Interesting Natural Ferment Article

[cmason1957]

I have greatly changed my fear of "wild fermentations" after reading this article https://daily.sevenfifty.com/the-science-of-winemaking-yeasts/

For those who don't choose to read it, first thing that stood out to me: "According to Jamie Goode’s Authentic Wine, only about 20 percent of wine made around the world is fermented by yeast cultures that have deliberately been added to the batch—the rest depends on wild yeasts already present to do the job." That number sounds way low to me, but who knows. I would think it maybe ought to be the other way around where 20 Percent of the wines are made by natural fermentations. Who knows.

Second thing, a group of scientists, in conjunction with vineyard owners from Willamette Valley in Oregon did a natural ferment and every day did DNA fingerprinting of the yeast actually present. "By the time we got to 10 percent sugar, every time, all the vineyard yeasts were gone.” “The yeasts that are fermenting your wine are not vineyard yeasts,” explains Ken Wright. “They’re the [S. cerevisiae] yeasts that have a foothold in your house. In each winery, they’re hanging out the whole time, just waiting for that next gob of sugar to come down the road.”

It's an interesting read and for the three juice buckets I will be getting sometime soon, I plan to let the natural yeast just go and see what happens. I expect them to fully ferment and make an interesting wine. This isn't for everyone and I don't necessarily even recommend it, but it does sound fun and different.

 

[mainshipfred]

I have greatly changed my fear of "wild fermentations" after reading this article https://daily.sevenfifty.com/the-science-of-winemaking-yeasts/

For those who don't choose to read it, first thing that stood out to me: "According to Jamie Goode’s Authentic Wine, only about 20 percent of wine made around the world is fermented by yeast cultures that have deliberately been added to the batch—the rest depends on wild yeasts already present to do the job." That number sounds way low to me, but who knows. I would think it maybe ought to be the other way around where 20 Percent of the wines are made by natural fermentations. Who knows.

Second thing, a group of scientists, in conjunction with vineyard owners from Willamette Valley in Oregon did a natural ferment and every day did DNA fingerprinting of the yeast actually present. "By the time we got to 10 percent sugar, every time, all the vineyard yeasts were gone.” “The yeasts that are fermenting your wine are not vineyard yeasts,” explains Ken Wright. “They’re the [S. cerevisiae] yeasts that have a foothold in your house. In each winery, they’re hanging out the whole time, just waiting for that next gob of sugar to come down the road.”

It's an interesting read and for the three juice buckets I will be getting sometime soon, I plan to let the natural yeast just go and see what happens. I expect them to fully ferment and make an interesting wine. This isn't for everyone and I don't necessarily even recommend it, but it does sound fun and different.

I'm with you on the 20% the other way around. The only thing about you experiment with the juice buckets is you never know if cultured yeast was added or not. These juice bucket manufacturers need to quit being so secretive, the process is not rocket science. BTW, I didn't read the article just you commentary.

 

[stickman]

I will admit that most interviews with winemakers seem to indicate that they go with uninoculated fermentation, but most of those interviews are with small higher end producers. I can't imagine the large producers not using cultured yeast, for example Gallo might produce 20% of the US wine alone.

I think uninoculated fermentation would be fun, but I pay too much for the grapes to take the risk. Kloeckera apiculata is a major player at low temperatures during the beginning of fermentation, and as long as they don't get too far out of control, the fermentation will be fine. One of the compounds Kloeckera apiculata produces is ethyl acetate (nail polish aroma), and if you stay below the 50 to 90ppm range maybe its interesting, but cross over to the 120ppm detectable range and it's now a fault. The starting cell count in the must (which we normally don't know) is a big factor, so good clean undamaged fruit is important. Kloeckera tolerates 70+ ppm SO2 so don't look to sulfite for much help with control, the main control is competing yeast and rising alcohol content. Kloeckera also produces acetic acid, which acts in combination with rising alcohol content to cause stuck fermentations.

The upside of uninoculated fermentation might be enhanced mouthfeel and some interesting aromas, the downside could be bad.

 

[Adam Beck]

Cool read, interesting how two different groups came to two separate conclusions about how much of the yeast was from the vineyard vs the winery.

It's an interesting read and for the three juice buckets I will be getting sometime soon, I plan to let the natural yeast just go and see what happens. I expect them to fully ferment and make an interesting wine.

Keep in mind your juice has probably been sulfited, and any indigenous yeast is probably dead. You may end up getting it kicking from ambient yeast from the room you ferment in, but if you’re hoping for vineyard yeast, I think it’s doubtful it’s still living.

I mostly drink wine made with native yeasts, I think they just end up being more interesting. Some are definitely less “crowd pleasing” than more commercial wines, but I personally prefer quirky over pleasant. I’ve got some wines brewing that are with commercial yeast right now, but what I’m most excited about is a 3 gallon carboy of Cab Franc made from fresh grapes where I just let the native and ambient yeast do it’s thing. Ended up needing some yeast nutrient, and I’m thinking about adding some french oak sticks, but other than that there’s been no additives so far. It’s a little higher than I’d like on the pyrazines, but other than that it’s settling into its flavors really well, with a *ton* of complexity and a fair amount of it being earthy notes. If anything I’m hoping some of the complexity gets focused because at a couple months in its maybe too all over the place in terms of palate.

 

[jburtner]

Interesting. How long does it take to ferment like this? How about frozen must buckets?

Cheers,
Johann

 

[FXibley]

this will be my 6th year making wine and i have only ever done spontaneous ferments from grapes with crush taking place up at the farm i get my grapes from. i haven't had any issues with stuck ferments or off aromas so far. It does take a couple days for fermentation to really get going. I also have never added So2 or done any acid adjustments. I do add malolactic bacteria and when i bottle i add potassium sorbate because i backsweeten. The wine i turn into sparkling i just add sugar when bottling in champagne bottles.

this article was an interesting read

 

[Adam Beck]

Interesting. How long does it take to ferment like this? How about frozen must buckets?

My cab franc took four days for fermentation to start, and then about nine days to get to the point where I moved it to a secondary vessel. I’d check with your supplier on whether it had SO2 added prior to freezing, people are so quick to add SO2 these days that I imagine anything sold commercially has already been sulfited, but I may be wrong.

 

[BI81]

This is a very interesting article. It would be interesting to know how many of these commercial winemakers that are using native ferments are adding nutrients, and if they are not what the correlation between flavor/aroma/mouthfeel and fermentation time is to the actual yeast strain vs the stress that the yeast is going through to complete the fermentation. I'd also be interested to know what percentage of commercial winemakers that are using native ferments are adding enzymes or if they are truly 100% native throughout their process.