Adventures in Wild Fermentation

[Nebbiolo020]

Thanks, the vines were planted in 2017. I haven’t had it tested but as far as I understand and can tell the soil is clay loam with equal parts clay, silt, and sand.

Cool yeah then this year is really the first year you would want to harvest grapes from them I have a vineyard that I planted between 2015-2019. And my earlier plantings are just finally starting to produce good yields. My Sauvignon blanc was the exception it made a full crop the year after I planted it and I just let it and now this year they are loaded again.

 

[Cynewulf]

I pulled the trigger on the Cab Franc yesterday. I wanted to let it hang for another week or two but was looking at this:


i ended up with about 35 lbs, less than I was hoping for but better than nothing:


Not too bad looking, though more uneven ripening and shot berries than I realized. I tried to remove as many of those as I could in the vineyard. The clusters were tiny compared to last year, I suspect because the vines were defoliated at the end of last August with unripe clusters still on them and weren’t able to store enough carbohydrates for this year. I left them to cool off overnight in my cellar then crushed today, leaving 4 lbs of whole clusters.

Initial numbers look better than I expected: 1.088 SG and 3.4 pH. Expect fermentation to start spontaneously tomorrow or the day after.

 

[Nebbiolo020]

I pulled the trigger on the Cab Franc yesterday. I wanted to let it hang for another week or two but was looking at this:
View attachment 78014

i ended up with about 35 lbs, less than I was hoping for but better than nothing:
View attachment 78015

Not too bad looking, though more uneven ripening and shot berries than I realized. I tried to remove as many of those as I could in the vineyard. The clusters were tiny compared to last year, I suspect because the vines were defoliated at the end of last August with unripe clusters still on them and weren’t able to store enough carbohydrates for this year. I left them to cool off overnight in my cellar then crushed today, leaving 4 lbs of whole clusters.
View attachment 78016
Initial numbers look better than I expected: 1.088 SG and 3.4 pH. Expect fermentation to start spontaneously tomorrow or the day after.

Nice, grapes look good and I think the numbers are pretty good as well. I am eager to hear about how it turns out.

 

[tkmorita]

Great post! And I appreciate all the follow-up!

I’m a homebrewer just about to start my journey into wine. I brew a lot of mixed fermentation, spontaneous, and brett beers and am excited about the idea of doing a spontaneous wine. I’ve tried to gather as much information as I can about tips on spontaneous but there isn’t much out there.

Anyway, I’m likely going to obtain about 100-150 lbs of Sangiovese from a commercial vineyard. They aren’t biodynamic or organic certified, however, there should still be plenty of wild stuff on there, correct? I hear how risky spontaneous wine is, but not much evidence to back that up as long as quality processes are implemented…controlled fermentation, minimal oxygen post fermentation, etc.

I hear great things about prolonged skin contact, and increased extraction with higher ferm temps, but worry about oxygen pickup if it finishes too soon. I figure a slow lag phase with spontaneous fermentation can help with this. However, how do you balance ferm temperature? From my understanding, a typical red ferment is 70-85, with higher temps promoting more extraction, but making fermentation quicker. I’d ideally want ~2 wk skin contact time.

 

[Cynewulf]

Great post! And I appreciate all the follow-up!

I’m a homebrewer just about to start my journey into wine. I brew a lot of mixed fermentation, spontaneous, and brett beers and am excited about the idea of doing a spontaneous wine. I’ve tried to gather as much information as I can about tips on spontaneous but there isn’t much out there.

Congrats on getting started in wine! The limited amount of practical info I was able to find was one of the inspirations for this post. I know it’s not for everybody but I figured there’d be a few curious people out there looking for information/experience as I was (still am).

Anyway, I’m likely going to obtain about 100-150 lbs of Sangiovese from a commercial vineyard. They aren’t biodynamic or organic certified, however, there should still be plenty of wild stuff on there, correct?

There should be. My vineyard is definitely not organic. Not because I wouldn’t like it to be, I’ve just learned that it’s not possible if I’m going to have a part-time hobby vineyard in Virginia. I spray with Mancozeb, Captan, and Myclobutanil at regular intervals (respecting pre harvest intervals). In spite of that I’m kicking off my fourth spontaneous ferment and haven’t had an issue yet.

I hear how risky spontaneous wine is, but not much evidence to back that up as long as quality processes are implemented…controlled fermentation, minimal oxygen post fermentation, etc.

Agreed. I’ve seen a lot of warnings about the risk but no actual negative experiences being related, though I’m certainly open to hearing about them. As you said, keep things reasonably clean, limit oxygen post ferment, etc. I’d suggest that includes limiting rackings as well. For now I’m racking once off the gross lees then two weeks before bottling, unless there is an H2S or other issue. This seems to be the protocol of a lot of the natural wine producers I follow and it seems to be working so far. I’ve seen theories and a few academic papers suggesting that fermenting on stems and/or lees contact may help reduce the need for SO2 additions. My personal preference is to limit or eliminate SO2; not for health or philosophical reasons, but for the microbiological diversity and related flavor potential. Again, not suggesting anyone else do this if they’re not comfortable with it, that’s just me and the wines I’ve enjoyed the most have been low or no added sulfites.

I hear great things about prolonged skin contact, and increased extraction with higher ferm temps, but worry about oxygen pickup if it finishes too soon. I figure a slow lag phase with spontaneous fermentation can help with this. However, how do you balance ferm temperature? From my understanding, a typical red ferment is 70-85, with higher temps promoting more extraction, but making fermentation quicker. I’d ideally want ~2 wk skin contact time.

I wanted a long slow ferment too if you saw at the beginning of this thread, though it didn’t work out exactly as I hoped. I suspect that was because I used the pied de cuve starter so ended up inoculating with a pretty healthy wild culture and going to dry after only six days. I still left it on the skins for another week with no issues. This year I’m not using a starter but crushing and letting everything start on its own and have had nice, slow ferments of about ten days to two weeks. I personally think you’re good macerating for another week after you get to dry as the must is saturated with CO2 and other antioxidants, but theoretically you want the keep the cap wet. (I say theoretically because I’ve seen a study where they actually observed less VA with no punch downs).

I don’t control the temperature but ferment in my cellar which stays in the mid 60s in the summer and my must temps seem to stay around 70. I think letting the ambient yeast do their thing at the activity and alcohol levels they are comfortable with help with that, whereas relying only on saccharomyces from the beginning may result in a more vigorous ferment at higher temperatures. The non-saccharomyces yeasts are always far more abundant and kick things off while the saccharomyces population slowly builds to finish things off. If you have the temperature control ability and wanted to, I know some natural winemakers will ferment in the 70s for the most part then let it finish warmer at the end. I honestly don’t know what that gets you but it’s an option if you wanted to couple a longer ferment with some warmer temperatures at the end to get the extraction you’re looking for.

Full disclaimer: all of this is based on my limited experience along with a few theories/opinions and some research, YMMV. If you’re looking for more info in English, I’ve found this blog to be full of interesting practical details from mostly French winemakers that practice ‘natural winemaking’ techniques: Wine Tasting, Vineyards, in France. I learned of a technique one winemaker in the Loire uses where he fills an amphorae full of whole clusters of Cabernet Franc submerged/topped with juice from previously pressed grapes to eliminate oxygen and leaves them sealed until about Christmas before pressing. I may try that with a sample of my Marquette next year if I get a large enough harvest.

I hope this is helpful and look forward to hearing about what you decide to do and how it turns out!

 

[user 38734]

@Cynewulf - Excellent, thank you!

 

[tkmorita]

…For now I’m racking once off the gross lees then two weeks before bottling, unless there is an H2S or other issue. This seems to be the protocol of a lot of the natural wine producers I follow and it seems to be working so far. I’ve seen theories and a few academic papers suggesting that fermenting on stems and/or lees contact may help reduce the need for SO2 additions. My personal preference is to limit or eliminate SO2; not for health or philosophical reasons, but for the microbiological diversity and related flavor potential. Again, not suggesting anyone else do this if they’re not comfortable with it, that’s just me and the wines I’ve enjoyed the most have been low or no added sulfites.

I’m in the same boat with SO2…would like to minimize as much as possible for microbial expression and complexity. I’m curious though, what is the reason for the racking 2 weeks before bottling? Clarity? Adding a small amount of sulfite? I’m fine with a little sediment in the bottle so I was planning on just doing once after the initial gross lees, and then bottling straight from fermenter whenever I decide it’s ready

.you have the temperature control ability and wanted to, I know some natural winemakers will ferment in the 70s for the most part then let it finish warmer at the end. I honestly don’t know what that gets you but it’s an option if you wanted to couple a longer ferment with some warmer temperatures at the end to get the extraction you’re looking for.

This sounds like a good plan. I know from beer brewing it’s a good idea to ramp up just as fermentation is finishing. It helps make sure you fully ferment out (a lot more polysaccharides to work through in beer), and helps clear diacetyl, acetaldehyde, and potentially sulfur.

Really appreciate the response, helpful tips, and great resource. I’ll be sure to post about my experience as long as I get my grapes!

 

[franc1969]

what is the reason for the racking 2 weeks before bottling?

Both reasons you stated, plus evening out flavors through the wine volume. Particularly if you have been aging on fine lees or with oak.

 

[tkmorita]

This past Saturday I got my grapes! 150 lbs of Sangiovese and 100 lbs of Cab Franc. They were a little more ripe than ideal:

sangio: 26 Brix, pH 3.56
Cab Franc: 28.2 Brix, pH 4.06

I ended up pulling off a bit of juice on each (saignee) for a separate rosé and then diluting each bin to about 24 Brix (Rosés diluted to 21 Brix). I also added some Fermaid O and tartaric acid to bring both pH’s closer to 3.4 (I’m not against adding stuff, just want to have the complexity of the wild stuff fermenting it rather than a commercial isolate).

I’ve been mixing things up about three times a day. Hopefully fermentation kicks up in the next day or two.



sangiovese on day 1:

Cab franc on day 1:

Sangiovese at 48hrs:

Cab franc at 48 hrs:

 

[mainshipfred]

I left all my inhibitions behind and tried a wild ferment on my Viognier. Mostly because the winery I got the grapes from said that is how they ferment theirs. So far so good although it is going slowly.

 

[Cynewulf]

I left all my inhibitions behind and tried a wild ferment on my Viognier. Mostly because the winery I got the grapes from said that is how they ferment theirs. So far so good although it is going slowly.

Can’t wait to hear how it goes, Fred!

 

[tkmorita]

So there were subtle signs of fermentation on both sets of grapes (Sangio and Cab Franc) by day 3, and then by day 4 there was a nice cap starting to develop. I’ve been punching down 3 times a day and the temp has held pretty steady around 72-75F.

I happened to also have a forced fermentation test going (small juice sample on a stir plate with a heating pad to keep it closer to 90F), and unfortunately that test seems to have stalled at about 7% abv. Day 9 and day 10 readings were the same.

I ended up making a small starter of Lalvin Bourgovin RC212 and pitching it into each batch on day 10 to ensure fermentation can complete. I really wanted to go 100% wild, but having that fermentation test stall made me nervous. At least the early portion of fermentation was all wild.

It’s now day 11 and I’m at 14.5 Brix. Based on this rate, I should be close to dry around day 17 (unless that Bourgovin really starts to speed things up).

punching that Sangio cap, day 10:

 

[mainshipfred]

Can’t wait to hear how it goes, Fred!

Well it got stuck around 1.015. The initial brix was 28 though I think it was higher since I didn't take the reading until the second day and they were overly ripe to begin with. It first got stuck at 1.030 so I added a cultured yeast but I'm guessing the alcohol level might have been too high already. I used D47 and BA 11. Today I'm preparing a starter using a champagne yeast I have. We'll see how it goes. On the bright side there is no H2S or any off putting odors and it actually tastes fine, just a little sweet and of course harsh.

 

[Joe B.]

This is a great read, thanks for all the posts. I keep a fresh batch of EC1118 yeast on hand each year in case a ferment get's stuck. Only had to use it once and it did the job.

 

[mainshipfred]

The starter appears to be working. I doubled the recommended amount of Go-Ferm and yeast and added some DAP. Then throughout the course of the day added about 2000 ml of the wine to get it used to the high alcohol. This morning there is activity and it went from 1.015 to 1.011 so I'm thinking it will finish.

 

[Cynewulf]

That starting Brix does seem pretty high. Does the winery you got them from usually do a spontaneous ferment when it’s that high, and/or are they going for some residual sugar? As far as I can tell, the ‘natural’ winemakers in France that I follow don’t seem to let their grapes hang that long unless they are pursuing a particular style with residual sugar at the end. On the other hand, they’ll talk about the fermentation taking months or even over a year to complete sometimes, which puzzled me with my limited experience of having fermentation complete after about two weeks. Makes me wonder if some fermentations actually stick or just start going really slow…. Hope you’ll be happy with the end results.

 

[mainshipfred]

That starting Brix does seem pretty high. Does the winery you got them from usually do a spontaneous ferment when it’s that high, and/or are they going for some residual sugar? As far as I can tell, the ‘natural’ winemakers in France that I follow don’t seem to let their grapes hang that long unless they are pursuing a particular style with residual sugar at the end. On the other hand, they’ll talk about the fermentation taking months or even over a year to complete sometimes, which puzzled me with my limited experience of having fermentation complete after about two weeks. Makes me wonder if some fermentations actually stick or just start going really slow…. Hope you’ll be happy with the end results.

It is their style and they do take it to dry although when you read their description they call it sweet with 1% residual sugar. Since the grapes were so ripe it almost appears it's going to be a somewhat of an orange wine even though I pressed immediately after crush. If you would have said really, really, really slowly I might have agreed but it stayed at 1.015 for over a week. I found out the winery's also got stuck so I don't feel so bad. When the time comes I'll do bench trials watering it back though as I mentioned it is really not that bad for such a young wine. Perhaps you might want to try it sometime.

 

[Cynewulf]

Here’s a brief update on last year and what’s going on this year. I bottled everything back in May. The Marquette was nice but a little thin - a known issue with hybrids, I think. I blended in 10% Cabernet Franc and I think it made a significant improvement. I’ve opened a bottle or two since then, but think it needs another few months to a year or beyond to fully integrate as the acid seems a little out of sync with the fruit, but I think it’s improving with time.

The Itasca came out very nice and my wife really likes it. It is very different than any white wine I’ve tried, with flavors of apple, pineapple, and honey, and a surprising and unusual curry spice finish.

I think the Cabernet Franc is promising and also will benefit from some time.

So far this year I’ve harvested the hybrids on August 5 and 6, a little earlier than I wanted, but I had some critters that were really starting to go after them. I ended up with around 85lbs of Marquette again and about 45lbs of Itasca.

This year I’m experimenting with carbonic maceration. I filled a 3 gallon Fermonster with whole Marquette clusters and added a quart of juice from crush. After about two days the juice showed fermentation activity. I’m debating whether to press this Friday or to fill it with free run from my traditionally macerating Marquette for 90 days then press replicating a technique used by Sebastien David for his Coef cuvée but I’m leaning toward the latter.

 

[Cynewulf]

Opened up the fermonster yesterday. Made the dumb rookie mistake of sticking my nose in it and got a painful blast of CO2 in the face. I tasted a couple of the berries on top and they were delicious and just as I’d heard advertised: prickly carbonation, fruity and slightly boozy. I was tempted to press them right then but I’d like to experiment further so filled it up to the top with 1.25 gallons of free run from my traditionally macerating Marquette and will leave it for 90 days.

If this is successful, next year I may get another fermonster to be able to do one carbonic maceration and one extended steeping/maceration like this.

 

[Cynewulf]

The airlock on the fermonster was good for a week or two after I topped it up but then wine started pushing out through it and making a bit of a mess. I’ve switched to a blow off tube and that seems to be working, though even then at first there was enough pressure to push the bung out. I tasted this morning and am very happy so far - rich and floral and very different than my traditionally macerated Marquette. Still a lot of fermentation activity. Only two months to go before pressing.



Interesting how the color is leeching out of the grapes. The wine samples I’ve taken so far have a deeper purple color than my other Marquette, which tends toward red.


I opened a bottle of my 2021 Marquette from last year and am very happy with how it is developing. The fruit and acid are coming into balance, with nice cherry flavors and the savory finish that I love in natural wine. The color seems stable without the browning I’ve seen in some hybrid wine. This was 100% Marquette and not the blend with 10% Cabernet Franc I did, so it is very light on tannins - maybe even a little too thin. I think in another 6 months to a year it’s going to be very good.