750Daily: Sulfites & WineChemistry...Understanding Metabolomics

A rather interesting article in 750Daily, as linked by WineTerroirist:
750Daily:Sulfites&WineChemistry .
It’s a pretty generalized article and rather short on specifics. But it does introduce us to the term “metabolomics”. Metabolomics is a technique to provide a detailed map of all the chemical compounds present in the wine. It appears the timing of the SO2 additions are very important on the ultimate sensory characteristics of a wine and that a wine remembers this timing of SO2 additions. This is, of course, the kind of stuff that drives SweetAlice apoplectic…you don’t use SO2 additions in making real wine.
I can hardly wait to being in a gathering of wine geeks and toss out the term “metabolomics” and watch them all nod in knowing agreement so they don’t appear ignorant!!
Tom

I’m getting a headache. . .

Have some dried fruit.

If I may expand on the OP ever so slightly, metabonomics is the study of the fingerprint of metabolic products …my paste attempt from wiki failed but you can look it up there. So as applied to wine, the compounds in the wine when it is new in life change over time and SO2 impacts those changes. And it can be studied!

Just came here to post this, and saw Tom’s link. Very interesting article, worth reading. A couple of really interesting thoughts:

“The choices made on this front, especially at the start of the process, will lead to a completely different molecular fingerprint in the wine, and to very different trajectories for the wine’s evolution in bottle,” says Gougeon. “You’re choosing either to create a pool of antioxidants in the wine or to have wines where the oxidative processes have already taken place. The earlier the sulfite additions, the more the sulfur stays in the wine.” It’s not just that a higher concentration stays in the wine but that the SO2 lingers longer because it has been more intrinsically bound into the wine. “And there’s a kind of addictive process at work,” Gougeon continues. “Once you start adding SO2, you often need to keep adding more.” Otherwise, the sulfur will dissipate, weakening the barrier against oxidation.

Comparing Allemands Sans Soufre and ‘regular’ Reynard hammers this point home pretty well (for example).

And this one:

“Wines that have had sulfite additions from the beginning have been protected from interaction with oxygen at all times,” he says, “whereas those that see no added sulfites fight oxygen and get used to it from the start. As a result, their longer-term resistance to oxygen tends to be greater.”

This seems almost counter-intuitive, and makes one wonder if higher levels of sulfur are actually promoting premox?

The idea that sulfur additions at different times would have different effects later on down the road sounds logical.

But count me skeptical on the above. I’m willing to believe if shown real evidence. Hard to know what they are thinking. Maybe that lack of sulfur early on allows the oxygen to drive all the oxidative reactions to a point where further oxygen exposure makes no difference. Doesn’t sound right to me.

The second part sounds extremely bunk. Anthropomorphism level bunk.

I believe in SO2 and I don’t think must/wines get addicted to it. I add SO2 when the fruit comes in. To put in a context people will understand more than g/l, I roughly add, depending on some variables, 75g of SO2 to a full standard fermenter that holds around 1.6-1.7 tons of fruit pre-processing. That’s about 2.75 ounces of SO2 into 3,000+ pounds of stuff. The must goes through fermentation and the SO2 is basically gone at this point. I don’t need or even want to add SO2 at this point for quite some time as I have a secondary fermentation to go through (that also generates CO2 which is also anti-oxidative) and that can take months. We also top up religiously. We add SO2 at racking for bottling and adjust slightly prior to bottling and, pH and other things dependent, end up with around 30 g/l of free SO2. I don’t bother measuring total SO2 because I know what my TSO2 additions are and that they’re very low. This anxiety over SO2 is really quite silly with the vast majority of wines discussed here and purchased by folks here. Not using SO2 does not miraculously end up with super strong anti-oxidative wines that are somehow immune to the simple basic chemical nature of oxidation.

Nicely stated, Jim . . .

I would add, for folks that want to talk about white wines and oxidation/premox, that pressing and settling white juice pre-fermentation is not the same thing as red fermentation. In the settling process of whites to, amongst other things, attempt to settle out larger potentially oxidative particles to create juice/wines with lower oxidative aspects to them we are not creating something that is powerfully anti-oxidative but something that is less prone to down the line oxidation. It’s not the same thing as being discussed in this essay.

Watching that Ramey interview is highly advised. Again.

So, no to your question.

This is one of the few discussions (the article) I’ve seen that invokes actual science and chemistry on the topic. I’m less inclined to accept “conventional wisdom” from winemakers following “standard practices” than I am to at least be open to the new and interesting directions coming out of real scientific research.

What actual science and chems, I see no real lab numbers listed. Just suppositions and observations, which may mean absolutely nothing in another grape region.

The article is summarizing a decade of work from multiple sources. It makes a point of noting these metabolomic trajectories will fundamentally vary by grape type and make-up. It’s not trying to offer up some magical new silver bullet.

Sure. No blind side by side, no numbers of any kind, just a “study”. “Multiple sources” may mean something to you, but they mean absolutely nothing to me when NOTHING is actually provided in regard to claims. Let’s see actual wine names/bottlings we can sample, side by side. Its the only “study” that actually matters and proves anything. Pictures of winemakers no one heard of, and mentions of wines not even seen/sold, prove nothing.

Show me a side by side, in a blind setup. Freshly minted, then aged X years, then aged XX years. I am tired of all the “studies” that provide nothing but names and pictures of people involved, people most have not heard of to begin with. Its not a study, just an opinion.

Hate to disagree, but I am a “numbers” person, and analysis, serious analysis when actual numbers are provided as proof. I see ZILCH in the article, and have no idea how anyone can somehow extrapolate this as gospel. Not really the first time I see similar argument, to be clear. And have no idea how anyone can take anything like this seriously. I think you and I, and some others, understand meaning of “study” in very different way. show me these wines in the article, side by side, and I may change my mind. Until then, its just a supposition. At best.

Premox. There is a study for you, in your face, so to speak. I am sure all those involved would love to be able to go back in time and change their wine making decisions. I am sure their views on SO2 have evolved, greatly, since.

It’s an article. CLEARLY, from reading it or what I summarized as “multiple sources” is the work of several research groups, not just one study. You can be curious, you can be skeptical, but misrepresenting what the articles says is intellectually dishonest. And, again, the article is talking about ongoing research. You should be able to do some leg work and find some specific results. It claims there are many.

It’s an article giving an overview of research going on. You want research results to prove to you different chemical pathways sometimes means an ester produced on one path in one fermenter may not be produced in another fermenter of the same wine?

Great! Since you still seem to be under the assumption this was a STUDY, can you tell us what were SO2 readings at time of crush, for both sets? SO2 adds during? And at bottling time, for both sets? And then readings at X years, and XX years. TIA. BLIND side by side, and lab supported. No links provided, nothing. Oh, wait! Photos! 15 minutes of fame! That’s the ticket, actual proof!

As you pointed out, CLAIMS, and nothing but. My point, exactly.

Look in the mirror before you call someone else intellectually dishonest. You obviously do not now anything about me.

No, YOU’RE the one who keeps saying it was a study. It’s an article summarizing 10 years of research in a new field. Please stop trying to win some argument, put your knee-jerk biases aside long enough to re-read the article. If you are interested in looking further into any facet of it, YOU can contact the author, do a Google search, look around places like AJEV, etc.

There is a saying about arguing with…

I’ll just let it go at that.

Yeah, sorry for trying to engage you as if you’d read the article. My mistake. Thanks for derailing an interesting discussion.