Adventures in Wild Fermentation

[Cynewulf]

I thought I might document what I'm trying this year in case it helps anyone else out. I have a small vineyard in northern Virginia with about 75 grapevines that I've struggled to get going over the past four growing seasons. It's gone from all Cabernet Franc to about one third Cab Franc and two thirds hybrids due to disease and other things. I wasn't able to get much this year but am ready to get started making wine so bought three lugs of grapes from California through Washington Winemakers - Grenache, Carignan, and Syrah - along with a bucket of Grenache juice. My hope is to very roughly imitate a blend from a French winery in Fitou, Domaine Grand Guilhem, that I had recently that is 55% Grenache, 30% Carignan, and 15% Syrah with up to 15% of the bunches not destemmed. Not a fancy wine but exactly the kind of wine I love in France. I love old school, old world wines with savory notes, low/no oak, and a bit of acidity. It seems harder to find them in the States, at least at a price I can afford, so I'm hoping to learn how to implement some of what they do, including relying on wild, native, indigenous, ambient (whatever we're supposed to call them) yeasts and low sulfites if I can.

To prepare, I thought I'd try making a 'pied de cuve' or wild yeast starter from the 15 lbs of Cabernet Franc grapes I was able to salvage from my vineyard this year. I picked them Sunday, September 27 and destemmed and crushed them into a bucket. The must measured 18 brix that Sunday and on Tuesday morning there was clear fermentation activity. The SG dropped steadily by about .01 a day until it read 1.020 the morning of Sunday, Oct 4. It had a fruity smell and nothing to suggest spoilage so I decided to use it. One thing to note is that I have never made wine or brewed beer in this house so I don't think there should be any commercial yeast around (I'd actually feel a little better if there was as I reckon it could always jump in to finish the job). The closest winery is 3.5 miles away and there are some breweries a little closer so I suppose maybe their yeasts could make the trip into my vineyard or cellar but I have no idea.

October 3 I picked up the grapes and crushed them with @mainshipfred, reserving around 9-ish lbs of whole clusters and adding 3 gallons of the Grenache juice (kind of wish I had just done all grapes but too late). The starting gravity was 1.096 and pH 3.45. October 4 I added the pied de cuve in the afternoon and by the evening it was bubbling away. October 5 morning the SG was 1.080 with a 3" cap and in the evening SG was 1.070 with a thicker cap. I'm hoping for a relatively slow ferment and would like it to macerate for at least two weeks. I'd prefer longer but I'm starting to reach the limits of my adventurous risk tolerance.

I hope this is of interest and might help someone curious about wild ferments, etc. as I was only able to find a few posts from folks who have done it. I'll try to follow up from time to time to describe how it goes and would also be keen to hear from others that have tried similar or other interesting techniques; especially if you've been successful but even if you weren't.

 

[Boatboy24]

Following...

 

[BI81]

Interested to hear your progress, thanks for posting!

 

[Jbu60]

Very interested to hear how you make out..!

(In the meantime just want to share quick story from last week. My neighbour purchased 10 lugs of Central Valley California Cabernet Sauvignon grapes, brought them home, dunked all the grape bunches into a barrel of water, then pulled them out one at a time and rinsed them off with the garden hose and put them on a table to dry briefly before crush and destem. No additives were added, no yeast added, nothing. I assumed the worst would occur - that all the wild yeast were washed off and that the fermentation would be slow and perhaps stop short. BUT, by the end of the third day a huge cap had formed and the must was fermenting feverishly and had a great fruity smell. Ended up fermenting dry to 1.000 at pressing. The wild yeast survived indeed. I was shocked but very pleased as I'd like to try that myself...!)

 

[Rice_Guy]

we have to remember that all “cultured” yeast was once a “wild“ yeast.

 

[VinesnBines]

I was planning to buy some PV grapes from a local vineyard but the manager forgot and crushed everything on Oct. 1. I was out of town and asked him to put them in cold storage. When I finally picked them up the morning of Oct 5, they were starting to ferment...SG was 1.052. I went on and pitched my yeast and 18 hours later i was down to 1.040. I expect we were using a little wild yeast and whatever cultured spores were floating around the winery. I was planning a yeast combo anyway so I got a head start on the ferm.

 

[Cynewulf]

Very interested to hear how you make out..!

(In the meantime just want to share quick story from last week. My neighbour purchased 10 lugs of Central Valley California Cabernet Sauvignon grapes, brought them home, dunked all the grape bunches into a barrel of water, then pulled them out one at a time and rinsed them off with the garden hose and put them on a table to dry briefly before crush and destem. No additives were added, no yeast added, nothing. I assumed the worst would occur - that all the wild yeast were washed off and that the fermentation would be slow and perhaps stop short. BUT, by the end of the third day a huge cap had formed and the must was fermenting feverishly and had a great fruity smell. Ended up fermenting dry to 1.000 at pressing. The wild yeast survived indeed. I was shocked but very pleased as I'd like to try that myself...!)

Very interesting - thanks for sharing! I was a little nervous preparing the pied de cuve because there was a good rain a day or two before and I didn’t know if that would have an impact on the yeast but it seemed to start just fine. Based on what I’ve read, I’m also not sure how much depends on what is on the skins vs what is in the ambient environment. How long did it take to ferment to dry?

 

[Cynewulf]

we have to remember that all “cultured” yeast was once a “wild“ yeast.

Absolutely agree. To be honest, the more I read about this subject, the more I suspect that what I like in the wines I was describing is the result of limited activity by what we would consider spoilage organisms, maybe some brettanomyces and/or acetobacter. There is a smell and flavor in some so-called ‘natural wines’ from France and Georgia that I tend to describe as savory, prosciutto-like that I really like. I tasted it again recently after having read more about volatile acidity, and I’m starting to think the smell and taste I’m thinking of may actually be more of a balsamic note and possibly the result of a slightly higher level of VA than we would typically expect in a well made wine but still integrated and not overpowering. Playing with fire...

 

[CoteRotie]

I think UC Davis did a study a while back and found that just about all "wild" (i.e. uninoculated) yeast fermentations finished with a commercial strain (as checked by DNA analysis). However, I think those were all done in commercial wineries. If you've never made wine in this house maybe you have the potential for more "excitement".

 

[Cynewulf]

I think UC Davis did a study a while back and found that just about all "wild" (i.e. uninoculated) yeast fermentations finished with a commercial strain (as checked by DNA analysis). However, I think those were all done in commercial wineries. If you've never made wine in this house maybe you have the potential for more "excitement".

Excitement mixed with a little terror. I think I’ve seen that study. Originally I was going to wait until I’d had at least one season of using commercial yeast because I wanted to have it in the air to finish the job but the pied de cuve seemed to be working and I don’t stand to lose that much so figured what the heck. There’s a packet of yeast in the fridge if it gets stuck.

 

[Cynewulf]

Day 3:
AM: SG 1.050
PM: SG 1.040

Cellar temp: 66F
Must temp: 70F
Punch downs 3x daily

My commercial beer making brother on the west coast asked for more pictures:

 

[VinesnBines]

NIce! Faster than my wild/commercial ferm. Though I dropped from 1.040 at 6 am to 1.030 at 3 pm. I don't have so many bubbles but a cap of about 7 inches.

 

[Jbu60]

Very interesting - thanks for sharing! I was a little nervous preparing the pied de cuve because there was a good rain a day or two before and I didn’t know if that would have an impact on the yeast but it seemed to start just fine. Based on what I’ve read, I’m also not sure how much depends on what is on the skins vs what is in the ambient environment. How long did it take to ferment to dry?

7 days

 

[sour_grapes]

Excitement mixed with a little terror.

There is a fine line between "terror" and "terroir"!

 

[Cynewulf]

Day 4:
AM: SG 1.026
PM: SG 1.018

Day 5:
AM: SG 1.008
PM: SG 1.004

Cellar temp: 66F
Must temp: 70F
Throttling back to punch downs 1-2x daily

 

[Cynewulf]

Some of these are guesses as everything is slowing down and I don’t have a final gravity hydrometer.

Day 6:
AM: SG 1.000
PM: SG 0.999

Day 7:
AM: SG 0.998
PM: SG 0.997-ish

The plan, such as it is, is to punch down lightly once a day now to wet the cap, then press off the skins when the cap falls.

 

[mainshipfred]

Absolutely agree. To be honest, the more I read about this subject, the more I suspect that what I like in the wines I was describing is the result of limited activity by what we would consider spoilage organisms, maybe some brettanomyces and/or acetobacter. There is a smell and flavor in some so-called ‘natural wines’ from France and Georgia that I tend to describe as savory, prosciutto-like that I really like. I tasted it again recently after having read more about volatile acidity, and I’m starting to think the smell and taste I’m thinking of may actually be more of a balsamic note and possibly the result of a slightly higher level of VA than we would typically expect in a well made wine but still integrated and not overpowering. Playing with fire...

I think I may have posted this before. I took a short vintner's course and one of the classes we were discussing faults. A couple of bottles of wine with brettanomyces were opened to sample. Not sure what it's supposed to taste like but I didn't find it offensive at all, in fact neither did the majority of the class. Acetobactor on the other hand is a different story.

 

[mainshipfred]

Some of these are guesses as everything is slowing down and I don’t have a final gravity hydrometer.

Day 6:
AM: SG 1.000
PM: SG 0.999

Day 7:
AM: SG 0.998
PM: SG 0.997-ish

The plan, such as it is, is to punch down lightly once a day now to wet the cap, then press off the skins when the cap falls.

I've never had a cap completely fall even at .994 or 5. Just have to assume it's the CO2 keeping it afloat.

 

[Cynewulf]

I've never had a cap completely fall even at .994 or 5. Just have to assume it's the CO2 keeping it afloat.

Thanks, Fred. I maybe should have said that the plan was to let it go for another week or two or until the cap falls, whichever happens first. I was a little disappointed that fermentation went as quickly as it did, even though the must temp never seemed to go over 70F. I may cover the cap with some plastic wrap to limit oxygen contact since I don’t have a CO2 tank yet.

 

[Cynewulf]

I think I may have posted this before. I took a short vintner's course and one of the classes we were discussing faults. A couple of bottles of wine with brettanomyces were opened to sample. Not sure what it's supposed to taste like but I didn't find it offensive at all, in fact neither did the majority of the class. Acetobactor on the other hand is a different story.

I probably should have said acetic acid or volatile acid, as it’s present in all wine to varying degrees: There's Vinegar In My Wine!. I suspect it may be what I’m tasting in the low/no sulfited French wines I like in a slightly higher concentration than we typically expect to find in a bottle of wine.
I really like this interview with another of my favorite winemakers, Mattieu Lapierre: Terroir and Technique in Beaujolais: Talking Natural Wines with Mathieu Lapierre | Wine Spectator. His father Marcel reintroduced a lot of the traditional ‘natural’ techniques to the cru Beaujolais Morgon region but Matthieu explains why he thinks complete nonintervention is unwise. He actually will tolerate 400-600 mg/L of VA depending on the richness of the wine, but works hard to control it. I like this quote: ‘VA “is a component of wine, but you should never seek it out,” he says and laughs. “There is always enough!”’ I’ve had both the Lapierre Morgon and their Raisins Gaulois a couple of times and both are delightful. I actually have a bottle of Georgian wine I brought back on my last trip to Tbilisi that I want to share with you one of these times we get together that I think is a fair example of what I’m thinking of. I’d be interested in your reaction.