The reality of Minerality in wine
The use of the word minerals and minerality in tasting notes has exploded the last 20 years. But what does it really mean? Is it used by everyone in the same way, to describe the same thing? The use of minerals in tasting notes started to appear in the mid 1980`s, so it is a fairly new descriptor. Minerals are often used to describe wines from the old world, particularly wines from Germany, France and Italy. So why has it become such a common descriptor in only a couple of decades? And what is it?
The most famous theory surrounding minerals in wine
The most famous theory surrounding minerals in wine are based on the fact that the roots of the wine consumes the minerals directly from the soil in the ground. The minerals are then consumed by the plant and then transported into the grapes.
A new controversial theory
A new controversial theory however, suggest that it has nothing to do with the minerals in the soil at all, but in fact bacterias. Local bacteria in a region defines the taste of the wine, giving it a locality and sense of place (Terroir if you prefer).
It all happens in the cellar
Other theories support the fact that the notion of minerality is simply a product of the winemaking process and nothing else. It all comes down to either the presence of So2 in the wine or something called reduction. Both of these can give aromas of flint and struck matches in varying degrees. Reductiveness appears in a wine when the winemaking process allows for a very low oxygen contact. Too much can give foul aromas of rotten eggs, but in small amount it brings a layer of complexity to the wine. A complexity often described as minerality.
Minerals in tasting notes
Stephen Spurrier from Decanter Magazine use the expression minerality to a great extent in his tasting notes. He associates minerals with a stony sensation that appears in his mind when tasting a wine.
Jancis Robinson on the other hand is much more careful with the use of the word minerals in her tasting notes. She prefers to use words like "wet rocks" and "slate", but when she is not sure which group to place the aroma in, the uses the word minerality.
The entire wine business is even divided in terms of the usage of minerals in red or white wine. Some feel that it can only be used as a descriptor for white wines, while others completely disagree because red wines from Volcanic soils clearly has mineral traits in them.
Different meanings of minerals
People can't even seem to agree on the meaning of the word. For some it is a flavour sensation of saltiness and prickling on the tongue. Others completely disagree and describe it as a savoury aroma on the nose.
At the end of the 20th century a German scientist by the name of Andreas Peuke did a test where he planted Riesling in three different pots with different soils (Loess, Muschelkalk and Keuper). After some time he collected the resin from the plants, analysed them and compared them to each other. To his surprise there was huge deviation in the nutrient levels in the three plants.
A Californian wine grower by the name of Randall Grahm also wanted to "play around" with the concept of minerals in wine. He did a fairly straightforward test by putting rocks in the tanks to see how it affected the wine. His conclusion was that the rocks altered the wine to a great extent. He could see great changes in the aromas and mouthfeel of the affected wines. He felt that the wines had gained a higher degree of complexity and density. He also concluded that the colour of the wines glowed very differently from the other wines.
It is easier to define what minerality is not, instead of trying to define what it is. Minerality is something that does not fit any of the common aroma descriptor groups, groups like fruit, spice, oak, herbal, age etc. It is something entirely different. Scientists however have measured minerals in grapes and they have concluded that the amount is so small that the human nose is unable to detect them. If this is the case, one might wonder what the origin is. It is more likely that minerals is either a product of the winemaking process, or the presence of different bacteria which sheds a whole new light on the subject.
Sources: Decanter Magazine, Winefolly.com, David Bird: Understanding Wine technology, Jancis Robinson, Jamie Goode: Wine science
Marius has worked in several parts of the wine business for the last 16 years. He is currently working as a Category Coordinator for wine and spirits in the Travel Retail business. He is also a part of a tasting panel for the financial newspaper in Norway and writes articles and lectures in his spare time.Marius has a huge passion and dedication for the wine and spirits industry. He is a certified Sommelier and is currently undertaking the WSET Diploma in wines and spirits education.