Minerality: rocks in your wine or rocks in your head?

[Andrew_Harrison]

Minerality. It is a commonly used descriptor for flavours, usually in white wine, and usually those from the northern extremes of wine production in Europe, leading some to say that it might be a synonym for acidity or austerity. Others say the perception of chalky, slatey, flinty elements in wine is conveyed by sulfur compounds, especially mercaptans. The vine selectively absorbs single metallic cations and small anionic compounds, which taste the same – if they taste of anything – regardless of their place of origin, yet some commentators talk as if vines are passive conduits of complex mineral compounds between the soil and the grape giving rise to iron flavours in iron-rich soils and chalky or oyster shell flavours in wines produced on limestone.

What is this thing called minerality? It didn’t appear in wine writing until the 1980s and is still shunned by some. Is it a valid reproducible descriptor or does it mean all things to all men?

A couple of weeks ago I presented a line-up of German Rieslings to the Magnum Society in Wellington and took the opportunity to gather some data on my colleagues’ perception and understanding of the term minerality. WARNING. This is going to get a little geeky, so if you think that wine should be about romance not statistical analysis, look away.

Method: Six 2005 German Rieslings were presented blind. They were as follows: Loosen Erdener Treppchen Riesling Kabinett; Fritz Haag Brauneberger-Juffer Riesling Kabinett; Schaefer Graacher Domprobst Riesling Spätlese; Dönnhoff Norheimer Dellchen Riesling Spätlese; Dönnhoff Oberhäuser Brücke Riesling Auslese; and Fritz Haag Brauneberger-Juffer-Sonnenuhr Riesling Auslese.

The 19 participants were asked to rank the six wines in order of minerality, the “1st” being the “most mineral”; whether that be the “strongest mineral flavour” or “best exemplifying the concept of minerality”, the “6th” being the least. The participants recorded their rankings independently on paper slips, which were collected before any group discussion on the wines took place.

Results: Data on each wine was analysed separately using the Kruskal-Wallis rank sum test (you were warned) to determine whether the rankings were random, in which case minerality would have little value as a descriptor. The p value was 0.00042, meaning that this was extremely unlikely to be due to chance.

Frequency (y axis) of each of the 6 rankings, 1st through 6th, (x axis) for the three different Prädikat levels.

The main finding of the exercise is best demonstrated by comparing the frequencies of each ranking for each of the three Prädikat levels (see figure). This shows that participants more commonly gave high rankings for minerality to wines with low levels of residual sugar, the Auslese wines most commonly getting the lowest rankings.

Conclusion: There was a high level of agreement between participants, indicating that this descriptor is ‘similar things to most men’ (and women of course, although there were too few present for sub-analysis by gender). The tendency to rank wines with lower residual sugar as more mineral that the higher Prädikat wines supports the view that minerality is a surrogate for austerity and acidity, or that minerality is masked by sugar.

References:

1. Minerality in wine: What does it mean to you? - Decanter
2. Minerality and terroir in wine
3. mercaptans and other volatile sulfur compounds in wine
4. http://www.nytimes.com/2007/05/06/style/tmagazine/06tdirt.html?_r=3&pagewanted=1&oref=slogin&

[Anton_D]

Wow!

Thanks for that effort!

I think minerality is a legit sensation. I’d say Chablis does it well. Even La Tour.

Thanks again for that post.

[Jeff_Vaughan]

Interesting post. I suspect minerality can be masked by sugar. For me I often use the terms saline or salinity when I am drinking Chablis, and sometimes crisp Italian whites. I would think that would be hidden in wines with more sugar and weight. I enjoy wines wine saline, slate, flint, stoney notes and higher acid.

[Howard_Davis]

Andrew, interesting exercise and great writeup.

I was at the tasting and my impressions were along these lines.

I know that people I respect like Jancis Robinson have no use for the concept. However I do, to varying degrees, find something I call minerality in some wines especially Chablis and some other Burgundies. I’m not sure if it’s a label, an analogy or an actual chemical property (although, I understand, the last is not likely). I’m also sure reductive elements enhance it and sugar reduces or masks it.

I’d be interested to hear a chemical scientist’s take on this …

Cheers, Howard

[Evan_Pontoriero]

Fascinating stuff. I would imagine sugar overpowers. We are so sensitive to it. I can see austerity driving minerality.

There was a great article in PWV in 2012:
http://www.enologyinternational.com/articles/Minerality_reprint.pdf

Also:
http://www.specsonline.com/pdf/BEARminerality_1.pdf
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=7&ved=0CEQQFjAG&url=http%3A%2F%2Fwww.sommelierjournal.com%2Farticles%2Fsm_2012-04-17.pdf&ei=-pY9VenPGMHooATx6oCoCg&usg=AFQjCNH6X3U5uflbt6vu679yA_bDpUp22g&sig2=Jvovz_JmyQ49FfMKa8wtzA&bvm=bv.91665533,d.cGU

[Andrew_Harrison]

Thanks Anton, Jeff and Evan.

Howard, it might not be that minerality is enhanced by reduction, but rather that minerality is reduction, the perception of which is enhanced by acidity.

That would explain why the archetypal mineral wines are those with high acidity from the band of cool climate vineyards that stretches from Muscadet to Mosel, and why minerality is masked by sugar, which masks acidity.

[Alan_Rath]

Nice work. But realistically, did you expect anything different? I have no idea what causes the sensation we tend to describe as “minerality”, but it is pretty clearly tied to dryness, and acidity in some way, maybe other factors, but those are pretty much “necessary” to find minerality in a wine.

[Wayne_Alleyne]

I’m going with rocks in your head.
I remember the days fondly when we had tasting notes that were not cluttered up with pointless references to minerality. Clearly the aromas and flavours are related to the sulphur compounds, the level of acidity and their interplay in any given wine. I would also agree that reduction and austerity have a part to play. It’s nothing more than a fashion trend that has no basis in fact.

[GregT]

@Wayne Alleyne

I’m going with rocks in your head.
I remember the days fondly when we had tasting notes that were not cluttered up with pointless references to minerality. Clearly the aromas and flavours are related to the sulphur compounds, the level of acidity and their interplay in any given wine. I would also agree that reduction and austerity have a part to play. It’s nothing more than a fashion trend that has no basis in fact.

Couldn’t have said it better.

And the point of the tasting seems to bear that out.

BTW, there’s no reason sugar should mask “minerality”.

[David_Glasser]

Very cool. It seems logical that sugar and sweetness would tend to cover up mi reality, however defined.

But how do we know if the correlation is related to residual sugar (I’ve had Kabinetts that tasted as sweet as Spatlesen) or to some other factor related to ripeness, perhaps alcohol levels?

[g.colangelo]

I am puzzled by the methodology: in general, whenever one wishes to study one issues/factor, one tries to determine how this influences an outcome (whether objective or subjective) all other things being equal. In other words, one would try to isolate the effect of that single factor as much as possible from all the rest.
In this case it is clear that RS plays a very important role, so much so that you will never be sure whether what you “measured” is minerality, or the lack of residual sugar.
IMHO.

[Jon_A-K]

@g.colangelo

I am puzzled by the methodology: in general, whenever one wishes to study one issues/factor, one tries to determine how this influences an outcome (whether objective or subjective) all other things being equal. In other words, one would try to isolate the effect of that single factor as much as possible from all the rest.
In this case it is clear that RS plays a very important role, so much so that you will never be sure whether what you “measured” is minerality, or the lack of residual sugar.
IMHO.

+1. This is an interesting result, but just seems to indicate that residual sugar should be controlled for in the next experiment. Wines with equal RS (perhaps ~zero) could be compared, and then the participants’ rankings could again be tested to see if they correlate significantly. If they do, then it is unlikely that minerality is just dryness, and more potential explanatory variables can be explored.

[RS_Beck]

From my reading, I’m fairly convinced that the taste of various mineral flavors in wine is probably not from actual minerals being sucked up from the roots, deposited in the grapes and on into the resulting wine. So, debunking this idea, to me, is pretty small spuds.

I’m also fairly certain that the classic notes of lead pencil do not come from all of those pencil shavings that must be in the soil in Bordeaux.

So, okay, it’s probably not actual minerals, nor beef blood, nor leather, nor earth, nor pencils that cause us to taste these flavors in wine.

Does that stop anyone from tasting these things? Nope. So, no reason to think there has to be any actual minerals in the wine for wine to taste of minerals. You mean something else besides actual minerals, beef blood, leather, etc. causes us to experience these flavors? Pardon me, but, duh, of course!

Don’t know what minerals taste like? Unless you cannot distinguish regular water from mineral water, I think you may be putting us on. Salt is a mineral. Surely you know what salt tastes like.

In my experience, it’s relatively uncommon for any two people to taste the same flavors in any wine. Peruse the professional critical reviews and you’ll see very little agreement regarding the flavor profiles of any particular wine. So, I think it’s fairly significant that you were able to achieve any consensus from your tasters regarding minerality.

In my opinion, wine tasting notes are about the easiest thing on Earth at which to poke fun. Because anyone writing tasting notes has to take a sensory experience and put it into words. It almost always requires the taking of poetic license, and the employment of similes and metaphors.

Would anyone really want to drink a wine with the texture of velvet? Ever run your tongue across a piece of velvet? So, every tasting note that extols the virtues of a wine with a texture like velvet or silk or, hell, any kind of cloth must be fodder for ridicule, right? How can a liquid have the texture of any kind of textile? Who will volunteer to start the new thread titled, Velvet; the texture of your wine, or the texture of your frontal lobe?

It’s only when you allow the writer some poetic license so he/she can communicate his/her experience in words and imagery that tasting notes make any sense.

Same applies to mentions of minerality.

[Lewis_Dawson]

Rob, excellent post. I agree 100%.

[Lewis_Dawson]

@Andrew Harrison

What is this thing called minerality? It didn’t appear in wine writing until the 1980s and is still shunned by some…

Really? Are you saying that Mosel wines did not evoke slate to wine tasters before the 1980’s? And the same for oyster shells and salinity in Chablis? Then what did Chablis taste like “back in the day?” And the iron nuances in many wines from Morey and Gevrey were also not noticed back then?

Or are you saying the catchall term “minerality” was not in vogue, but other more specific descriptors were used instead? If your premise is that writers today are more vague and lazy, you’ll get no argument from me. But I think you are overstating the concept of minerality as a johnny-come-lately.

[David_Bu3ker]

@Wayne Alleyne

I’m going with rocks in your head.
I remember the days fondly when we had tasting notes that were not cluttered up with pointless references to minerality. Clearly the aromas and flavours are related to the sulphur compounds, the level of acidity and their interplay in any given wine. I would also agree that reduction and austerity have a part to play. It’s nothing more than a fashion trend that has no basis in fact.

And when were those magical days you speak of? Must be more than 20 years ago. The idea of minerality is not a recent thing.

[Lewis_Dawson]

@Wayne Alleyne

I’m going with rocks in your head.
I remember the days fondly when we had tasting notes that were not cluttered up with pointless references to minerality. Clearly the aromas and flavours are related to the sulphur compounds, the level of acidity and their interplay in any given wine. I would also agree that reduction and austerity have a part to play. It’s nothing more than a fashion trend that has no basis in fact.

This comment seems odd to me. You name four dimensions that interact, which makes for a very complex model, but then just drop the subject and dismiss it as fashion.

Part if what makes wine captivating as a beverage is that the subject is complex and nuanced. Wine certainly challenges the limits of human language. When I taste a wine and describe it, I rely upon any tool I can find, but I’m generally not giving an objective chemical analysis. If it tastes of peach and my friends can relate to that, then the descriptor is working. If I find it minerally and my girlfriend understands that impression, then the descriptor is working.

How would a chemist respond if I describe a Vosne-Romanee as rich silk brocade, and contrast it to the gossamer filigree of a sublime Chambolle-Musigny?

These discussions always have someone saying, If we can’t express (minerality - or whatever the topic) as a scientific equation, then it does not exist except as a writer’s fantasy. Hogwash. There are many aspects to wine that science cannot define. IMO it is wrong to say something does not exist just because we don’t understand it scientifically. Also, there are lots of site-derived nuances that are better understood by relatively uneducated vignerons than by scientists. Should we also say these do not exist?

[mike_pobega]

Red wine XXXX XXXX XX
Color: nice
Smell: pretty
Fruit: yes
balance: sure
Tannins: yep
Legs: uh-hu
Finish: 69 seconds

Add a few superfluous words and a score of 1-10 and that is what tasting notes used to look like. Feeling like you’re back in tha 80s? Nothing more boring than old tasting notes.

To those who think wine can’t have: texture, minerality or lead pencil shavings you have been thinking to hard. Relax and enjoy it. it’s ONLY wine.

I like things better today; everything is verbalized in a personal sense. Ever see Gary V. taste a wine? It may be extreme, but there is a whole bunch of people who can relate. Remember, video killed the radio-star.

[DougS]

@Wayne Alleyne

I’m going with rocks in your head.
I remember the days fondly when we had tasting notes that were not cluttered up with pointless references to minerality. Clearly the aromas and flavours are related to the sulphur compounds, the level of acidity and their interplay in any given wine. I would also agree that reduction and austerity have a part to play. It’s nothing more than a fashion trend that has no basis in fact.

Hmmm, aromas related to level of acidity? That doesn’t make sense. Also, why do wines that are strongly mineral always still smell that way when I’ve let them sit 6+ hours in a decanter and swirled vigorously in a glass? Surely you aren’t talking about non-volatile sulphur compounds? If so, which ones? I’ve mistaken sulphur compounds for minerality many times, especially in screwcap-sealed New Zealand wines, but after 30-60 minutes in the glass, they are gone. I guess everyone who thinks they smell something related to stone or chalk in a wine is wrong, thus no basis in fact? That’s something that you couldn’t possibly be sure of. There are no apples in wine either. Is all apple-related aroma also nothing more than fashion with no basis in fact? I’m really not seeing a logical argument here.

[Brian_Tuite]

WARNING. This is going to get a little geeky