Controlling Brettanomyces flavours w/ brewing techniques

[unclebrazzie]

Follow-up in case anyone's interested.

I pitched in secondary with a pack of Bretts four weeks ago, which formed a nice pellicle after about a week. Room temp, which in this seasons runs between 20 and 25 C.
Four weeks after pitching, it seems like the Bretts are making short work with the butyrate: while the bileous puke smell is still present, it's gradually turning into something resembling ripe pineapple with a lot of fizz. Butyrate esters, apparently.

I'm leaving this baby to stew some more before I take a gravity reading, and a much dreaded taste.

 

[unclebrazzie]

Following up:

sampled yesterday. The Bretts have muched their way through quite a bit of the residual sugars, as well as a hefty dose of the butyrate. Whilst still decidedly reeky, it's turned more cheesy than vomity now, and the Brets are beginning to display their signature barnyard aromas.

Together with the coriander and the salt, the Brett-tempered butyrate is turning into a really weird, but interesting brew. So far, I seem to be the only one able to get past the reek, but I'm sure, with more time, the Bretts will tame this beast

 

[Spelaeus]

Following up:

sampled yesterday. The Bretts have muched their way through quite a bit of the residual sugars, as well as a hefty dose of the butyrate. Whilst still decidedly reeky, it's turned more cheesy than vomity now, and the Brets are beginning to display their signature barnyard aromas.

Together with the coriander and the salt, the Brett-tempered butyrate is turning into a really weird, but interesting brew. So far, I seem to be the only one able to get past the reek, but I'm sure, with more time, the Bretts will tame this beast

Really interesting, thanks for providing the follow-up. Good to know that there MAY be a method for rendering Clostridium infested beer drinkable.

 

[unclebrazzie]

Thx. I should really stress here that "drinkable" become a very subjective term at this stage

While I found the beer "drinkable-bordering-on-the-very-weirdly-off-putting", my wife made a very sour face when she took a sniff. The kids refer to the beer as "vomit-and-pigsty-brew" by now.

I think the smell is the major detractor from the beer's overall enjoyability by now. Sure, it's got some Brett-funk already, but as long as the butyrate doesn't get down below threshold concentration, no one in their right mind is gonna want to drink it. Even so, it's never going to be everybody's favourite beer, if anyone's at all.

 

[Sam_B]

I'm doing a very similar experiment. I did a sour mash that ended up extremely butyric and ended up pitching some brett, hoping for the best with some conversion of that nasty vomit aroma and flavor to some pleasant esters. Pitched the brett about a month ago and have not tasted the results yet. I plan to report back on that.

Process:
Mashed in as usual, reduced temp to 120F (using ice), pitched some whole grains, flushed with C02, covered, and let it sit in a hot attic for 48 hrs. The temp came down to 100F during that time. Tasted mash 36 hrs in. Medium-Strong vomit aroma. Firm sour flavor, with slight vomit in the background.
After 48 hrs, similar but perhaps slightly reduced vomit aroma, stronger sour flavor, slight vomit flavor.

Did a one hour boil, which stunk up the neighborhood and drew some deriding comments from some buddies. Chilled wort and pitched a clean ale yeast strain.

I was hoping that the boil and fermentation would drive off some of that unpleasant aroma, but after 5 days of fermentation there was still a strong vomit aroma and a perceived increase in vomit flavor.

I happened to have on hand a 1L flask of Brett B (WLP650) that I had been growing up for about 5 weeks beforehand, with the last feeding about a week before pitching. I pitched all of it and am currently hoping for the best, especially given that I've got 10 gallons of this stuff.

I'll report back on the progress. I'm interested in how long it will take to transform that butyric acid into ethyl butyrate, and how much of that conversion will actually end up taking place. It's encouraging to hear that unclebrazzie noticed a distinct difference in only 5 weeks.

 

[signpost]

This thread is awesome. Thanks for all the info, thoughts, and opinions. I'm just getting into sours and tying to understand how the stuff works. Thanks.

 

[unclebrazzie]

Update on the SpewBrew: it's been nearly three months since I pitched the Brett, and almost all the butyrate is gone. There's noticeble, but subjectively appreciable parmesan-tang to it, with lots of different weird smells surfacing from underneath that. Band-aids and something farmaceutical, pig sty and a lemony zip which somehow ties it all together. Flavour-wise it's becoming the singlemost complex/weird beer I've brewed so far, tasting like all the above and yet nothing like it. I'm leaving it in secondary until the Brett's all done, or until it looks like things are stabilising.
But even at this stage, I can verify that yes, Brett clears up butyrate and turns it into "something more palatable". It takes time, but then, it's Bretts, innit? :fro:

 

[Oldsock]

Finally wrote up an experiment I started a few months ago. Looking at the difference between the same Brett strain in a high 4VG wort (ferulic acid rest and Belgian ale) and low 4VG wort (single infusion and English ale). Results in a couple months!

http://www.themadfermentationist.com/2014/09/phenols-and-brett-fruity-and-funky.html

 

[metic]

I have a question people here might be able to help with.

From reading Chad's research, I get that brettanomyces produces a vinyl phenol reductase, which means it can convert 4-vinyl derivative into 4-ethyl derivatives. So its taking phenols from the wort, and converting them into other phenols, right?

Is there any evidence that brettanomyces can do something similar with esters? Again, from Chad's research, I get that esterases produced by brettanomyces can take fatty acids in the wort and produce new esters. But can they also take existing esters, and convert them into different ones, as happens with the phenols?

 

[Oldsock]

I have a question people here might be able to help with.

From reading Chad's research, I get that brettanomyces produces a vinyl phenol reductase, which means it can convert 4-vinyl derivative into 4-ethyl derivatives. So its taking phenols from the wort, and converting them into other phenols, right?

Is there any evidence that brettanomyces can do something similar with esters? Again, from Chad's research, I get that esterases produced by brettanomyces can take fatty acids in the wort and produce new esters. But can they also take existing esters, and convert them into different ones, as happens with the phenols?

Esters require fatty acids. Brett can hydrolyze (split) existing esters into their component alcohol and acid. So I guess it is possible that for example Brett could hydrolyze isoamyl acetate (into isoamyl alcohol and acetic acid), then create ethyl acetate (with the acetic acid plus ethanol from the beer). However with a flavor threshold of 1.6ppm the loss of the isoamyl acetate will be much more significant than the tiny gain in ethyl acetate with its 33ppm flavor threshold.

However, Brett couldn't turn something like ethyl lactate into ethyl butyrate without a source of butyric acid though.

Hope that helps!

 

[metic]

Brilliant, thanks.

 

[Sam_B]

Following up:

sampled yesterday. The Bretts have muched their way through quite a bit of the residual sugars, as well as a hefty dose of the butyrate. Whilst still decidedly reeky, it's turned more cheesy than vomity now, and the Brets are beginning to display their signature barnyard aromas.

Together with the coriander and the salt, the Brett-tempered butyrate is turning into a really weird, but interesting brew. So far, I seem to be the only one able to get past the reek, but I'm sure, with more time, the Bretts will tame this beast

Just tasted my butyric sour mash experiment. It's been about 7 weeks since pitching the brett. Definitely a big difference, although its still not something I would really enjoy drinking at this point.

For me, the aroma is about 50% butyric, with the remainder being a combination of esters (decidedly pineapple-esque) and alcohol. Flavor-wise, I get a medium sourness (acidic) with a strong bile aftertaste (my mouth kinda tastes like I puked earlier). Minimal ester flavors, no detection of cheese or characteristic barnyard brett flavors.
A buddy of mine got a mostly fruity ester aroma, with butyric just in the background.

unclebrazzie- How much brett did you pitch, and what was the variety? In retrospect, I wonder if it would have been better for me to pitch less brett, encouraging more growth and therefore ester production. I ended up pitching a 1L "starter" of Brett B (WLP650) that I had been growing up and re-feeding for about a month.

 

[Sam_B]

oops. you said WLP644. got it

 

[unclebrazzie]

oops. you said WLP644. got it

In restrospect, I realise it was Wyeast5112. One full (and fresh "bag").

Also in retrospect, I realise you are probably right in that less = more where yeast-as-a-cleanup-agent is concerned. I guess it all depends on what you want to achieve: get rid of unwanted metabolites (such as butyrate) or convert said chemicals to something more desirable (such as butyrate esters in this case).

My understanding is that, in time, Brett will clean up most carbohydrate acids. Whether it will actually recycle them into something worthwhile is another matter.

 

[FatsSchindee]

Hey all, gonna give Brett a try for the first time, and thought I'd ask your opinions...

On a recent Basic Brewing Radio podcast, James talked to a homebrewer who took a previously bottled beer that he thought was too sweet, and decanted and refermented with different Brett (and Lacto) strains. Seemed to have good results. Have any of you done this?

I have an extract Barleywine that I'm considering this with... It was my third brew ever, still didn't exactly know what I was doing, and it's a bit sweeter and not as complex as I'd have hoped. Though, it has improved somewhat in the 1.5 yrs since I brewed it, but not all that much (I try one every other month, and I'm not really excited to finish it after a few swallows... So it wouldn't be a waste if this experiment makes it worse!).

I'm thinking of using Brett Brux (White Labs), but am open to other suggestions. I have about 24 bottles (12 oz) left, so am thinking of taking most of those for a 2 gal batch (and leaving a few for comparison/further aging). I have two one-gal glass jugs I am planning on using (thinking of splitting one vial between the two without a starter... Thoughts?), and maybe adding oak chips to one of them.

My question is about oxygen - I've heard that Brett needs a little bit to do its magic. So if I'm using glass, should I just use sanitized foil over the mouth to let some O2 in, or a foam spongy stopper, or a regular airlock? Or, being that it's slightly porous to O2, should I find a two gallon bucket to use instead?

I have a couple ales up on deck for my fermentation chamber, so I'd probably throw this in with them at around 68 F (room temp at my house is usually in upper 70s, and I've heard that may be too warm and cause more undesirable flavors?), and let them go for a few months...

Any advice or feedback would be appreciated - cheers!


Sent from my iPhone using Home Brew

 

[metic]

You'll get plenty of oxygen from transferring the beer out of bottles back into a fermenter---if anything, I'd be worried about how to minimize it. I know the guy on that BBR episode didn't seem to have any problems with oxidation, but I'd still be cautious, and definitely wouldn't take any additional steps to increase exposure to oxygen.

 

[FatsSchindee]

You'll get plenty of oxygen from transferring the beer out of bottles back into a fermenter---if anything, I'd be worried about how to minimize it. I know the guy on that BBR episode didn't seem to have any problems with oxidation, but I'd still be cautious, and definitely wouldn't take any additional steps to increase exposure to oxygen.

Hmmmm... Good point. He didn't elaborate on his technique other than he "decanted carefully" (iirc). I was thinking I'd pop all the caps off, but let the bottles just sit and go flat (I'd throw a piece of foil over each opening to reduce chance of unwanted contamination) for a while (think a day would be plenty of time? Too much?). Then, I'd pour slowly and carefully down the tilted side of the jug, one by one, minimizing splashing. Any other tips?

Thanks for the response!


Sent from my iPad using Home Brew

 

[helibrewer]

Hmmmm... Good point. He didn't elaborate on his technique other than he "decanted carefully" (iirc). I was thinking I'd pop all the caps off, but let the bottles just sit and go flat (I'd throw a piece of foil over each opening to reduce chance of unwanted contamination) for a while (think a day would be plenty of time? Too much?). Then, I'd pour slowly and carefully down the tilted side of the jug, one by one, minimizing splashing. Any other tips?

Thanks for the response!


Sent from my iPad using Home Brew

If you have a CO2 tank you could use a 2-hole stopper with 1 long tube and push the beer out with very low pressure...think bottle-sized keg.

 

[youreanimpulse]

Hmmmm... Good point. He didn't elaborate on his technique other than he "decanted carefully" (iirc). I was thinking I'd pop all the caps off, but let the bottles just sit and go flat (I'd throw a piece of foil over each opening to reduce chance of unwanted contamination) for a while (think a day would be plenty of time? Too much?). Then, I'd pour slowly and carefully down the tilted side of the jug, one by one, minimizing splashing. Any other tips?

Thanks for the response!


Sent from my iPad using Home Brew

Sounds like a recipe for more oxygen (from being left out) than just carefully pouring with the CO2 still in the beer. If you have a CO2 tank you could also purge the fermenter, and trying not to splash you should be ok.

 

[Oldsock]

Brett does great in bottles with very little oxygen (think Orval). So many more beers are ruined by too much oxygen than too little. Oyxygen allows Brett to generate more energy from carbohydrates, but to produce acetic acid instead of ethanol. A little acetic acid (or the ester Brett creates from it, ethyl acetate) can be pleasant, but too much and you'll have a vinegar or nail polish remover bomb.

 

[lousbrews]

I have a question in regards to characteristics contributed by different strains when copitched with sacc. I'm currently working on sour mashing (2-3 days w/ strains of both homo/heterofermentive lax) boiling then pitching sacc with brett. (~50-50 ratio blended on pitching)

My question is do different brett strains have different characteristics in these more acidic conditions or do they simply contribute the same characteristics?

Edit
Working on sour IPA, i.e. red swingline type beer.

 

[Oldsock]

I have a question in regards to characteristics contributed by different strains when copitched with sacc. I'm currently working on sour mashing (2-3 days w/ strains of both homo/heterofermentive lax) boiling then pitching sacc with brett. (~50-50 ratio blended on pitching)

My question is do different brett strains have different characteristics in these more acidic conditions or do they simply contribute the same characteristics?

Edit
Working on sour IPA, i.e. red swingline type beer.

A lower starting pH does mute the production of some esters according to Chad Y's research. Also drinking the beer young and loaded up with hops will obscure some of the varietal Brett character. However, there will always be some differences based on strain!

 

[lousbrews]

A lower starting pH does mute the production of some esters according to Chad Y's research. Also drinking the beer young and loaded up with hops will obscure some of the varietal Brett character. However, there will always be some differences based on strain!

Thats great to hear!
I guess what I should have stated was more of what will further enhance the citrus and floral characteristics. But I am currently testing single strains to see what happens. Thanks for input as its completely welcome!

 

[Max_Chavez]

I have a question in regards to characteristics contributed by different strains when copitched with sacc. I'm currently working on sour mashing (2-3 days w/ strains of both homo/heterofermentive lax) boiling then pitching sacc with brett. (~50-50 ratio blended on pitching)

My question is do different brett strains have different characteristics in these more acidic conditions or do they simply contribute the same characteristics?

Edit
Working on sour IPA, i.e. red swingline type beer.

Hello,

Are you saying you're doing a side-by-side of two different Lax strains or using them together? I'd love to hear about it, either way.

Cheers!

 

[FatsSchindee]

Great info, guys - thanks. I'm glad I asked, because I obviously had heard wrong. I'd heard of people using oak dowels inserted into carboy caps, or using plastic buckets, both to let a little bit of O2 in during fermentation with Brett and mixed sour cultures. I'll just use a standard airlock during the refermentation in the glass jugs.

I don't have a CO2 tank, as I don't keg, but I won't leave the bottle open at all (as mentioned previously), and I'll try to minimize splashing of course. And then after the Brett finishes up, when I re-bottle I'll use some O2 caps to help minimize exposure. As far as priming goes at that point, any special tips or different procedures there, for a Brett beer?

Thanks again!


Sent from my iPhone using Home Brew

 

[lousbrews]

Hello,

Are you saying you're doing a side-by-side of two different Lax strains or using them together? I'd love to hear about it, either way.

Cheers!

They are pitched together. I have a house culture containing both although the exact growth rates I have no clue about. Its just a mix of Lacto D. and Lacto B, the idea being that Lacto B. is heterofermentive producing CO2 which is ideal for sour mashing since you want to have minimal oxygen present. The CO2 will displace the oxygen and form a more anaerobic environment ideal for Lacto D to do its thing and make the mash sour. I pitch a strong starter thats been sitting at 115F for a few days to go nuts on the sour mash.

I am more doing the side by side of brett characteristics with IPA's.

 

[finsfan]

sub'd so I remember to read the whole thread

 

[Max_Chavez]

Cool. I was planning on making a 1 gal starter of a vial of 677 plus some grains at 105 for a few days as my house culture. Any tips/experience for maintenance of the lacto culture?

My plan is to use that for both a 100% lacto berliner as well as a sour mash inocc. And do those side by side.

Thanks!

 

[lousbrews]

Cool. I was planning on making a 1 gal starter of a vial of 677 plus some grains at 105 for a few days as my house culture. Any tips/experience for maintenance of the lacto culture?

My plan is to use that for both a 100% lacto berliner as well as a sour mash inocc. And do those side by side.

Thanks!

I follow oldsocks technique of using apple juice to maintain my culture.

 

[Oldsock]

Tapped my experimental “how to phenols influence Brett” batch last weekend. Initial results were… surprising. The Belgian primary (w/ ferulic rest) batch was as expected, although not as funky as I would have hopped for nearly four months old. On the other hand the English yeast (single infusion mash) batch was a clove bomb. Seems like the Brett is slowly converting the ferulic to 4VG, putting it well behind the Belgian primary fermented batch (which was already clove-like pre-Brett).

Full tasting notes, details, discussion etc.

Luckily the guys at the MBAA meeting didn’t kill the kegs, so I’ll be able to provide updates on where they go from here!