What type of wild yeast on grapes? Anything sour?

[CarbonTom]

Last spring I noticed that there were some wild grapes growing out back. They may not be wild, I seem to remember my old man mentioning that the previous owner grew them for wine. But they have been growing wildly, and un-cared for for at least the past 15 years.

Anyways, I have been learning a lot about wild beers recently, and wonder if the cloudy (must?) on their skins are yeast, and can they be used to make an interesting beer?

Somewhat separately, would there be anything worth trying of trying an open top spontaneous fermentation next to the vine? (its like 6-8 feet tall at the peak of the summer). Or is it not big enough to be used like the orchard method?

I'm a super noob to wild beers, I hope this isn't a redundant question here, I couldn't find anything searching.

Thanks!

 

[mnick12]

Grapes are usually covered in yeast,

It may not be anything sour like, but it could be interesting. I would drop an crush a few in a like 10-15ml of wort and let it ferment.

 

[Agate]

I've been growing up some captured yeast from my grape vines since last October. The first couple times I fermented a starter, it stalled out at around 1.7%ABV, but the third time it took a gallon test batch from 1.055 to 0.998.

No idea what kind of yeast was on the grape skins, but my guess would be mostly sacch of some kind. It started developing a slight pellicle once dry-hopped, so I'm assuming some type of brett as well.

The first gallon is still bottle conditioning, but when I bottled it it was fruity, tart, and spicy. I have 4 gallons going now in primary, and it's throwing some crazy aromas!

Not to say you'd have anything similar on yours, but I think it's definitely worth a shot! As long as your starter doesn't get moldy or rancid, don't give up on it if you don't get good results right off the bat.

 

[kbindera]

Grapes are often used to make sourdough bread starters. You might try adapting some of the techniques that bakers use to get the souring bacteria going from your grapes. Here's an interesting read:
http://www.kingarthurflour.com/recipes/grape-sourdough-starter-recipe

 

[CarbonTom]

Grapes are often used to make sourdough bread starters. You might try adapting some of the techniques that bakers use to get the souring bacteria going from your grapes. Here's an interesting read:
http://www.kingarthurflour.com/recipes/grape-sourdough-starter-recipe

Wow thats a pretty cool idea. I will try that out.


I will definitely try making an array of starters based on everyones suggestion. I assume they should all be on the weak OG side, since I would be ramping them up from very small numbers. How low do you go? 1.020?

 

[Agate]

I started with about 2C of 1.030 unhopped wort. Probably should have started lower, but it was second runnings from an AG batch, or at least what ran out of the spent grain at the end of brew day. Put it in a quart bottle, and snipped some fresh grapes with a sanitized scissors directly into the bottle. Here's how it looked the next day - fermentation had already started.
View attachment ImageUploadedByHome Brew1426691281.453650.jpg

 

[CarbonTom]

That looks like the easiest way to do it. You boiled it right?

 

[Agate]

Yeah, just for 5 minutes or so to sanitize it. It took two more repitches before it did anything worthwhile, and I'm assuming that was because it took awhile for certain strains in there to grow up enough of a population to take over, but now it's a beast! Haven't had anything ferment a malt-based wort below 1.000, but this yeast cocktail did.

 

[CarbonTom]

That's awesome, come springtime I will be doing some experiments!