[chandlergr]

I regularly make beers with wild yeast I isolate from around my city (use malt agar plates to streak for isolation and then step up to pitchable quantities). One of the last beers I made however, I think got contaminated with some wild oxidative yeast because it has been slowly fermenting for about over a month now and has dropped from 1.066 to 1.004 (normally stops around 1.010) and is slowly exhibiting some acetate and ethyl acetate. I was thinking this might be a great opportunity to break in a used whiskey barrel and wild mixed culture blend I cultured in a similar way. My question is it too late to get any noticeable funk or souring from a mixed culture when the beer already has such a low gravity? How much 'food' do brett and pedio need to express their respective characters? Should I even bother?

[klickitat jim]

I dont think you're going to get rid of EA though. Same with acetic, for example. And reportedly those don't blend away very well either. Kind of like throwing good money after bad.

As to how low can you pitch brett and still get something, I think anytime. But dont expect miracles.

[AmandaK]

Agree with Jim.

Once you have nail polish, there is no no going back. Nail polish is a dumper in my house.

[reverseapachemaster]

Agreed. Do not do that to your barrel.

[toby]

I dont think you're going to get rid of EA though. Same with acetic, for example. And reportedly those don't blend away very well either. Kind of like throwing good money after bad.

As to how low can you pitch brett and still get something, I think anytime. But dont expect miracles.

Yep.  Don't do that to your barrel.  You'll ruin it.  The pros have differing opinions on what to do with a barrel once it has gone bad in that way (but they pretty much all agree that ethyl acetate and/or strong acetic produced by a barrel make it bad).  Jester King usually takes theirs out of production in some way.  New Belgium will occasionally keep one or two around for the occasional blend (with acetic producers but not ethyl acetate).

[brewinhard]

+1.  Neither of those compounds will age out.  In fact, I have only noticed an increase in their production during aging many times.

[chandlergr]

hmm the acetate and ethyl acetate are nowhere near strong enough to ruin the batch yet, barely above threshold. that is to say, those flavors are not my concern really, at least not yet; at low low levels I think both add some nice dimensions of complexity to sours. of course they can easily become overwhelming, but they are certainly not there yet; I do not know where I gave the impression I was trying to 'age them out.'

The beer still tastes really nice actually, and I was wondering if I could continue to add something to it considering the direction it has unintentionally taken. Many wild yeasts found in barrels, including brett, will oxidize ethanol to acetate (which will then bind with ethanol to form ethyl acetate) over time, so adding the beer to the barrel hardly seems dangerous (there are probably all kinds of oxidative yeasts in there already).

Anyways, since it seems like I may not be able to derive much from the mixed culture with such a low gravity already, I may just wait until the next batch.

[brewinhard]

You could boil up some maltodextrin and add that back to the beer.  Saccharomyces cannot consume that and your wild yeast/brett/bacteria will enjoy the long term munchies. 

[reverseapachemaster]

I would agree with your premise if you knew no further acetate will be formed in the beer. However, there is a good probability that whatever has been creating acetate will continue to do so and over time that beer will become unpleasant with excessive ethyl acetate. If that is the case and you put that in the beer then you may have a barrel that always creates ethyl acetate. Subsequent cleanings might get rid of the problem but might not. In my opinion, and seemingly the opinion of many others in this thread, is that the risk of creating a bad barrel is not worth it.

[chandlergr]

You could boil up some maltodextrin and add that back to the beer.  Saccharomyces cannot consume that and your wild yeast/brett/bacteria will enjoy the long term munchies. 

This is a good idea for feeding mixed cultures without feeding sacc. I will keep this in mind. Thanks.

I would agree with your premise if you knew no further acetate will be formed in the beer. However, there is a good probability that whatever has been creating acetate will continue to do so and over time that beer will become unpleasant with excessive ethyl acetate. If that is the case and you put that in the beer then you may have a barrel that always creates ethyl acetate. Subsequent cleanings might get rid of the problem but might not. In my opinion, and seemingly the opinion of many others in this thread, is that the risk of creating a bad barrel is not worth it.

Ok sounds good. This is something I wish I could experiment with if I had more barrels, but since I only have the one and have zero personal experience using them, I will trust this threads advice. Thanks!

[erockrph]

I'm a little late to the conversation, but I think a lot of sour beer brewers have come around on the thought that you need to leave food for Brett to produce it's typical flavor profile. If the appropriate flavor precursors are available, Brett will happily metabolize these without needing a significant carbohydrate source.

I heard a recent interview with Allagash where the brewers stated that they mash low to try to get their primary fermentation to finish as dry as possible when they're planning on adding Brett to the secondary. This lets them bottle a batch much sooner since they don't need to wait as long for the Brett to get close to terminal gravity. Their Brett beers are fantastic, so they must be doing something right.

[homoeccentricus]

I'm a little late to the conversation, but I think a lot of sour beer brewers have come around on the thought that you need to leave food for Brett to produce it's typical flavor profile. If the appropriate flavor precursors are available, Brett will happily metabolize these without needing a significant carbohydrate source.

I heard a recent interview with Allagash where the brewers stated that they mash low to try to get their primary fermentation to finish as dry as possible when they're planning on adding Brett to the secondary. This lets them bottle a batch much sooner since they don't need to wait as long for the Brett to get close to terminal gravity. Their Brett beers are fantastic, so they must be doing something right.

This is not what Russian River recommends. They say the opposite (for Supplication). And I guess they also must be doing something right. 

[kylekohlmorgen]

...Brett will happily metabolize these without needing a significant carbohydrate source...

This is the answer to the thread subject (at least for Brett).

Brett doesn't need a carbohydrate (sugar, dextrin) source to contribute flavor.

Brett needs carbs and oxygen for growth, so if you pitch a small amount in secondary it may take longer to get to the desired flavor profile. Obviously other factors play into the rate of flavor contribution, i.e. temperature, competing organisms, pH, etc. etc.

Pedio does need a carb source to produce lactic acid, but most strains can break down complex starches leftover by sacch fermentation (and even some left by Brett).

Adding 'food' (sugar, dextrin) to secondary will really just result in more alcohol from fermentation by brett.

[erockrph]

I'm a little late to the conversation, but I think a lot of sour beer brewers have come around on the thought that you need to leave food for Brett to produce it's typical flavor profile. If the appropriate flavor precursors are available, Brett will happily metabolize these without needing a significant carbohydrate source.

I heard a recent interview with Allagash where the brewers stated that they mash low to try to get their primary fermentation to finish as dry as possible when they're planning on adding Brett to the secondary. This lets them bottle a batch much sooner since they don't need to wait as long for the Brett to get close to terminal gravity. Their Brett beers are fantastic, so they must be doing something right.

This is not what Russian River recommends. They say the opposite (for Supplication). And I guess they also must be doing something right. 

I can't get RR up my way. Send me a bottle and I'll see if I agree with you 

I'm not saying that you shouldn't leave complex carbohydrates behind for Brett, just that you don't need to.

...Brett will happily metabolize these without needing a significant carbohydrate source...

This is the answer to the thread subject (at least for Brett).

Brett doesn't need a carbohydrate (sugar, dextrin) source to contribute flavor.

Brett needs carbs and oxygen for growth, so if you pitch a small amount in secondary it may take longer to get to the desired flavor profile. Obviously other factors play into the rate of flavor contribution, i.e. temperature, competing organisms, pH, etc. etc.

Pedio does need a carb source to produce lactic acid, but most strains can break down complex starches leftover by sacch fermentation (and even some left by Brett).

Adding 'food' (sugar, dextrin) to secondary will really just result in more alcohol from fermentation by brett.

Good points. This is why I don't like to pitch straight from dregs or a WL vial without making a starter. I'd rather pitch a bigger cell count of healthy cells. There's some old thinking out there that Brett is like the Mad Max of yeast, and you should subject it to harsh conditions to get it to thrive (i.e., low cell counts). In reality, it's like any other yeast - treat it well and it will treat your beer well.

[kylekohlmorgen]

I can't get RR up my way. Send me a bottle and I'll see if I agree with you 

ME TOO!