Yes–my own conclusion over the years is that most of this is from reductive winemaking rather than any effect of added SO2. I think far too much gets attributed to SO2, even in tasting notes from those who should know better. But on the other hand, I’ve never made a wine in my life (thank god), and don’t really know much about when, where, and how SO2 is used, so it’s entirely possible that I’m totally wrong. Has anyone asked personally or seen discussions with the winemakers involved with the wines that have this classic profile what the origin of this character is?
This is what I’ve always assumed. Alban (back in the day, haven’t had a recent one) was notoriously “reduced” i.e., contaminated with skunky/rubbery sulfur compounds. Lots of winemakers use plenty of SO2, but they don’t get this result.
Benzylthiol, aka benzyl mercaptan, is the cause of the struck match character.
The science-ish gobbledygook reference
or if you prefer the twitter version:
And apparently, struck match is on the way out (for Aussie Chards anyways):
https://www.thedrinksbusiness.com/2017/10/peter-gago-struck-match-is-on-the-way-out/
So there you have it!
Interesting! It might be a concentration thing, together with other compounds, because 2 out of these 3 links suggest it’s more onion/garlic/noxious smell than something pleasant like a struck match:
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I think it’s fair to say there is a wide gap between the precision of a scientific identification of thiols, sulfur dioxide, and other free or bound forms of sulfur-containing compounds in wine and the hand-waving and inconsistent terminology we all use to describe and sometimes muddle our aromatic perception of these compounds in volatile form when smelling and tasting. I don’t think there is any uniformity in how people use the words reduction, reductive, and reduced to describe wine aromas, whether as an ephemeral state of a wine or as a perceived flaw. Threads like this one help to recognize but not resolve the state of affairs.
As to the OP, my perception as also suggested by various comments above, is that these Coche, Leflaive, and PYCM wines all exhibit the effects of both added SO2 (including reaction products over time? Chemists?) and other thiols, like volatalized Benzylthiol, that result from reductive winemaking.
As my questions above suggest, what I’d be interested to understand better from the chemists is whether added SO2 contributes to chemical reaction pathways that generate thiols in bottle or are those thiols solely the result of the winemaking techniques employed prior to bottling.
I’ve read, in a number of articles, that thiols are highly variable/changeable in how we perceive their aromas, depending on their concentration level. So I’m not hugely surprised that Benzylthiol is noxious at high concentrations and is a $1000 bottle of chardonnay at lower concentrations 
Toss a bit into your Chard, and see what you can get for it 
I was wondering where a benzyl compound would come from in winemaking, but apparently benzylthiol is a naturally occurring compound. Now I wonder if it’s something in a particular vineyard, due to soil or microbes? a yeast product? something in the winery, maybe even from how they clean tanks or barrels, treat corks, etc?
Great idea…heck I’ll even mark mine down to $950.
It’s my impression that most thiols are a confluence between grapes, yeast and aging (in the right circumstances & combination)…I’d guess benzylthiol fits in here, but that’s just guessing. Course some thiols come straight from the grape…Sav Blanc and the other ‘thiolic’ grape varieties, so those are a different source…would be surprised in BT was anything like that.
Hey, wouldn’t ‘The Thiolic Grapes’ make a great band name?
Ooh, instead of “reductive”, I’m going to start describing wines as “thiolic”.
O Mercaptan! my Mercaptan!
Very clever, Alan.
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Interesting discussion. I am just getting reacquainted with white burgundies, and opened a bottle of a 2013 Meursault the other night. I sniffed it in the glass and was put off. Definitely not TCA, perhaps light matchstick, but just not right. A bit skunky, not cabbage-like, but not alluring.
I left it in the glass and opened another burgundy, and it was displaying none of this character. I left a glass of the first one open and went back to it periodically, and the off-putting nose subsided a bit, but what got left was almost a non-existent nose, and a palate of sour notes. Not something you want to drink.
I find the number one cause of “reduction” is inadequate air into the must during fermentation. Most wines are punched down or pumped over during fermentation, twice a day. If not enough air gets into the must in this process, I find it goes reductive either at the end of fermentation or soon after going into barrel. With Cab, you can rack a couple of times and usually that will do the job to eliminate it. But since several Pinot and Syrah winemakers never rack at all, they occasionally get stuck with it.
Roy,
Agreed entirely, but I also think a couple of other factors need to be taken into account. With ‘reductive’ varieties like Syrah, you oftentimes can smell the reductiveness during primary fermentation. It is therefore imperative during primary to smell all ferments, but these especially, as you may need to pump over or punch down more often.
Also, I keep my wines on fine lees during aging, never racking until just before bottling - unless things get reductive. Whether correct or not, I feel that the lees help keep the wine ‘fresher’ during aging and help maintain better natural Free SO2 levels. I know that many winemakers do not do this, instead choosing to rack their wines after secondary and then again at least once or more often. I’ve found that this ‘opens a wine up’ just like decanting the wine does - but I worry about somehow reducing ‘ageability’ as you expose wine to air at this stage. I choose to keep my wines ‘tightly wound’ until just before bottling.
Cheers.
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So for someone that loves the matchstick nose on a Chardonnay…anyone got any producers less expensive than Coche that routinely hits that mark??
I typically rack my Cab the following May or June (6 months after fermentation) and then the following January (13 months) and then to tank at bottling with nitrogen or argon, depending on how it tastes, at 19-20 months. The second rack is usually my final blend.
Like you, I like the effect of the finer lees. I figure if the lees tastes good, the wine tastes good. If I am reductive by the time I finish malo, I might be tempted to rack, but I try everything I can to avoid reduction early in the process now.
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So, to recap, reductive aromas in wine don’t have anything to do with SO2 additions. Is that what the educated heads around here have concluded?
One can think of it as a continuum from reduced Sulfur to elemental Sulfur to oxidized Sulfur. While proposed as theoretically possible to have occur during fermentation, I was taught that the yeast are not taking the oxidized Sulfur (SO2) and making H2S. Does anyone out there know differently? The yeast are taking the SO2 (or SO3-) and slamming an acetaldehyde group onto it (an intermediary compound on the way to converting the six-carbon sugar into two CO2’s and two ethanols), thereby neutralizing it, shunting it aside, which is why there is no measurable free SO2 in the wine after primary fermentation, which is why the malolactic bacteria are not inhibited from starting fermentation.
The H2S produced during fermentation will readily combine with any number of carbon-containing compounds which is why there is confusion in characterizing exactly what that reductive smell is like – there are a range of different compounds in different quantities in different wines. We used to use “R” to stand in for any of these mostly carbon based substrates, describing H2S as becoming HSR. I think a good rule of thumb is that the shorter/smaller compounds are “sharper,” (think rotten eggs) and the longer chain – yeast autolysis products for example – are more subtle, like toasted brioche. And certainly without the yeast there really is no likelihood of SO2 e.g. added before bottling becoming HSR.
Now, we do use elemental Sulfur in the vineyard, and though with heat/sun/time it tends to volatize away well before harvest, if it does get into the fermenter it will most assuredly be a source of H2S produced. In other words the yeast will take S and make H2S. In other cases, the yeast are finding the juice/must deficient in certain amino acidsn (this is the most common case). With Syrah yeast just seem to want to make reduced Sulfur regardless! Pumping over (or racking) to allow the fairly volatile compound H2S to escape works as long as you can get rid of it fast enough. There also appears to be a benefit to the yeast of pumping over as they receive oxygen during fermentation which prevents the formation of H2S.
As for white Burgundy, H2S produced during fermentation (having nothing to do with SO2 added before bottling) is the source of the burnt matchstick and other compounds, but which ones will have which HSR compounds is hard to predict, influenced largely by winemaking practices in response to grape/vine nutrition. So trial and error, friends – producer, producer, producer!
Nick, thanks for chiming in with that useful info. For the record, I’ve made no claims about how mercaptans end up in wine, just how to (and how not to) describe a wine that has them. And to not describe a wine that has obvious SO2 in the same way. But I recognize that my ranting is swimming up a fast stream moving against me.
On the latest “I’ll Drink to That” podcast you can hear Ehren Jordan wax on poetically about reduction in winemaking. My favorite thought expressed, to the effect of “Racking is like pornography, I’ll know when to do it when I see it”,
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Chris Camarda from Andrew Will used to have copper stir sticks for reduction. If you think a wine is reduced stir it with copper, not a penny, but copper. If its sulfur the wine won’t change.
Great lesson from a good friend with a wine shop on Queen Anne in Seattle years ago.
This for me as well. ^