Vomit\Rotten Cheese smell from Berliner Weisse

[jaylakejr]

About a month ago I did a no boil Berliner Weisse. I pitched lacto on it and let it rock and roll. About 4 weeks later I came back and tossed some dry yeast on it.... I think it was s33. Anyway. About a week later I went to grab a sample and MY GOD does it stink. I nabbed a sample and there was crap floating in it and there is a gross sludge on the surface. I couldn't even bring myself to drink it, it smelled that bad. Question is, WTF should I do? Dump it? Let it ride a little longer? I heard pitching some Brett might help. Anyone else have this issue? I would love to hear about any experience with this gross stink.

 

[Oldsock]

Sounds like butyric acid. Brett can change it into a great tropical fruity ester, but it'll probably leave enough behind to be annoying. I'd probably dump and start over, but if you don't need the carboy, you could pitch a bunch of strains and let it ride.

 

[jaylakejr]

Dang... that's what I was afraid of. Thanks for the response. BTW great blog, aside from this site your blog is on my frequently visited beer sites.

 

[sweetcell]

4 weeks was probably too long. most folks seem to get the souring they need in 2 to 4 days.

during the lacto-only fermentation, you need to protect the beer from O2. popular thing to do is to purge the vessel with a heavy gas (CO2, some get all fancy and use a noble gab like argon) and keep it sealed while the lacto does it's thing.

 

[ne0t0ky0]

I had some butyric in my BW; I aged them on fruit for about 4 months with Brett B; that cleaned up the majority of the cheese; if you know what it smells like, then you can still pick it up, but it's certainly not so strong now that folks don't want to drink it.

 

[Weezy]

What causes it (i.e. The butyric acid production)? What can you do to avoid it? I had a hint of it on a sour stout.

 

[ne0t0ky0]

Some bacteria, including lacto can produce it... not entirely sure what exact conditions produce it. In my first BW, I used a pure lacto strain and I didn't get any. The second brew, I ended up having to pitch some grains since I let me wort get too hot and killed off the pure lacto. This second brew picked up quite a bit of butyric, I aged most of it out on brett.

 

[Bsquared]

What causes it (i.e. The butyric acid production)? What can you do to avoid it? I had a hint of it on a sour stout.

Butyric acid is a by product of anaerobic fermentation typically bacterial, Brettanomyces will convert this to ethyl butyrate, which is a very similar aroma to pineapple/tropical fruit.

 

[Oldsock]

Butyric acid is a by product of anaerobic fermentation typically bacterial, Brettanomyces will convert this to ethyl butyrate, which is a very similar aroma to pineapple/tropical fruit.

Interesting note. Anecdotally it seems to be a much bigger issue under aerobic conditions, say a poorly sealed mash tun during a sour mash. Maybe that flavor is actually another compound? Despite the fact that it is only the produced of obligate anaerobes, it is found in kombucha (which is usually exposed to air during fermentation).

 

[ne0t0ky0]

Maybe that flavor is actually another compound? Despite the fact that it is only the produced of obligate anaerobes, it is found in kombucha (which is usually exposed to air during fermentation).

That is interesting; I don't ever get that smell,aroma from my kombucha either. I don't yet have a microscope, but I'm definitely interested to see what sort of bugs and yeast are in kombucha versus a sour beer.

When I did get butyric in my BW, I would say it was exposed to more O2 than normal. I had been stirring the wort to ensure a uniform heat distribution; this of course introduced more O2 than my first attempt in which I set-it-and-forgot-it for 3 days.

And just recently, I let extra wort from my mash just sit in a closed HDPE bucket for a week on two occasions. Both had soured significantly (pH of 3.6) but zero butyric.

 

[Calder]

When using grans, you have a number of different 'bugs'. Clostridium produces butyric acid in the presence of O2, it has nothing to do with the lactic bacteria.

 

[Oldsock]

When using grans, you have a number of different 'bugs'. Clostridium produces butyric acid in the presence of O2, it has nothing to do with the lactic bacteria.

The issue is that I can't find a source that says Clostridium is aerobic, everything I see say anaerobic. However, we're left with the anecdotal observations that oxygen increases butyric production.

 

[Bsquared]

The issue is that I can't find a source that says Clostridium is aerobic, everything I see say anaerobic. However, we're left with the anecdotal observations that oxygen increases butyric production.

Clostridium is an obligate fermenter, meaning it requires O2 to perform fermentation. Interestingly this link states,

Clostridia are rod-shaped, but when producing spores they appear more like drumsticks with a bulge at one end. Most clostridia are obligate fermenters. They ferment by pathways that generate organic solvents such as butanol.

Butanol can then be reduced to form Butyric acid.

From what I have read, Clostridium is an anaerobic gram positive bacteria, but is an obligate fermenter, meaning that if O2 is present it can use a fermentation metabolic pathway, but if no O2 is present it will use an anaerobic pathway

Growth conditions:

Temperature range: 3-48°C (38-118°F)
Type A and B: 10-50ºC (50-122ºF)
Type E: 3-45ºC (38-113ºF)
Optimum Temperature for toxin development: 35°C (95°F)
pH range: 4.6 - 8.9

 

[masonsjax]

I had a grain induced sour mash that stunk up the basement with bile smells when boiling, but after fermenting on pacman and carbonating in the keg, there's only a tiny trace of that aroma left. Some friends were over and loved it, even took growlers home, but my SWMBO can't get over it. I think it's subdued enough to not be in the way. I cover my sour mashes with plastic wrap and flood with club soda, definitely low amount of O2 in there.

 

[Oldsock]

Clostridium is an obligate fermenter, meaning it requires O2 to perform fermentation. Interestingly this link states,

Butanol can then be reduced to form Butyric acid.

From what I have read, Clostridium is an anaerobic gram positive bacteria, but is an obligate fermenter, meaning that if O2 is present it can use a fermentation metabolic pathway, but if no O2 is present it will use an anaerobic pathway

I thought obligate fermenter means that it can only ferment, it cannot respire? As opposed to facultative anaerobe (like brewer's yeast), which can produce more energy when oxygen is available.

However, your link does mention that some strains are microaerophilic, meaning they prefer oxygen (just in concentrations below atmospheric).

 

[Bsquared]

I thought obligate fermenter means that it can only ferment, it cannot respire? As opposed to facultative anaerobe (like brewer's yeast), which can produce more energy when oxygen is available.

However, your link does mention that some strains are microaerophilic, meaning they prefer oxygen (just in concentrations below atmospheric).

Yes, you are correct about that, thanks for catching that, obligate fermenters can only produce ATP through a fermentation pathway, I must have miss read or inferred that part about O2 requirement, I think what that link states is it has a tolerance for O2 but no genes encoding enzymes for the (tricarboxylic acid cycle) TCA cycle, or respiration.

I think the thing is here that there are a lot of unknowns and variables here regarding what organisms are present and which are doing what. And much like there are lots of strains of yeast that and or can not perform different catabolic pathways the same is true for the different strains of bacteria, and in a sour mash where you inoculate with a hand full of grains, you will have an unique ecosystem of yeast, molds, and bacteria all its own that develops.

 

[unclebrazzie]

Piggy-backing this thread.

I'm brewing a gose, with wort soured both by acidulated malt and pitching it (pre-boil) with a bottle of geuze.

36 hours later at about 30°C, it reeked of yoghurt-trying-to-be-cheese-whilst-puking-all-over-the-fridge. Butyric acid, yeah.

Boiled it anyway, much to the chagrin of my wife, kids, cats and guinea pigs. The whole house still reeks of it.

The wort itself, even pre-boil, whilst decidedly stinly, actually tasted okay-ish. After boiling (which I assume not only killed the bugs responsible but also evaporated much of the stink out of the wort and into my house, it was actually pretty yummy. Yummy enough to pitch and hope for the best, if not the very worst.

Contemplating pitching Bretts to scavenge all the off-flavours and transform them -by the virtue of being Bretts- into something tasty.

If anyone has any advice on this brew, please post in the recipe thread I linked to. Tangentials on vomit and stink can go here, I suppose.

 

[wingedcoyote]

I had a grain induced sour mash that stunk up the basement with bile smells when boiling, but after fermenting on pacman and carbonating in the keg, there's only a tiny trace of that aroma left. Some friends were over and loved it, even took growlers home, but my SWMBO can't get over it. I think it's subdued enough to not be in the way. I cover my sour mashes with plastic wrap and flood with club soda, definitely low amount of O2 in there.

I'm interested in your club soda purging technique -- never heard that one before, and it sounds pretty handy for non-keggers like myself. Any details?

 

[masonsjax]

I read about it in some thread here on HBT. It made sense to me so that's how I do it now. I smooth the air bubbles out of the plastic wrap on the surface, then float a little bit of club soda on top before closing up the lid. The theory is that it will leave a little blanket of co2 on top to further protect the sour mash. I don't think it can hurt at least.

 

[wingedcoyote]

Sounds good, I'll give it a shot. Thanks!

 

[unclebrazzie]

Here to confirm that yes: Bretts do have the ability to convert butyrate to its esters, and hence vomit smells to more pleasing pineapple aromas. Takes time, but then again all good things do.