for the discrepancy between their current research findings and our holistic experience. No fanciful belief in astral powers is required. In the meantime, the mysteries of both time and terroir are intellectually intriguing and fun to debate, so I plan to keep my watch handy and not miss tasting time.