Getting the yeast right

originally posted by Jeff Grossman:
originally posted by Aaron:
But it's still cheating.
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"Cheating" is a funny word and I think you're being too arch.

I don't think anyone here is arguing that the wines should make themselves. I'm concerned about how many interventions, how many additions (and of what... sugar is pretty ordinary, God only knows exactly what's in Ferms-A-Lot), etc.
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Well, I didn't mean to be arch, but I did mean to point out that adding sugar to juice is no more natural than, say, acidulation, but it seems to me we look askance at the latter practice and for no better reason than we prefer the style of wines that are Chaptalized but not those that are acidulated. It's hypocritical, and I'm guilty of it too, but I don't think it's an unfair criticism. And you shouldn't take that as a defense of Fermichamp, Mega-Purple, or any of the lab-synthesized shit that are anathema to any Disorderly.
 
Let me try again: I do not agree with you that there should be no additions. It is perfectly reasonable to say that some additions are good and some additions are bad. So, I do not see hypocrisy because I do not hold the all or nothing position.

Said another way...

My great-great-grandmother would recognize sugar. Go ahead and add it.

My great-great-grandmother would not recognize ammonia salts (DAP), free amino acids (organic nitrogen derived from inactivated yeast), sterols, unsaturated fatty acids, key nutrients (magnesium sulfate, thiamin, folic acid, niacin, biotin, calcium pan­tothenate), etc. Do not add it.
 
I personally am aggravated by the use of oak, clay, and other traditional containment materials in which wine develops, since they alter taste and texture in various ways.

Ideally grapes would ferment themselves in a vacuum, but I suspect the brutal cold and lack of gases would interfere with the process.
 
His take on yeast selection reminds me of the Stonecutter's episode of the Simpson's. "They looked deep within my soul and assigned me a number based on the order in which I joined."

Sounds like terroir/yeast matching, no?

Cheers,

Kevin
 
originally posted by SFJoe:
originally posted by Jonathan Loesberg:
It's my understanding that naturally occurring yeast tends to die naturally, thus ending fermentation regardless of the sugar content of the wine, at somewhere around 14% alcohol.
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I think that is old information.

More later.
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Because it was never true or because, as I said, yeast has evolved?
 
originally posted by Jonathan Loesberg:
Because it was never true or because, as I said, yeast has evolved?
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I think it was never true. Sure, you'll have more stuck fermentations the higher in brix you start, OTBE. But people did ferment warm vintages of Chateauneuf with native yeasts in the old days, and still do, AFAIK.

I recall a report about Turley Cellars having isolated a yeast that fermented to 17.5 or 18%, which does seem totally heroic. But I believe it was an isolate from a spontaneous fermentation that had gone that far, and they just reproduced the last microbe left standing.
 
originally posted by Jeff Grossman:
My great-great-grandmother would recognize sugar. Go ahead and add it.

My great-great-grandmother would not recognize ammonia salts (DAP), free amino acids (organic nitrogen derived from inactivated yeast), sterols, unsaturated fatty acids, key nutrients (magnesium sulfate, thiamin, folic acid, niacin, biotin, calcium pan­tothenate), etc. Do not add it.
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'Pretty to think so.
Best, Jim
 
I grow six grape varieties. Of these, syrah and garnacha are regularly between 14.5% and 15% alc, bobal and monastrell between 14% and 14.5%. When we started 10 years ago, my winemaker and friend Rafa Orozco was very concerned that we couldn't get them dry without cultured yeasts, but when I did convince him to stop using any of them we discovered quite the contrary: the native yeasts produced a roaring fermentation which we always have a hard time toning down to keep it gentle and slow, which we do by cooling the small (four ton) open fermenting vats as well as we can. Our wines are always around the 2 gr level in residual sugar and I haven't heard anyone describe them as 'sweet'. So, yes, you don't need the selected yeasts to finish your wines if your grapes are right.
 
originally posted by Jeff Grossman:
Let me try again: I do not agree with you that there should be no additions. It is perfectly reasonable to say that some additions are good and some additions are bad. So, I do not see hypocrisy because I do not hold the all or nothing position.
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From the perspective of expressing terroir I'd think that some additions are bad, and others are less bad. The only possible exception to this rule that I could think of would be SO2 in the later stages of a wine's development pre-bottling. I guess the absorption of ambient gasses (O2) and the effect of ambient temperatures in the cellar might also fall into a grey area, but beyond that I don't see much "good".

When it comes to taste, the "some good, some bad" metric works over a rather short time frame. But thinking long term, I believe, puts us on the same footing as that mentioned above... it becomes hard to qualify any addition as "good", since the additions become crutches that prevent the fundamental re-think necessary to achieve the very best from any given piece of land.
[Those trying to grow grands vins under glass up in Reykjavik are excluded from the discussion.]

Cheers,
 
For red wine fermentation I don't see much of a problem in getting the wine to go dry with ambient yeasts if the must is anywhere up to low 15s as potential alcohol.
White wines OTH can be difficult. One of the better justifications for going orange...
 
originally posted by VS:
I grow six grape varieties. Of these, syrah and garnacha are regularly between 14.5% and 15% alc, bobal and monastrell between 14% and 14.5%. When we started 10 years ago, my winemaker and friend Rafa Orozco was very concerned that we couldn't get them dry without cultured yeasts, but when I did convince him to stop using any of them we discovered quite the contrary: the native yeasts produced a roaring fermentation which we always have a hard time toning down to keep it gentle and slow, which we do by cooling the small (four ton) open fermenting vats as well as we can. Our wines are always around the 2 gr level in residual sugar and I haven't heard anyone describe them as 'sweet'. So, yes, you don't need the selected yeasts to finish your wines if your grapes are right.
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It seems like the process of natural selection would bias yeast populations over time towards those with the highest alcohol tolerance - these would be the 'last standing' (in Joe's happy phrase) and therefore, you'd think, the most prolific propagators in the local environment. But I own to not knowing the details of yeast reproduction (apart from cell division in the medium).
 
originally posted by Ian Fitzsimmons:

It seems like the process of natural selection would bias yeast populations over time towards those with the highest alcohol tolerance - these would be the 'last standing' (in Joe's happy phrase) and therefore, you'd think, the most prolific propagators in the local environment. But I own to not knowing the details of yeast reproduction (apart from cell division in the medium).
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Studies have shown that it tain't so simple, though, Ian. During the course of fermentation, several different yeasts may come to prominence only to later fade. As a for instance, one yeast may be particularly well suited to the high osmotic pressure conditions found at the beginning of fermentation but peter out as alcohol levels grow only to be replaced by another, more alcohol tolerant, strain.

Mark Lipton
 
And so, the last one left standing in one boozy fermentation may face many difficulties colonizing the next batch a year later. The fermentation vessels, hoses, pumps, etc., etc. will be cleaned and sterilized, and there will be a long wait until the next vintage. How good are they at being dormant and reviving?

The alcohol-tolerant and sugar-shunning yeast will be at a disadvantage early in any fermentation, when there will be a lot of sugar and not much alcohol.

Natural selection will continue to operate, of course, but it will operate in a series of shifting environments that will favor many different traits. It is not a simple matter of alcohol tolerance that the winery will select for.

That is, until late in the next vintage when depending on weather and etc., there might be another high alcohol fermentation to colonize, though there will again be a different selection on the ability to move from

Without human intervention, can our uber-yeast colonize that fermentation and appear in sufficient numbers at the right moment to be the "it-yeast"? To carry it forward and be the dominant strain?

If you were just passing winery fermentations batch to batch it would be one thing, but you wait a vintage and bring in a totally different high sugar, low alcohol must filled with a diverse flora (if your viticultural practices allowed such), you face a different sitch.

The literature will be definitive quite soon with the steep fall in sequencing prices, but I bet it backs up the limited data to date that says that much of the diversity comes in with the grapes if you haven't sprayed so much & etc. to have killed it all.

Time for bed, more to follow.
 
I'll happily cede to Victor and Joe on the inaccuracy of what I said about yeasts. I don't think CdP from before 1998 though is evidence of that. Alcohol levels in CdP prior to then were typically about half to 1 percent lower than they are now, even for very traditional winemakers.
 
Thanks. Did some light reading and imagine that sporulation give the 'it' strain of the moment pretty good chances of dormant survival, once its preferred conditions have passed, until the next year. The more committed a winery is to controlling yeasts, naturally, the more carefully it will control the environment, and the harder it will be for the dormant strains to hang around.

I didn't know that yeast reproduce in a rich medium by budding rather than division.

Is it general knowledge whether brettanomyces and acetic acid bacteria do better or worse in an environment crowded with natural yeast?
 
Jonathan, CDP is an example of a place where in some spots abuse of the vineyards with treatments stripped the soils of nutrients and robbed natural yeast colonies from the stands and from cellars, but also an example of a place where big wines did in fact ferment out well over 14% and indeed well over 15% in hot years without inoculations. Yes, average alcohol levels have jumped for many reasons here, as in other places, but CDP most certainly produced big and very big wines before people discovered worse better living through chemistry.

In simple terms, there no set alcohol limit for alcohol conversion with natural yeast, because performance will depend on many conditions. Local yeast strains available to handle different stages of fermentation is the most obvious one, and that will depend on the condition of the vineyard and the transport environment and the cellar. Vineyards need in somecases to be reconditioned for some years to recover the complete balance and set of nutrients to support a full and fully functioning population of yeasts. Another factor is time. Growers returning to noninoculation have a terror of delays in fermentation, and they may need to get fermentation done before a certain date for financial reasons. But, especially in a warm climate with lots of sugar to turn over, fermentations may stick and need time and patience to get restarted.

But a healthy and diverse population working in reasonable conditions can and did ferment out big-year CDP long before anyone came along with cans of killer yeast.

That said, I would rather drink with from a good grower who thoughtfull experiments with and uses yeasts or whatever than the wine of an imbecile doing a cuvée whatever because it's now fashionable or because he was browbeaten into doing it.

And not all treatments are on all fours.

But I'm losing power. Bye.
 
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