those unpredictable, wild and authentic, “native” yeast fermentations

Thursday, July 19, 2012

Before we get to the part where the indigenous yeasts, in colorful tribal garb, start dancing to some primeval rhythms while having juicy sex... I say BEFORE we get to that part... a word about this Wine Blogger nomination that has appeared before my jaded eyes.

Any writer, even one as ancient and jaundiced as myself, is secretly pleased to be complimented, honored in some way, hell, noticed in some way. For this I am grateful. I am, as most of you probably knew long before I did, a finalist for a Wine Blogger award. I share the nomination with my good friend Sean Sullivan and several others, in a rather odd category called One Trick Pony or something along those lines. For the record – again I say, I am truly pleased – I did not nominate myself, nor did I ask anyone to nominate me. Worse yet, I have been a less than frequent blogger of late. I am in the process of redesigning the blog, and I will resume more regular posts in the fall.

The past 12 months have been consumed with personal tasks relating to buying and selling real estate, moving primary residences, renovating and constructing three separate homes, starting up and establishing two new businesses, and trying to find time for 1) my new dog and 2) my music. So, inevitably, blogging becomes somewhat dispensable.

That said, I do appreciate the nomination, and the ongoing support of my reader.

Now, on to a new and I think more interesting topic: fermenting with native or wild or indigenous yeasts.

I haven’t seen much written about this, but it’s happening more often and it is usually the more talented winemakers who are giving it a try. In much the same way as I approach biodynamic wines, I try to focus on what I can taste in naturally-fermented wines. I have no ax to grind about whether these wines are more or less authentic, whether they are kinder, truer, cleaner, more honest, or simply give me some slender appearance of evangelistic “authority” as a certain noted east coast blogger has discovered.

No, I just want to see if wild yeasts deliver something discernible and desirable in terms of wine quality. And in my view, at least as far as the Washington wines I’ve tasted and the winemakers I’ve chatted with, they do.

I am going to do a series of posts on the topic, and I am hoping to generate a discussion that will ultimately turn into a longer article in one or more publications. For now, some questions for you winemakers out there.

1) Do you ever do wild, native, indigenous yeast fermentations?
2) What techniques do you use?
3) What grapes work best?
4) Are these truly native yeasts from the vineyard, or simply left-over from previous inoculations?
5) What are some of the risks associated with this technique?
6) What advantages/benefits do you perceive?
7) Do you agree or disagree that non-scientific tasters can find something in the scents and flavors of naturally-fermented wines that may come as a result of this approach? And if so, what would those scents and flavors be?

I will have more on this shortly, and I welcome your thoughts, anonymous or signed.

28 comments:

Nicolas said...

1) Do you ever do wild, native, indigenous yeast fermentations?
Yes - all the Rieslings at Pacific Rim are native ferments
2) What techniques do you use?
In almost all cases we do a pied de cuve (yeast starter) by bringing a sample from each block one week before harvest. Once in a while we do spontaneous fermentations.
3) What grapes work best?
Whites with low pH
4) Are these truly native yeasts from the vineyard, or simply left-over from previous inoculations?
Don't know. Since we do starters from each vineyard block we probably get a mix of things
5) What are some of the risks associated with this technique?
For the Rieslings we did not get a bad ferment in 5 years of doing this - OK may be one. For high pH wines I would think that Volatile acidity and stuck fermentations are the main risks
6) What advantages/benefits do you perceive?
It's free, it is fun and different, it might contribute to complexity
7) Do you agree or disagree that non-scientific tasters can find something in the scents and flavors of naturally-fermented wines that may come as a result of this approach? And if so, what would those scents and flavors be?

I think that if someone uses one commercial yeast all the time the wine might be a bit mono-directional. I don't think most consumer can make the difference (I am not sure I can) but I think we should care about native yeast fermentations - For me, it is a bit of the canary in the coal mine if you are seeking low input wines.

Boedecker Cellars said...

1) Do you ever do wild, native, indigenous yeast fermentations?
Yes - All of our Boedecker Cellars Pinot Noirs are native ferments. I've also experimented with Chardonnay native ferments.
2) What techniques do you use?
Spontaneous starts in each fermenter. Warm a small corner for 24 hours, then punch into the rest of the fermenter to get things going.
3) What grapes work best?
All seem to work well. Chardonnay's a little tough, but commercially inoculated Chard can be struggly, too.
4) Are these truly native yeasts from the vineyard, or simply left-over from previous inoculations?
I'm sure that the last few fermenters to start in the winery each year are heavily influenced by the "soup" of airborne yeasts. However, I definitely get different fermentation kinetics & aromatic profiles from different vineyards. That tells me that the population arriving at the winery on the fruit has a strong hand in selecting the dominant strains.
5) What are some of the risks associated with this technique?
The more exotic, non-ssaccharomyces yeasts that dominate the very start of ferments can be nutrient hogs. If you know you have a vineyard that struggles with nutrient levels, a little care and feeding (vitamins for yeast!) is prudent. Many of the non-commercial yeasts are also more sensitive to high alcohol and high heat. Not a problem for Willamette Valley Pinot Noir, but something to watch for depending on the winery style.
6) What advantages/benefits do you perceive?
More aromatic complexity. More diversity of flavor and aromatic profile.
7) Do you agree or disagree that non-scientific tasters can find something in the scents and flavors of naturally-fermented wines that may come as a result of this approach? And if so, what would those scents and flavors be?
I agree, although I think it'll be a pretty focused taster that could hit higher than 50% in a blind line up. Look for slightly higher tone aromatics and a slightly less monolithically fruity midpalate.

Micah Nasarow said...

1) Do you ever do wild, native, indigenous yeast fermentations?

Not on purpose :-) I am sure there are a few indigenous yeasts in the lot, but the amount is so low that the yeast I inoculate will overtake. When I have more room for experimentation, I am planning to start making slants of swabs from the vineyards do some trials.


2) What techniques do you use?

I stir in the must a 10% solution of potassium metabisulfite to make 50 ppm free SO2. It sits cold for a few hours and then I inoculate.

3) What grapes work best?

For indigenous yeast, I would agree with Nicolas in using low pH, high acid, and low potential alcohol varietals.

4) Are these truly native yeasts from the vineyard, or simply left-over from previous inoculations?
n/a

5) What are some of the risks associated with this technique?

Indigenous yeast most likely will have low cell counts and have a sluggish start to fermentation. Risks of stuck fermentation, off flavors, off aromas, elevated H2S. As for my small operation, I cannot risk losing wine due to funky flavors or aromas because I just let my must naturally start.
As Nicolas pointed out, they build up their yeast counts, to get a better start. As mentioned, above, I would experiment with isolating yeasts from the vineyard and build up a slurry as well before inoculation, but only in small trial bins at the moment.

6) What advantages/benefits do you perceive?

I do not agree with Nicolas that it is free. You have time, microscope, growth medium, and unfermented juice to build up the yeast counts. But it is fun to take a few cells and build them into a 2-3 gallon slurry.
One advantage is to build up a “house” flavor. One famous example is Guinness open fermentation tanks that pick up Lactic acid producing bacteria that gives the stout its smooth, round, and slightly sour flavor.

7) Do you agree or disagree that non-scientific tasters can find something in the scents and flavors of naturally-fermented wines that may come as a result of this approach? And if so, what would those scents and flavors be?

I worry that there would be sensory bias, and in my case I *would* be biased, if I was knowingly drinking wine that was naturally fermented, I would probably *think* I was picking up solventy notes or whatever. I also worry that positive aromas and flavors that add complexity could throw wine drinkers off the varietal path. For example, let’s say my merlot was naturally fermented and really developed some awesome complexity in the aroma, but Jane/Joe winedrinker says..”whoa! This does not smell like normal merlot?!?” I dunno, I am just blabbering on here.
I would think, and this is mainly from my understanding of “wild yeast” fermentation in beer/malt mediums, that the aromas produced are usually, clove/eugenol/spice, dry hay, bubblegum, source/acetic-like, diacetyl (these last two mainly due to rods and cocci that grow more rapidly than the yeast), possibly elevated levels of acetaldehyde that does not get converted to ethanol.

PaulG said...

Thanks for these detailed and thoughtful posts! I think this is a topic that has not really had much discussion. More to come!

Anonymous said...

With regard to question number 4) I think that you should have a chat with Dr. Linda Bisson at UC Davis who has done extensive work on the actual sources of "wild" yeast fermentations.
Cheers
Tex

Rory Sheehe said...

1) Do you ever do wild, native, indigenous yeast fermentation's?

Yes, depending on the vintage, fruit quality, and varietal we will do un-inoculated ferments. The idea about 'native' is obscure and misleading, although natural critters are in fact residents of grapes, it is clear (to me at least) that all ferments are finished by a domesticated strain of Sac. Cerevisiae, wither intentional or not.
2) What techniques do you use?

After cold-soak warm the must and watch the magic happen. If the aroma profile begins to go south, then we will inoculate.

3) What grapes work best?

Good, sound grapes work best. Varietals are not specific to any sort of yeast, winemakers are. However, aromatic whites will show the benefits of non-SC yeasts more clearly.

4) Are these truly native yeasts from the vineyard, or simply left-over from previous inoculations?

This is an awesome question and one that gets you thinking every harvest. The world of micro-biology is very misunderstood in my opinion, and usually fails to be defined by any scientific rationality. IMO, the distinction is inoculated or un-inoculated, but in the end it is a domesticated strain of Sacc. Cer. that finishes the wine.

5) What are some of the risks associated with this technique?

Stuck fermentations, ethyl acetate, Kloeckera, etc.

6) What advantages/benefits do you perceive?

Le sauvage, as a winemaker it is always exciting to arose something different in wine. Like above, commercial strains can lead to mono-directional wines, hence boredom.

7) Do you agree or disagree that non-scientific tasters can find something in the scents and flavors of naturally-fermented wines that may come as a result of this approach? And if so, what would those scents and flavors be?

Of course, but given blind no I dont think it would be clearly discernible whether a wine is naturally fermented. Definitely a more complex and interesting wine.

Michael Peters said...

1. Always

2. Standard protocol with nutrients, cold soak until the natural yeasts take off.

3. All varieties work. The fruit should be of high quality and free of defects. Low quality fruit will need cultured yeast to cover up the defects.

4. In different wineries with different vineyards very similar results.

5. Most see it as a risk, I see nothing but benefits for the wine. No stuck ferments!!!
6. Beautiful wines that reflect the vineyard and varietal character. Interesting wines with complexity and fewer winemaker finger prints!

7. Absolutely, wines will have more varietal character, taste fresher, less covered up by cultured yeast! Native / natural wines taste better!!!!!

Amalie Robert Estate said...

1) Do you ever do wild, native, indigenous yeast fermentations?
Yes. We rely exclusively on yeasts from our own vineyard when fermenting Pinot Meunier, Pinot Noir and Syrah. Our wines are from 100% Estate grown fruit, so we do not import yeasts from other vineyards into our winery.

2) What techniques do you use?
We use a percentage of whole clusters, perform daily punch downs and the yeast take it from there. Note that typical fruit temperature during harvest is right around 50 degrees F. in our area of the Willamette Valley.

4) Are these truly native yeasts from the vineyard, or simply left-over from previous inoculations?
These are Estate Grown yeasts and other wild things. The Estate winery has not been inoculated with commercial yeast. The only things that can ferment our wines are what come in on the fruit.

5) What are some of the risks associated with this technique?
There are more than just wild yeasts that come in with the fruit. Any number of these things can take over a fermenter and produce off flavors and aromas. And not just in the fermentation, but later down the road during barrel maturation.

6) What advantages/benefits do you perceive?
The single greatest advantage is the development of a flavor and aroma experience that uniquely represents our site. Our wines are not burdened by a commercial yeast strain that was selected to provide a certain flavor/aroma character at the expense of all other flavor and aroma compounds. Also, the fermentation curve (the time/temperature in fermenter to dryness) is significantly different. You can read more detail here: http://www.amalierobert.com/2011_Spring_Cellar_Report.htm

7) Do you agree or disagree that non-scientific tasters can find something in the scents and flavors of naturally-fermented wines that may come as a result of this approach? And if so, what would those scents and flavors be?
Perhaps the inverse is true here. What flavors and aromas are not present (from a monoculture commercial yeast strain) that would mask the true expression of the wine? We look for more nuance and several components that make up the bouquet. That being said, you can have virtually any flavor and aroma profile you desire by selecting a commercial yeast strain such as one of these: http://www.lallemandwine.us/products/yeast_strains.php

Do you ever wonder why some large production wines taste the same year in and year out?

Stacy Vogel said...

1) Do you ever do wild, native, indigenous yeast fermentations?

Our Pinot Noir, Syrah and about half of our Chardonnay here at Miner Family is allowed to undergo a wild fermentation

2) What techniques do you use?

No specific techniques related to the native fermentation, but the most important part of a wild ferment is to keep a very careful eye on it, especially the first few days before the fermentation takes off -- tasting and smelling each tank/bin/barrel several times a day

3) What grapes work best?

We like it on these three varieties because of the slight "funk" that a wild fermentation can impart -- goes well in Pinot and Syrah especially

4) Are these truly native yeasts from the vineyard, or simply left-over from previous inoculations?

Linda Bisson will tell you that it is pretty well established that every winery has a "house" yeast that resides in the winery, and that yeast will be the one that finishes the fermentation. However, the yeast and bacteria that come in on the grapes do some action at the very beginning, and that is the "funk" or "complexity" that people often associate with native ferments

5) What are some of the risks associated with this technique?

Those beginning yeast and bacteria, especially, can lead to big VA and/or ethyl acetate (nail polish remover) problems, which is why sensory monitoring the first few days is so important

6) What advantages/benefits do you perceive?

Again, it can contribute a certain complexity to these lots

7) Do you agree or disagree that non-scientific tasters can find something in the scents and flavors of naturally-fermented wines that may come as a result of this approach? And if so, what would those scents and flavors be?

Sure, some people naturally have great palates and could pick out differences. It's all about preference -- I have done yeast trials every year and we don't always prefer the native fermentation. We're not tied to an ideology about what constitutes a better wine; if a "monoculture" yeast strain means that my wine is "lacking" the aroma of ethyl acetate, I am OK with that

Anonymous said...

I'm a small winery in a warm area growing warm climate varietals. If uninoculated fermentations can be done with any degree of success around here then this winery, or one similar, is probably the place to do it. That being said, uninoculated fermentations can have several outcomes, only one of which is good. Frankly, my dear, they scare the hell out of me.

I prefer the reliability, convenience and predictability of ferments conducted with commercially prepared yeasts of a known strain with repeatable kinetics to do my work. I like making wine that I can sell, I like not having anybody ask "what is that smell?", and I like being able to sleep nights not having to worry about a stuck ferment.

I use yeasts that were isolated in the same region that the grapes they are fermenting originate. For instance T73 (Rioja isolate) for Tempranillo, D21 (Rhone isolate) for Syrah, etc.

While studying at Davis I recall seeing a study on yeasts that indicated that the various strains gave different flavor profiles to a wine for the first year only and that after that it pretty much made no difference what strain of yeast did the ferment. However, if you go uninoculated and the wine develops significant defects such as VA or sulfur problems they can be with you forever.

My grapes come into the winery with no less than 100 or so native microflora on them and in the microbial miasma that is a beginning ferment it's a dog eat dog, dog doesn't return dog's phone call, dog steals dog's wife world and I for one want the good dog to come out on top. The Linda Bisson study that somebody else referenced suggests that most uninoculated fermentations are the work of yeasts previously brought in that remain resident in spore form waiting for a tasty meal of grape juice. It's a bit like the hired gun putting on the Sheriff's badge in an old Randolph Scott movie. The Sheriff's job is to overpower the bad guys and maintain order. If that is happening in your winery you are truly fortunate.

A number of years ago Joel Peterson at Ravenswood did a native yeast ferment on some Chardonnay from Sangiacomo vineyard that was my first (to my knowledge) experience with a new world uninoculated fermentation. I charitably described it to a colleague as eccentric. It had an aroma I would later come to associate with schizosacchramyces which suggests that it was a true wild yeast ferment.

I use commercial yeasts, I have little to no interest in trying an uninoculated ferment, and I make no apologies for it.

Jim Johnson
Alamosa Wine Cellars
Bend, Texas

PaulG said...

These are wonderful, thoughtful comments. Thank you one and all. Although most posters here are in the pro-wild camp, I appreciate Jim's honest and detailed explanation as to why he wants to stay with the tried and true. I think there is certainly room for all, and apparently, the jury is still out on the plusses and minuses of native ferments. I can tell you that this past spring I received a young wine - a chardonnay - that was quite bizarre and seemed waay out of line with the winery's previous efforts. I re-tasted it twice more, from different bottles, at intervals of 2 and 4 months. In this instance, the wine did come around, but remained unusual. I don't think it would do well in a wine judging with a group of similarly-priced chardonnays. It would certainly be the odd man out.

Anonymous said...

I'm not a winemaker, and although I drink my share of wine, I'm largely unaware of whether I'm drinking wine with wild yeast. The one wine that I do know uses wild yeast is also one of my favorite white wines. It's a viognier from an Israeli winery called Dalton named, unsurprisingly, "Wild Yeast Viognier." It's a hard but not impossible bottle to track down in the US, and if you come across it, it is worth trying.

Kim said...

1) Do you ever do wild, native, indigenous yeast fermentations?
We conducted a small trial last year.

2) What techniques do you use?
The grapes were harvested, sorted, destemmed, and then allowed to spontaneously ferment. When the cap formed, nutrients were added. Then, the fermentations were punched down once or twice daily until dry.

3) What grapes work best?
N/A

4) Are these truly native yeasts from the vineyard, or simply left-over from previous inoculations?
One of our goals with this trial was to identify our native strain or strains so we could manage the fermentation more effectively. The DNA in the native ferments was analyzed and matched against known strains of yeast used in our cellar since 2005. We were unable to identify the dominant strain of yeast using this method. Based on this experiment, I'd conclude that the yeast came from the vineyard.

5) What are some of the risks associated with this technique?
In our experiment, two of the three native ferments would not have made commercially viable wines due to overwhelming ethyl acetate. Thus, EA and VA would be my biggest concern. Yeast stress is another, but that wasn't a factor in our trial.

6) What advantages/benefits do you perceive?
Greater complexity in the finished wine, reduced harvest costs.

7) Do you agree or disagree that non-scientific tasters can find something in the scents and flavors of naturally-fermented wines that may come as a result of this approach? And if so, what would those scents and flavors be?
Disagree. Although problematic fermentations result in similar characteristics, such defects can be found in wines produced with commercial yeasts as well. In the case of a healthy native fermentation, I have yet to observe any particular set of aromas or flavors that would identify the wine as such.
Our trials with native and commercial yeasts indicate that site, vine age, clone, vineyard management decisions, and a healthy fermentation are far more important than yeast selection in determining a wine’s personality. While yeast selection, including the decision to utilize native yeast is a part of that equation, it is one of many variables.

Philip Coates (21 Cellars) said...

1) Do you ever do wild, native, indigenous yeast fermentations?
At 21 Cellars in Tacoma, WA, we use native yeast for 100% of our production.

2) What techniques do you use?
We start with a 5-7 day whole berry cold soak, then we let the temp rise to ambient, when it hits the mid 50's fermentation starts naturally. For our barrel fermented Cabs we hand load each barrel with about 400 pounds of hand-destemmed fruit (takes about 4 hours per barrel) and sufficient dry ice to maintain the cold soak. Barrel fermentations take about 60 days although we have had Cab on the skins for up to 13 months.

3) What grapes work best?
All work well, though we have found our Tempranillo to be a particularly hot fermenter and our Red Mountain Cab to be particularly cool. For whites our Sauv Blanc and Semillon work quite well.

4) Are these truly native yeasts from the vineyard, or simply left-over from previous inoculations?
Good question. We have found incredible consistency in fermentation characteristics from each vineyard from year to year, all vineyards being quite different. So, I would say the vast majority is resident vineyard yeast.

5) What are some of the risks associated with this technique?
Stuck fermentation or off flavors. We have not experienced this, but I have heard this can occur in about 10% of native fermentations.

6) What advantages/benefits do you perceive?
Cost (although this is assuming no production loss due to off-fermentations), differentiation from the masses, unique flavors like a hazelnut finish to our 2009 Malbec

7) Do you agree or disagree that non-scientific tasters can find something in the scents and flavors of naturally-fermented wines that may come as a result of this approach? And if so, what would those scents and flavors be?
Agree, we have plenty of non-scientific tasters each weekend in our tasting room who thank us for taking the extra risk in producing our wines. In addition to other varietals, we source 3 Cabs from top vineyards, with lab yeast all could be engineered to taste similar, with native yeast all are distinctive, which is important when releasing vineyard designated wines; you are getting a more true expression of the vineyard.

Anonymous said...

At one point in my life I was seriously thinking of basing my master’s degree in on this very subject. I read a lot of scientific articles about this a proposed a few experiments to my professors to answer this very question. At the end of the day, I just wanted to make wine and was burned out on school.
Now as a winemaker, I have come to the conclusion this is just a matter of, “to each his/her own”. FACT: Great wines can be made with both “natural/ native yeast” as well as the not as sexy sounding cultivated-“store bought yeast”,( caveat) as long as the winemaker know what the hell they are doing. It is true that anything that has the word natural must be better right?
Winemakers no matter the choice of yeast, we are trying to do the same thing, get the wine dry!! ( with the exception to some white wines and market accepted slightly sweet red wine) and stable without significant defects. Some if these defects may add complexity but that’s a whole other subject.
What can be gained or loss due to these natural ferments, I think, can be made up with vineyard section, pick date, barrel selection, winemaker blending, cap management, pressing timing and a host of other things.
As far as I know there has yet to be a “sugar fungus” yeast cell isolated from a vineyard, unless the said winery is dumping pressed grapes back into the vineyard. At the same time it that bugs that is finishing the fermentation to dryness. Even in inoculate musts, it’s been shown that there are as many as 15 different yeast strains it the must and presuming living and cutting the sugars off aroma pre-cursors.
Overall, to me it’s a matter of marketing and telling a story. If the wines are great and made with that one technique, hey that’s great, more power to you. I just ask that if a winemaker chooses another path that wine dorks and critics don’t say that said winemaker is being uncreative or unnatural. Let the wines speak for themselves.

David Larsen said...

Paul,

Excellent questions because, as a winemaker, I am learning a lot from the other comments.

We began experimenting with native yeast fermentations a few years ago.

To minimize the alleged risks, we have only done native yeast fermentations with vineyards that fermented readily using designer yeast.

As with our innoculated ferments, we add 50 ppm of SO2 at crush then simply wait for the native yeast to do their thing. There is a lag time of just a few days. If the temp of the must is a bit cool, we spray a light mist of SO2 on top daily to prevent ethyl acetate.

I don't know the source of the native yeast but there is a definite differnce in the character of the wines. They are less fruit-forward but have more complex flavors.

Contrary to what I've read on this subject, the wines seems to ferment to dryness faster with no additional VA. The wines seem to also be more harmonious and balanced.

So far, I prefer the wines made using native yeast.

Erika Szymanski said...

I wish that the "Anonymous" who nearly did a Masters on this topic had left an identifier; this was among my dream projects for a PhD diss, too. Just a note that Saccharomyces has been isolated from the surface of wine grapes and rachi (pending research at my institution and published elsewhere, I believe), though it is grossly outnumbered by other yeast species.

What I find most fascinating about this topic is how little people agree. I doubt that additional research will do much to change that, either; individual winemakers and winedrinkers will continue to maintain that they can or can't taste the difference no matter what the Davis crew (or AWRI, or WSU, or Cornell) says. So, WHY? Why is this such a polarizing topic? Why, when very good (and very bad) wine can indeed be made via either method, do people feel so very strongly about it?

I look forward to the continuation of this conversation.

PaulG said...

Erika, I agree. This seems like a topic that needs much more discussion. I am heading out on the road for the next 10 days and will have limited access to this blog, unfortunately. But let's keep the ideas flowing and I will tabulate them as soon as possible and we'll do more.

Man About Wine said...

Hey, what's the idea of doing a blog post that is useful?? Not ranteyed? Actually trying to open to the public some legit info on the wines they like?

I don't make wine,I sell, but I remember the first time I tasted thru a lineup of David Ramey wines. Each tasted different, even after going back & forth for a while. I admired that. Then, I find that yeast is his major at UC Davis and his fascination etc. So no surpise then that I continue to like the character in his wines. Not cookie cutter.

Anonymous said...

I have graduate level academic experience with this topic. Let's put a few things straight to frame this discussion:

1. "Native" is a misapplied term. What these winemakers really mean is "uninoculated." They have no idea whether their fermentations are controlled by a resident population of Saccharomyces that originally came from a bag or authentic "native" yeast.

2.Regardless of which side of the fence you're on, practically every winemaker (that doesn't have a "native" axe to grind) believes that yeast selection has absolutely no effect on aged red wines.

3. As a winemaker, and as one that has experimented with cultured strains of "wild" yeast, I can tell you that at their most prominent (right after fermentation) there is very little differences in aroma and flavor character in wine.

4. What most winemakers depict as differences in aromas and flavors in finished wines are really differences in H2S, a yeast-produced off-aroma. Get rid of H2S, as is good winemaking practice anyway, and you eliminate perceived differences in yeast selection.

5. This is a perfect example of "holier than thou" winemaking. Do you practice organic / biodynamic / "sustainable" grape growing and winemaking? No? The horror!

Art said...

From the Unti Vineyards (CA) website . . .

"We strive to pick our grapes at that ephemeral moment when they have the most to give. We try to steer the fermentation in a direction we believe reflects the inherent grape characteristics, the soil they are grown in and the weather of a particular year. To achieve that, the winemaking is shed of as many external influences as possible, i.e. commercial yeasts, acidity correction or fining agents. While chemical analysis of must and wine can be helpful, it is ultimately our senses and intuition that enlighten our choices.

"Natural or hands-off winemaking doesn’t mean thoughtless winemaking. We stay away from technological or chemical tools but we do influence the fermentation dynamics, and the resulting extraction of grape compounds into the wine, through physical processes like temperature control, intensity of crushing, frequency of punch-downs and pump-overs, length of maceration time, etc..

"In our quest for truer-to-their-roots wines we adopted the antique whole cluster fermentation method that is still widely used in the Rhone: meaning grapes are harvested very cold early in the morning, sorted and placed in shallow wood or stainless steel tanks where they are then stomped by foot. The fermentation starts naturally after 5 days of soaking thanks to indigenous yeasts. We started experimenting with whole cluster fermentation on Syrah in 2005 and have now extended the technique to Mourvedre and Grenache. The presence of stems and a higher proportion of whole berries in the fermenter seems to widen the aromatic profile of the wines (more peppery and floral notes) as well as providing them with a focused structure."

Can one conclude that shedding "external influences" in winemaking is a positive? As a consumer, I think so. Should natural fermentation dynamics be influenced by "physical processes" as described? Sounds good to me. I admit, though, that knowing about and appreciating it may be more important than actually tasting dramatic differences. Kind of like religion.

Anonymous said...

Just for fun:
Why I do not do native fermentations: An analogy…
It’s offend said that there are 1,000 ways to cook a chicken. How you do like your chicken cooked? Roasted? Deep Fried? Smoked in oak chips? There are so many different styles of chicken, some are great and some suck, but when chicken is done perfect we all know it.
Like most other chefs I get my chicken fresh off the farm, I have great relationships with my chicken growers and make sure my chicken is nurtured and cared for as it is being raised. Pretty much like every chef, I carefully check on my chicken every few days as it’s about to be ready to be processed.

When it’s time to slaughter that chicken, I get it back to the kitchen as fast as possible, I clean the whole boy off ( 35 ppm so2) and I get it ready to be cooked as soon as possible ( I add 1/3 of my yeast inoculation within hours of being crushed, the other 2/3rd after lag phase). For me personally, I don’t add any seasoning (oak chips(pepper), tartaric acid (salt), or tannins( liquid smoke). I want my patrons to taste the freshness of this chicken that has been so diligently raised by my growers (and that I pay good money for).
With that said, I don’t want my super fresh chicken sitting on the counter top for days at room temperature building up potentially harmful bacteria( and losing its natural color) Sure if I cook the hell out of the chicken, most of those bacteria will be killed off and my patrons will not get sick. But I like to get that super fresh chicken in the oven and cooking (fermenting) as fast as possible. Sure I have a normal name brand oven, it’s a Viking and I paid some good money for it. Other chefs tell me that there oven is off brand and they really don’t know who made it. Then they tell me it cooks in a way that adds complexity to their chicken, it starts off slow but then builds in temperature. I just say to myself, they are full of shit, we are all cooking chicken the same way ( with saccharomyces) you let your super fresh chicken sit out in the sun for three days and I get mine cooking right away. Who is the best chef? I don’t know. But that’s just my way to think that I am being true to my chicken farmers, reflecting their land and the way they grew there chickens. We may both end up with good tasting chicken, but at the end of the day it’s up to the food critics and patrons to tell us if they like the way we cook and stay in this crazy super hard “perfect” chicken cooking business.

Anonymous said...

At Array Cellars, we experiment extensively with different yeasts in our chardonnay, the only grape we use. We combine that with using many different new barrels, all Burgundian. It's fascinating to taste through the array of combinations and note all the different flavors that result. Native yeasts impart dramatically different flavors to chardonnay than inoculated yeasts. One need not be a scientific taster to detect it. When you vary the barrel, there seems to be an interaction between the barrel and yeast, and identifying the flavor profile of each becomes more unpredictable. But we've found that in the vast majority of samplings that the native yeasts impart more interesting and pleasing flavors.

What are those flavors? I consistently detect a spice component in the finish that is missing in the inoculated yeasts. And remarkably the fruit flavors often (but not always) seem more intense. While this seems a little puzzling, it has been noted consistently. There have been comments noted in this blog about off- flavors migrating in with the yeast, but this has fortunately not yet been our experience. In short, I love using native yeasts in making chardonnay. The delicacy of this grape allows the enhanced flavors of the native yeasts to shine through. The power of red wine grapes and the weight of oak used in making them would, I expect, make it harder for the taster to identify the impact. But for chardonnay, and I expect for other grapes with delicate flavors like riesling, the native flavors enhance the wine.

Kathy said...

This is fascinating, Paul. I am not a winemaker. Here are two thoughts about wild yeast from winemakers I know.
1. Bordeaux. Biodynamic vineyard (cab sauv and merlot). Small production, not a lot of UCD-type knowledge. After five terrific vintages with wild yeast, last three had problems. Most likely associated with something floating in the grange. '11 vintage ended up as vinegar.
2. Tejo, Portugal. Very good winemaker. Does not use wild yeast because his tests determined that the wild yeast was not compatible with the native white grape and he is one of the best for this variety in Portugal (can't remember name, ask Roger). The vineyards have multiple varieties, as is often the case in Portugal.
My questions:
1. I didn't see cab sauv amongst the grapes in comments. Are there "good" and "bad" wild marriages? (I should probably trademark that).
2. Is there a sea/ocean impact on wild yeasts for coastal vineyards?
3. Does one variety impact another (thinking regions with multiple red and white varieties) - for better or worse?
4. Is there a difference between classic varieties/classic clones and native varieties (Portugal, Italy, SW France for example) and how the wine "takes to" the wild/native yeast?
Sounds like a petition for a university grant for somebody.

Marie-Eve Gilla said...

I find the topic fascinating and could discuss it lengthily, having done native fermentation in Burgundy and some parts of the new world as well as added yeast to many other ferments in my 20 plus years of winemaking. Whether the goal is to achieve a clean, fresh and fruity wine using commercial yeasts in a controlled environment or a more complex and sometimes altered wine in more "wild" conditions (which is actually a more difficult fermentation to complete), I think all styles should be allowed as long as the winemakers understand and can adapt the grape conditions and winemaking protocol to their goals.
My only worry is that the recurrent and trendy pitch for native yeasts fermentation will corral us (winemakers) to use that route in order to satisfy the latest trend instead of focusing on producing the best wine by adapting winemaking protocol to the growing conditions of the vintage and the site.

Anonymous said...

Paul:

I recently returned from a trip to Provence where I took a day-long guided (See Olivier Hickman's website) tour through Gigondas, Vacqueyras, and Chateauneuf-du-Pape. We visited the great (admired Beaucastel's rocky soils) and very good indeed (keep an eye out for wines of Sablet, a tiny village on the move).

Now, I admit I came to Provence with an inadequate education. I took a three unit wine appreciation course as an undergraduate at UC Davis called Vit 3 (go Aggies!) 25 years ago and since then I have made a few unsuccesful attempts at homewinemaking. In other words, I came to the Rhone with an unquestioned belief that a fussy, science-minded winemaker was a good winemaker. The winegrowers of the Rhone upset many of my settled beliefs:

1. The great domaines do not train their vines. The grapes at Beaucastel grew on irregularly shaped and and spaced bushes.
2. They do not irrigate. The best vineyards are in the worst soils (if you can call a bed of rocks soil) where the vines have to grow deep for a steady supply of water.
3. They do not use laboratory yeast (returning the subject of your blog). They use whatever yeast the Mistral brings their way.
4. They age the wines in concrete (yes, concrete) vats. Only the overly tannic wines take oak. If they must use oak they prefer used oak (very used oak).
5. And, here's the biggie: The winegrowers of the Southern Rhone don't "make" wine. In fact, you would insult a Rhone winegrower by referring to him/her as a "winemaker." They instead speak in terms of trying not to get in the way of what happened in the vineyard. Terroir (now you know I just returned from France).

Where does this leave us in California, with our cult winemakers and their endless tinkering in the cellar? Are we making wines or are we making celebrity winemakers to pair with our celebrity chefs? "We had a lovely evening in Berkeley drinking Jean Phillips' wine and eating Alice Waters' food."

Courtney (still off-the-grid in East Sacramento)

Plymale said...

Great discussion!!! Thanks!

suamw said...

http://www.centralcoastwinereport.com/winesooth/2008/10/12/yeasts-gone-wild-part-1/

http://www.centralcoastwinereport.com/winesooth/2008/10/15/yeasts-gone-wild-part-2/

http://www.centralcoastwinereport.com/winesooth/2008/10/17/yeasts-gone-wild-part-3/

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