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The question
How can wine taste like stone? Are wine writers spending too much time in gravel pits? Or getting "stoned" on something more potent than chardonnay?
The answer
I speak for myself alone and solemnly declare I have not engaged in behaviour that, were I mayor of a large city, would land me on Jimmy Kimmel Live.
So, let's talk about gravel pits. You nailed it with that one. Many wines can conjure a memory of proximity to a quarry, assuming you've stood in such a place, as I have. (I highly recommend the Carrara marble quarry in Tuscany; taste the local sangiovese and inhale dust from the same outcrop that produced Michelangelo's David, an awesome experience.)
To a home-renovation contractor, certain wines might even suggest drywall or plaster dust. Sometimes I get a sensation, both textural as well as olfactory, of chalk, more specifically the dust I inhaled while scrubbing blackboard erasers for Miss Wilks each day after Grade 5 class. (I was in love with the teacher, which may partly explain my passion for chalky wines today.)
You need not have munched on marble or drywall to grasp the concept. It's a smell more than a flavour, but in the field of human sensation, aromas and tastes roll into one. Nasal passageways are responsible for sensing virtually all the thousands of "flavour" nuances in food; the tongue directly perceives only five (possibly six, according to some research) tastes.
Flint, wet stone, chalk, limestone, slate, graphite – various rocky words get trotted out with increasing frequency today in the context of such wines as riesling, chardonnay (especially Chablis), sauvignon blanc and fine red Bordeaux. The wine-geek catch-all is "minerality," which is always used in a laudatory way. It's purely a metaphorical conceit, though, as I've stressed in past columns. The mineral content in wine is well below the threshold of human perception, as rock scientists declared years ago at a meeting of the Geological Society of America.
"Minerality," although a useful term for conveying suggestions of flavours, textures and aromas, should not be taken literally. As several geologists have stressed to me, vine roots simply are incapable of extracting aromatic compounds from hard rock, let alone transporting them directly to grapes. That's just not the way plants grow, despite romantic wine-geek notions to the contrary. Stone in wine? It's blarney.
Where do those prized flavours come from? The jury's out. I speculate it's a combination of natural grape acidity and tangy sulphur-bearing compounds produced by yeast during fermentation. Isn't it curious that nobody ever declares to have detected a mineral taste in fresh grapes? People only find it in wine, which is odd given that fresh grapes are a few steps closer than wine to the soil. That's why I put my money on yeast.
Want to taste "minerality"? Two suggestions among my reviews this week offer a sense: a New Zealand sauvignon blanc and a sparkling white from the Loire Valley.
The Flavour Principle, by Lucy Waverman and Beppi Crosariol, was named best Canadian Food & Drinks Book in the 2014 Gourmand World Cookbook Awards. Published by HarperCollins.
E-mail your wine and spirits questions to Beppi Crosariol. Look for answers to select questions to appear in the Wine & Spirits newsletter and on The Globe and Mail website.