What is the role of active yeast versus cultured yeast in winemaking?

This is a somewhat brief and interesting discussion of indigenous vs. cultured yeast in winemaking.

It highlights the mutated strain that became the proprietary blend for Williams Selyem yeast which is considered to be a powerful yeast especially for fermenting Pinot Noir which Burt Williams captured during his tenure in the 1980s.

The natural yeasts are an important quality and factor of terroir expression of a certain vineyard site … so for producing individual wines true to their terroir it would be good to use (only) natural yeast …

On the other hand they are less save … they can start fermentation (too) slowly … they can develope and amplify undesired flavors … so to use cultured yeasts seems to be much safer …

I know producers of both (and also mixed) practices … and both can produce fine wines …
[shrug.gif]

It appears to me that in general, the best is a combo of both. Obviously, the style of the wine should have a big influence on which way a winemaker goes. Also, the climate has to be factored in.

From what I’ve understood, many producers who do natural wines or otherwise stick solely with indigenous yeasts, tend to use pied de cuve - that’s doing a small batch of wine (in the ballpark of a few liters) by crushing a handful of bunches and letting the indigenous yeasts start fermentation there.

When the actual harvest day comes, you have a good dose of actively fermenting indigenous yeasts you can just dump into the freshly crushed lot, not needing to worry how long it takes before the yeasts in the freshly harvest bunches kick in.

Great info. Makes sense. I’ve got to start asking some of wine making buddies what they do.

I’m not sure what you mean by a combo. Not in the same wine, I assume. My understanding is that if you put the commercial yeast in, they take over because they’re bred to act quickly.

Here is the bottom line question I continue to ask:

Is it clear by tasting or smelling a wine in bottle that that wine was fermented with ‘native’ yeast vs. cultured yeast?

How important is the yeast choice to the finished, bottled wine - especially if that wine was aged in oak?

Cheers.

I thought the native yeast added to the voodoo? newhere

Good question. I have no idea. But I do know that a high proportion of the wines I like best use native yeasts.

Well, without putting the yeast under a microscope to determine it is not a volunteered cultured yeast strain the arguement is always conjecture. The only way to know if you have a native ferment is to put it under the microscope. Period.

Everything else is wishful thinking.

I know, not a sexy viewpoint whatsoever.

Truth hits everbody, truth hits everyone.

Some wines are obviously fermented spontaneously and some wines are even more obviously fermented with cultured yeasts. However, with a majority of wines (probably ~80% or even more) I can’t tell how they are fermented.

Yet, I tend to prefer wines that are fermented with indigenous yeasts or even spontaneously. I’ve noticed this when I write tasting notes and I check up on the background data on the wines, many times the wines that I enjoy are also ones fermented with spontaneous yeasts. (And this doesn’t automatically translate to me not liking wines fermented with cultured yeasts!)

I guess yeast choice always matters, no matter where it is aged in. However, if you are now specifically referring to new oak (and its tendency to obfuscate aromas), I find excessive oak use a much bigger problem than poor yeast choice. If one is making wines aged in 100% new oak, I feel that very rarely even the fruit quality matters much, let alone yeast choices. Of course you can come up with hundreds of examples that prove the opposite, but this is just a personal preference.

For the average wine consumer, they won’t be able to smell/taste a wine and identify native vs. cultured yeast fermentation.
Assuming they even understand the technical distinction.

Bruce

Otto, I respectfully call BS to your first paragraph. And your second is probably due to your own bias in purchasing and tasting. You like producers with an ethos that includes native yeasts. You drink those more often. Therefore, you guess correctly more often that the wine you’re drinking was made with native yeasts.

What does “indigenous” or “native” yeast even mean?

So does that mean you feel that experienced tasters can differentiate? I’m not sure I agree with that.

So I should tell apart more easily which wines are made with which yeasts?

And your second is probably due to your own bias in purchasing and tasting. You like producers with an ethos that includes native yeasts. You drink those more often. Therefore, you guess correctly more often that the wine you’re drinking was made with native yeasts.

But my point was that when I don’t know anything on the wine or producer beforehand.

What does “indigenous” or “native” yeast even mean?

I guess internet is pretty full of articles on this topic.

While it is true that many times the same saccharomyces strains (ambient yeasts in the winery) finish the fermentation even when it was fermented spontaneously, much of the complexity comes from the beginning of the fermentation, when the alcohol levels are still low and many other wild strains flourish while saccharomyces is still holding back.

Larry- I think this calls for a controlled experiment- and as a winemaker you are just the guy to do it!

FWIW- I have always wondered if this is a big part of the cause of the “Rocks” character in Cayuse and Reynvaan wines- As I understand Cayuse has always been using native yeasts and I was told in the past by several winemakers in Walla Walla that they were fearful of using native yeasts as they didn’t want to end up with a stopped fermentation, or some other risk factors by not controlling the yeast.

It’s pretty easy to differentiate inexpensive Chilean wines made with cultured yeasts because they create so much varietally atypical aromatics that are a dead giveaway, just like Duboeuf’s use of that one specific Lallemand yeast strain to boost the banana aromatics in the low-end Beaujolais wines.

My guess is that the majority of the aromatic compounds you were picking up are probably due to Oak additives or Oak barrels more than they are due to any kind of yeast. Just my guess.

Nope. These are wines that are supposed to be aged in stainless steel tanks with no oak additives. And oak additives usually don’t give you that distinct blackcurrant note that tends to be identical in a great majority of Chilean inexpensive wines, be it Cabernet Sauvignon, Pinot Noir, Syrah, Carignan or Merlot.

The greatest instance here was when one producer had a mix-up with a wine lot and a batch of Syrah fermented with a yeast suited for fermenting Riesling arrived. These red wines smelled like kerosene.

And the Lallemand banana aroma is definitely not an oak note.

Don’t worry, you’re still sexy.