Wild/natural yeast fermentation - no more commercial yeast! ??

[sjjan]

So, last year I made wine using commercial yeast. This coming September/October I am about to receive about 2400 kg of grapes and this time I would like to do the fermentation with natural yeast fermentation, but am feeling uncertain on how that is supposed to work. My winemaker friends (winemakers from Stellenbosch, South Africa as well as several winemakers from the Alsace region in France) all swear not to ferment anymore with commercial yeast. No more destemming (whole grape pressing) and no commercial yeast is the trend over there in the Alsace and with those wineries in South Africa. So, is there anyone on the WMT forum that has experience with it and can point me in the right direction? Thanks. SJ

 

[Cynewulf]

There are a few of us who do/have done it here. I did it for the first time last year and documented it here: Adventures in Wild Fermentation. I’m in the middle of my second season of spontaneous ferment and everything is going well. I also follow a YouTube channel that features interviews with French winemakers that exclusively make ‘vin nature’ and have learned a lot from those folks. Do you have any specific questions? Most of the processes are the same: make sure everything is super clean, press or crush your grapes, and you should see some fermentation activity after two days or so. One decision will be whether to add SO2 and if so how much. Some people add none to encourage the greatest amount of biological diversity, others small amounts at crush and/or in emergencies; it can depend on your juice chemistry and the condition of your grapes.

 

[NorCal]

...and our "commercial" yeast is often other people's "native" yeast.

D254: Isolated from Costieres de Nimes area, Rhone Valley.
D80: isolated yeast found in the Rhône valley.
1118: A Strain selected in the Champagne region

I think what becomes "native" in most wineries is the "commercial" Saccharomyces yeast that was used in previous ferments in the winery.

Ken

 

[sjjan]

Thanks for a first hint, some links and a doubt about the true nature of “natural yeast”. I will study that first, then get back with questions. Ok? I am in the middle of some travel for work so have to read up in spare time.

 

[cmason1957]

I have done a natural ferment a few times. and I have a friend who owns a winery out near Hermann, MO who only does natural ferments. I don't think there are any big things you need to do. I have added a smaller than normal dosage of Kmeta at the start, to combat spoilage bacteria, then let it go. In my experience, it just took off and things went fine. I did add nutrients, since I know most of the grapes in MO need extra. not a big deal really and I often chuckle, but just scroll on by those who say natural yeast won't get beyond 8 or 10% abv, from my experience they got to 14 quite fine.

 

[toadie]

I don't have much to add but a similar sounding yeast situation is the cool ships beings used to open air inoculate lambic beer in Belgium.

 

[Cynewulf]

I think what becomes "native" in most wineries is the "commercial" Saccharomyces yeast that was used in previous ferments in the winery.

I read an article on that a few years ago and was convinced but now I’m not so sure. I hadn’t used cultivated yeast before making wine for the first time last year and had no problem with the grapes from my vineyard spontaneously fermenting to dry. Based on what I’d read I was a little worried I’d have issues because I hadn’t inoculated before but it ended up not being a problem. I think folks doing spontaneous ferments may also be more interested in the non-Saccharomyces yeast populations that are active early in the ferment before one strain or another of Saccharomyces grows large enough to take over and finish things off: the Pichias, Torulesporas, Hanseniasporas, etc.

I do find the theory in this article interesting, it made me think of the pesky wasps in my vineyard a little differently: The Role of the Social Wasp in Yeast Ecology: Thank Your Local Wasp for the Complexity of Your Wine

 

[Rembee]

Thanks @Cynewulf for the article link post. That was a very interesting read!

 

[Rembee]

I find the whole concept of spontaneous fermentation very interesting. Although I have not performed a wild yeast fermentation with grapes, I have just a few months ago performed a spontaneous fermentation with my home grown blueberries. The link to that thread can be found here.
https://www.winemakingtalk.com/threads/blueberry-wine-with-spontaneous-fermentation.73866/I've had great success with this spontaneous fermentation and it did ferment to dry, SG of .994. It started at a SG of 1.090. It is presently sitting in bulk, aging and clearing up very nicely.
The aroma is very fruit forward with a very nice mouth feel. I am very pleased with its outcome so far.
This is a interesting thread also and I will be following it!

 

[David Violante]

I read an article on that a few years ago and was convinced but now I’m not so sure. I hadn’t used cultivated yeast before making wine for the first time last year and had no problem with the grapes from my vineyard spontaneously fermenting to dry. Based on what I’d read I was a little worried I’d have issues because I hadn’t inoculated before but it ended up not being a problem. I think folks doing spontaneous ferments may also be more interested in the non-Saccharomyces yeast populations that are active early in the ferment before one strain or another of Saccharomyces grows large enough to take over and finish things off: the Pichias, Torulesporas, Hanseniasporas, etc.

I do find the theory in this article interesting, it made me think of the pesky wasps in my vineyard a little differently: The Role of the Social Wasp in Yeast Ecology: Thank Your Local Wasp for the Complexity of Your Wine

Very interesting article, thank you for sharing~ She has quite a few other articles that are quite compelling as well. I’m looking at my honey bees a little differently now too…

 

[user 38734]

It wasn’t too long ago a post like this would attract a litany of comments about native yeast fermentation being “too risky”, “a ticking time bomb”, and that your wines would smell and taste of “funk” and “barn yard” from people dancing naked in the forest. Fact is, hundreds of commercial winemakers (dedicated, intelligent craftspeople) produce outstanding native-ferment wines, many of them world class, so thankfully those days appear to be over.

Native yeast ferments, whole berry ferments, and partial or 100% whole cluster ferments are all becoming more and more common along with a more bare bones style of wine making which includes minimal SO2, extended macerations, more time on lees, longer barrel time, less or no new oak, and no fining or filtering.

These wines could have sediment (most don’t) and throw tartrates if cold (like any wine that isn’t cold stabilized).

While what’s popular may lean one way or another, in the end wine is subjective and eventually comes down to quality fruit, right? With most professions or hobbies, you do whatever it is hundreds or even thousands of times. With wine making, you’re lucky to get 30 or 40 shots on goal. We get so darn few opportunities to make wines, it’s key to continue to learn, refine and evolve. Make your wines your way, enjoy the hell out of them, and share them with as many people as possible.

 

[Ajmassa]

One think to keep in mind that most of these commercial natural ferments are doing it with much less risk then we would be since they are repeating the process year after year. They know their grapes front & back. Usually sourcing same fruit for years or growing own. And adding cultured yeast is really just unnecessary.
They use same barrels for multiple years- ensuring mlf will occur and be successful. (I assume they add bacteria when using new barrels)

I did a natural ferment in ‘18. (No yeast, so2 or even nutrients— tryin to go fully natural) Was from grapes i got from a 1st time source. It went dry. MLF however did not take naturally. But I left it as it was—- as nature intended it to be. In the end the wine was fantastic. (Btw I have had wines go thru mlf on their own accidentally)

 

[winemaker81]

It wasn’t too long ago a post like this would attract a litany of comments about native yeast fermentation being “too risky”

Without knowing more about the yeast growing in a given vineyard, a non-inoculated ferment is beyond my risk tolerance. My confidence is reduced by the fact that I have no idea if the grapes I purchase each year come from the same vineyard. Having 30 gallons of wine that I don't want is not a risk I'm interested in, and $1 USD per carboy of wine is a cheap price to pay.

I recommend commercial yeast for beginners, as we want them to have successful batches so they don't get discouraged. This is among the reasons EC-1118 is most often included in kits, as it helps ensure a successful result.

But if it is within someone's risk tolerance? Go for it!

I gave some thought to this. Given the history of hundreds of years of commercial wine production, it's very likely the yeast growing in a vineyard -- even one of relatively new hybrids -- is strain(s) that produce results we (humans) want. The yeast will propagate from the parents of the hybrids, from the air of the labs, and from the wineries were previous batches were fermented. Logically speaking, the risk of a batch yeast is probably rather low.

 

[user 38734]

One think to keep in mind that most of these commercial natural ferments are doing it with much less risk then we would be since they are repeating the process year after year. They know their grapes front & back. Usually sourcing same fruit for years or growing own. And adding cultured yeast is really just unnecessary.
They use same barrels for multiple years- ensuring mlf will occur and be successful. (I assume they add bacteria when using new barrels)

I did a natural ferment in ‘18. From grapes i got from a 1st time source. It went dry. MLF however did not take naturally. But I left it as it was—- as nature intended it to be. In the end the wine was fantastic. (Btw I have had wines go thru mlf on their own accidentally)

Spot on AJ.

But.....native MLF is not uncommon, even in new barrels - it just takes 4 or 6 months which is no problem if you are aging 20 to 30 months.

 

[Noontime]

Agreed, but the risk is certainly higher for home winemakers since they rarely know exactly where their grapes are coming from and what yeast strains are coming with them. I think more important to these online forums and groups is it's an even greater risk when you throw out the assumption they are making wine from grapes; when making fruit/country wines the chance of wild yeast either on the fruit or in the home will be optimal for that fruit has got to be pretty low.

 

[Nebbiolo020]

Wild fermentation’s are a risk you never know what you will get. You could get lucky or you might get vinegar, most wild yeasts will also not ferment dry and you sometimes will get 5-7% alcohol out of them and have to use a commercial yeast to finish the job. It can contribute interesting flavors and aromas though. I have gotten lucky the 2 times that I tried it but I feel it’s too risky to justify.

 

[sjjan]

I have been doing natural fermentation with success. I bought a few thousand kilos of Italian grapes coming from unknown vineyards in Italy and transported to The Netherlands in cooled transport in 2 days. Grapes were: Montepulciano, Grillo and Trebbiano. In total I have 5 Speidel tanks with in each about 250-270 liter of wine finished all with the primary fermentation.

With one of the tanks with Montepulciano in it, the natural fermentation did not kick in after 3-4 days, so I took some of the fermenting juice from the next tank with Montepulciano and moved it over to the tank with the Montepulciano not fermenting (about 10 liter) and inoculated this way the fermentation.

I started by bringing the temperature up to around 21 degrees Celsius to start the fermentation, then as soon as the fermentation started, I turned the heating element on and as soon as the temperature reached 24 degrees as a sign that it was really going, the cooling automatically kicked in and brought the temperature slowly down to 16 degrees Celsius plus/minus 1 degrees for the rest of the fermentation. As soon as the fermentation was almost done, I turned off the cooling to clean up and round up the primary fermentation.

All the tanks fermented to dry with ABVs of 12,5 to 13,5% (Italian grapes that had lots of sunshine). One tank with Montepulciano did not fully ferment to dry so far. The others all went down to an SG of around 0.992 or even lower, this one is sitting at 0.999 but still dropping a very small amount. But no worries, I can do "cuvage" or mixing of the wines in the end to get to a good product.

So far so good with wild/natural fermentation. Next week I have an opportunity to pick up some top Riesling grapes from the Alsace region from a friend who is a winemaker there. Hope to make just as good a wine (or better of course) as he does from it.

 

[Cynewulf]

Congrats! Sounds like everything is going well and I look forward to hearing what you think about the final product. Incidentally, you are doing some large quantities and have a really nice setup: are you just producing for family and friends or do you have other production goals?

 

[sjjan]

Incidentally, you are doing some large quantities and have a really nice setup: are you just producing for family and friends or do you have other production goals?

Well, I made 1250 liter of wine so far this year and will add another 260 or so liter of Riesling wine next week. That is a quantity too large to drink myself with my friends and family but too small to make any money with it. I did get all the legal work done, so can produce commercially and sell it. So, yes, I am selling a part of it to offset some of the costs I am making with making the wine but it is still more hobby than profession. I like doing it, so I might scale up.

 

[Cynewulf]

Well, I made 1250 liter of wine so far this year and will add another 260 or so liter of Riesling wine next week. That is a quantity too large to drink myself with my friends and family but too small to make any money with it. I did get all the legal work done, so can produce commercially and sell it. So, yes, I am selling a part of it to offset some of the costs I am making with making the wine but it is still more hobby than profession. I like doing it, so I might scale up.

Very, very cool. I’d love to hear more about how your commercial endeavor goes this year and if/how you develop it further.