Caution, this article contains some nerdy information!
Okay, wine descriptions can be tricky, right?
If you are new to the wine world, it might take some to figure out how to express your thoughts without making a fool of yourself. There is a thin line between using creative descriptions and babbling. So here is a hint for you. Nobody really cares if you smell peaches and other insists on pears as long as it’s logical. In the end, wine tasting notes are metaphorical.
However, there is one aspect that has created a huge debate lately in the wine world: ‘minerality’. When wine lovers buy a wine, which is claimed to be mineral, they naturally assume that there are minerals in the wine that creates a certain smell or taste coming from the minerals in the soil.
Well, this does not seem to be true.
Few months ago, I’ve attended Imbibe Live in London and had the luxury to attend Prof Alex Maltman’s workshop on this subject. Here is a short summary about the science behind it:
So, we all know that vine roots take the essential minerals from the rocks and soils. Therefore, it makes sense to think that the vine transfers these minerals to the grapes and eventually to the wine. This creates a direct link between the geological minerals and nutrient minerals in the wine. Wine marketers love this link as it promotes the idea of a unique parcel / vineyard.
Let’s have a look at what actually happens. The nutrient minerals in the wine and geological minerals (minerals in the soil) are linked, but they are not the same thing. Nutrient minerals in wine exist in ionic forms, as cations such as Ca++ or Mg ++. However, in soil, geological minerals are all complex compounds and although they are the major source of nutrient minerals, the process is quite complex and depends on many variables. Once the roots absorb nutrient ions, they are distributed to different parts of the vine. Some of them reach the grapes and different proportions end up in skins, seed and juice. Moreover; fermentation, filtration, fining and ageing processes can also remove or add nutrient minerals. So the direct link between geological minerals and nutrient minerals gets weaker and weaker. And the reality is, minerals do not really have any flavor at all. Licking a rock may give a certain sensation but that’s not a taste. Take slate or quartz, the difference cannot be recognized by tasting them blind, as they are insoluble and do not volatilize. And even if they had a taste, the concentration of mineral elements is way too low in wine to recognize. Very few minerals are noticeable above a certain threshold but this is not possible with the amount available in our glasses.
Now, all this information sounds valid and logical, right? But what do we do with hundreds of tasting notes written for Riesling, Mencia or Assyrtiko that mentions minerality?
Well, because we are all very curious wine students, we try to understand the real reasons behind a certain smell or taste. Alex Maltman gives examples of common tasting notes of minerality. Flinty for instance is used a lot, especially for Riesling. Flint is actually a form of silicon dioxide and it’s flavorless. 2-methylisoborneol from algea explains the earthy smell; geosmin on the other hand is due to bacteria and so on.
But let’s be careful. Nutrient minerals do contribute to wine flavor in another way. Tiny amounts of inorganic ions influence acid buffering, metabolic catalysis, act as enzyme co-factors and more. It’s just not as simple as its thought because geological minerals and the mineral taste in wine is not directly connected. So sad news for marketers who differentiate certain wines directly related to soil… (No worries, creative marketing people do not rely on one USP!)
The scientific background of this subject does create a debate because many winemakers believe in the link of a certain type of soil resulting in some sort of mineral taste in regions such as Mosel, Priorat, Chablis…
From my perspective, I do understand that chalk or slate soil can result in different styles of wines for many reasons (this is another topic to discuss the influence of soil in wine), but there is lack of evidence that the wine has a mineral aspect due to the soil.
For me, what matters is clear communication among wine lovers and professionals. I have doubts about the use of terminology. If one says mineral, do we all imagine the same thing? I don’t think so.
I believe that it is cruical to understand that we don’t actually taste the minerals coming from the soil. We can describe the wine as “mineral” considering that it is a metaphor just like other tasting notes! As other wine professionals also advice, it is a better idea to elaborate and use terms such as chalky or stony to explain ourselves better. Otherwise, it turns into a game in which we think we understand each other, but we are quite far from it.
As George Bernard Shaw says:
" The single biggest problem in communication is the illusion that it has taken place."
Reources: Presentation of Prof. Alex Maltman at Imbibe Live
To learn more about the subject, check out the articles of Jancis Robinson, Jamie Goode, Alex Maltman