Rocks in the glass

Friday, 16. December 2016 - 12:15
There is a word whose use is causing growing unease among the wine community, and that’s ‘minerality’. Once upon a time the term was the darling of the wine press. Today, it has become an outcast, with some fearing that they will have to issue an apology for using it and abbreviating it to the ‘M-word’.   
This backlash against minerality has been coming for a while – particularly since Professor Alexander Maltman, a geologist from Aberystwyth University in Wales, demolished the concept in a 2013 article in the Journal of Wine Research, in which he said, “Whatever minerality is, it cannot literally be the taste of minerals derived from the vineyard geology.” But the use of the word continues apace, with more than one million references on Google. Dr Richard Smart, a renowned viticultural consultant, is damning in his assessment of the term, claiming that it should be classified “as romantic and tenuous” and is a “deliberate method to mystify wine”.
Consumer appeal?
Certainly, consumers are mystified by this whole thing and it appears they wouldn’t lose sleep if wine writers, producers, marketeers and retailers abandoned the word. Professor Pascale Deneulin, a researcher at Changins, Switzerland’s national wine centre, has found that the term is hardly helping the industry to sell wine. A slide presented at the 2016 Villa d’Este Wine Symposium quoted one of the 1,697 consumers questioned: “[it’s] not attractive… I get the feeling they’re trying to sell me water.” She also found two distinct groups of consumers – those who liked what were deemed as mineral wines, and those who didn’t.
When it comes to wine professionals, they seem to be equally confused in the absence of any rock-solid science. Dr Jordi Ballester, a Spanish oenology researcher now working at the Université de Bourgogne, asked 34 Burgundy winemakers to explain what they thought minerality was. “It was everything and anything… Experts have serious consensus issues when assessing minerality sensorially,” he told the Institute of Masters of Wine Minerality Seminar, held this past October. His point was well illustrated when some of the best palates in the world became laboratory rats – asked to rate a line-up of wines based on perceived minerality, there was little consensus. 
But there must be something in this term for it to go from zero (minerality is notably absent on Ann Noble’s Aroma Wheel and in Émile Peyanud’s work) to hero (and maybe zero again). There is a perception among the wine community that the word ‘minerality’ does describe something that’s going on in our mouths that chemistry hasn’t yet identified. Dr Wendy Parr, a sensorial scientist at Lincoln University in New Zealand, who often works with Ballester on minerality research, has also been trying to understand such perceptions. “There is something in wine driving it,” she says, although “we need to be cautious in how this term is used.”
What is it?
There are various hypotheses about its source. Is it acidity? Could it be sulphur compounds (there is a correlation in the timing between the rise of the word and the use of screwcaps)? Or is it a word that we use when no other descriptor for the wine comes to mind? Professor Hildegarde Heymann, a sensory researcher at University of California, Davis found a positive correlation between the perception of minerality and higher levels of acidity in wine; Deneulin also reports that wines perceived as having minerality were found to have higher levels of malic acid, higher carbon dioxide, and higher free SO2 levels. But other studies haven’t found any interdependence.
Yet, there is something in wine that has caused the wine community to start using this ‘M-word’, particularly for high-end whites from cool climates. Without the science to accurately pinpoint what it is, the riddle remains unsolved. Perhaps it is better not to know, helping to preserve the mystery and romantic allure of wine. What geology has been able to prove, according to Maltman, is that the sensation of tasting flint or wet stones does not come from the vineyards – it’s a metaphor. “It offers a marketing opportunity and it’s a lovely story, so I am sorry to spoil the fun but from a scientific point of view, it won’t work,” he says. And, from a consumer point of view, it doesn’t seem to be working either.
Rebecca Gibb MW