Olivier Humbrecht on minerality – part two
Olivier Humbrecht
In part one of his presentation on minerality, Oliver Humbrecht said what minerality is not, and explained the need for a soil full of microbial life to bring the mineral fraction into contact with the organic fraction of the soil. Plants need minerals to grow properly.
Will this mineral fraction give a taste to the wine? “I can’t answer that” he said “this is a subject for the next few decades. It’s very hard to say that because your soil has this mineral fraction, its wines will taste more complex.”
However, “finding a wine with a high mineral content is always a sign of a soil that functions properly and a sign the vine is capable to transfer these minerals from the soil.”
Humbrecht explained that the extraction and transfer is done by different microorganisms in the soil. “A vine that has a high mineral extract also has mycorrhizae on the roots functioning perfectly, able to absorb those minerals.
“So minerality in a wine is a sign that the vine is working properly. But it’s a dangerous statement to [suggest] minerality affects the taste of the wine in terms of flavour. We don’t have the research to clarify that.
First steps, he said, are that “you must learn to recognise minerality on the palate. This very small amount of minerals may not smell of something, but they will taste. Very often it’s associated with acids in the wine especially tartaric. And it will modify the structure of wine in terms of acidity, pH, salinity of wine. A wine with a high mineral content, with lots of ashes, will for sure be a wine that makes you salivate.”
Part of this learning is to avoid confusing “true minerality or true salinity with green acidity. People have to learn how to distinguish. A big mistake is to confuse unripe characters with actual salinity/minerality.”
Root activity is key to understanding minerality, he said. “Everything in non-organic cultivation favours the development of the green parts of the plant [branches, leaves]. It neglects the root activity and flowering process.” So when you increase the vegetative part of the vine by augmenting photosynthesis, you diminish the importance of root activity and dilute minerality.
Checking to see if a vineyard is managed properly can be done by digging a hole and cutting a piece of fine root. Under the microscope, Humbrecht said “in vineyards with good organic metabolism, you find lots of mycorrhizae, like a veil of white mushroom filaments. These mycorrhizae are in symbiosis with the roots, using vine sap to satisfy their own sugar and carbohydrate needs. And they help to degrade the soil around the roots, liberating minerals” in this zone.
But when mycorrhizae are not working properly, for example where soil is compacted or where chemicals have been used, he said, fertilisers are needed so vines get the minerals they need.
Whether your mycorrhizae are working properly or not, all soils are not equal in the minerals stakes. “Not every soil has the capacity to produce high quality clay” he said “and therefore have the capacity to fixate minerals in the soil.
“You can measure the mineral capacity fixation ratio. It depends on the capacity of the mother rock to degrade into particles small enough. Limestone, calcareous [soil], schist, marl, ferruginous clay and basalt are all soils that have this capacity to produce these interesting elements. But some soil types do not have the capacity to produce minerals and these are usually sandy soils, sandy loam, silt, gravelly soils that are not mixed with marl or richer content.”
Grape varieties, too, can influence the sensation of minerality. Humbrecht said “probably there is an inference that varietal aromatics of a wine can hide minerality. I often say that minerals don’t smell. But some aromatics are often associated with a mineral quality. For example iodine is a volatile compound so you can smell iodine. If I smell iodine it brings a notion, an association, of minerality to my mind. But you have to teach your brain not to fall into certain traps, the most common one is not to associate reductive character in wine with minerality or unripe character such as high malic content.“
On the question of high alcohol and lots of new oak, Humbrecht said “anything that detracts from the fundamentals of the wine may hide the minerality. New oak, a very aromatic grape variety: for example many people say riesling is more mineral than gewürztraminer but this is because we look at things from the aromatic point of view. Yet once you dissect the taste, not the flavour, on the palate, you understand what makes you salivate. It’s a tasting exercise.”
He reiterated “minerality is not acidity. Acidity is not minerality”. However biodynamic practitioners report a rise in analytical acidity, anything from 0.5g/l to 2g/l, though it’s still not fully understood why this happens. Humbrecht did say “wine is based on tartaric acid, a strong acid, with two acid radicals which each can combine with minerals. [Biodynamic growers] have seen a change from malic-dominated wine to tartaric-dominated wine, and tartaric acidity is capable of fixing more minerals which are in the wine.”
So minerality is by no means a preserve of biodynamic producers, but the inference is that they get more of this elusive palate sensation.
Comments
2 Responses to “Olivier Humbrecht on minerality – part two”
March 6, 2012 at 9:46 am
Dear Sally,
I have just finished the Diploma at the WSET and am now doing their Unit 7
Course (which is described as the Honours extra course) via the Wein Akademie in Rust Austria.
I decided to write about Minerality in wine as it has been a personal source of annoyance – when wine critics started saying that they could taste flint in wine stemming from the flint nodules in the soil/terroir. Unfortunately I am a lapsed Biochemist
who gave up the white coat to become a lawyer, and I remember enough from my studies to know that life isn’t that
simple!
Anyway, you have written quite a few articles on this subject. I am curious, did you chose this subject
because you dealt with it as part of your master of wine studies? Secondly, I am curious, do you ever use the
expression in your own tasting notes and if so, is it a flavour descriptor or an aroma descriptor (or both) if you use
it at all?
I have been trying to see which wine critic first coined the word as a descriptor in the English speaking
realm. I know that comment that the french were using it in the 80s, but I am almost sure it was not a “Decanter mafia”
word in the 70s and not used in the early to middle 80s either. That probably leaves the 90s as the likely decade.
Have you any ideas as to how I could track down who first used the word in a publish article in the UK?
best regards
Graham
March 6, 2012 at 11:03 am
Hi Graham,
Thanks for the post. I’m drafting a considered response for you and will send. See comments on this piece http://www.winewisdom.com/articles/techie/minerality for part answer to original use.
Sally