I have a question about the role of oxygen in lambic fermentation. Like most homebrewers, I use a glass carboy. In your experience when making a Lambic, do you find that using an airlock produces a better result than just using some tinfoil? I figure that barrels create much more oxidation than an airlocked carboy would provide, but I'm not quite sure what the best choice is.
Lambic - to airlock or tinfoil?
- Thread starter jibby
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I found that the exposure to O2 was good for developing Brett flavors and sourness in the secondary fermentation of my sour beers so far. I used foil once, but it dose not keep fruit flies out well and will lead to an acitobacter infection.
if you can try rigging up a stopper with an air filter on it so nothing can sneak in to your beer.
if you can try rigging up a stopper with an air filter on it so nothing can sneak in to your beer.
tasq
Well-Known Member
My beers sour and get funky just fine with an airlock.
RJSkypala
Well-Known Member
agreed. given I have only brewed about 4 sour beers thus far, I wouldn't put foil on my carboy and risk the acetobacter and fruit flies.
Sure its going to sour with out exposure to O2 in the air, but traditionally these beers are stored in wood that has a level of permeability to the atmosphere that helps to develop a more complex beer.
RJSkypala
Well-Known Member
I would hesitate to make a positive correlation between O2 exposure and complexity. O2 is only one of the many factors in the complexity in flavor that comes through long-aging in a barrel. Under homebrewing conditions we need to consider how to keep these various factors in balance as the materiality of it is just not the same.
I would stay on the side of caution and let my beer age with an airlock for an extender period of time. If enough sourness doesn't develop with time then I would consider different ways of cautiously introducing oxygen.
I would stay on the side of caution and let my beer age with an airlock for an extender period of time. If enough sourness doesn't develop with time then I would consider different ways of cautiously introducing oxygen.
ryane
Well-Known Member
the small amounts of 02 that get in are more than enough to make a fine beer, personally I try to minimize the exposure to oxygen, vinegar is nasty, and worse ethyl acetate aka nail polish remover can be produced when brett is exposed to 02
From what I understood was that the amount of Acidic acid produced by Brett is minimal even in the presence of O2, most souring comes from Lacto and pediococcus. High levels of acidic acid indicates that acetobacter is present. Also the pellicle layer formed by Brett acts as an O2 barrier as well as protecting the beer from Acetobacter.
From what I have read, Pediococcus will do the majority of the souring for lambic's by producing Lactic but can produce a lot of diacetyl at the same time too. O2 inhibits pedio's growth, so a good balance of O2 in the system will get you a good sour with minimal diacetyl. though with time the brett will clean up the diacetyl, but that can take a long time, at least from my experience.
RJSky, I agree that under the home brewing conditions we need to consider the size of our batches and the limitations of our equipment, but we also need to strive to create a similar environment to how these beers where made. Lambics and other sour beers are a product of a complex interaction between several different micro organisms all influencing eachother over the life of the beer.
Steve Piatz gave a good talk at NHC 2010that gives a good schematic of these interactions.
From what I have read, Pediococcus will do the majority of the souring for lambic's by producing Lactic but can produce a lot of diacetyl at the same time too. O2 inhibits pedio's growth, so a good balance of O2 in the system will get you a good sour with minimal diacetyl. though with time the brett will clean up the diacetyl, but that can take a long time, at least from my experience.
RJSky, I agree that under the home brewing conditions we need to consider the size of our batches and the limitations of our equipment, but we also need to strive to create a similar environment to how these beers where made. Lambics and other sour beers are a product of a complex interaction between several different micro organisms all influencing eachother over the life of the beer.
Steve Piatz gave a good talk at NHC 2010that gives a good schematic of these interactions.
You won't get an acetobacter contamination with foil, most likely you already have one if using a lambic culture. The acetobacter is an aerobic acid producing bacterium. Thus it needs oxygen. Pediococcus and Lactobacillus are microaerobic or damn near anerobic. So As Bsquared said more oxygen will lead to more acetic acid production. By minimizing the oxygen you get a softer lactic acid produced by the other souring bacteria.
this is a good point, that depends on what you pitched you may not know what you might have in there, but my concern with foil is still the fruit flies. I've seen them get in to places I thought where completely sealed off, and lost a 9 month old sour to them...I really don't like fruit flies
The Wyeast and White Labs blends don't have acetobacter, and most lambics don't either. The acetic acid is produced by bugs like pedio in the presence of oxygen... so whether or not fruit flies get in, foiling is going to lead to a fairly strong acetic character.
You want to keep oxygen exposure in lambic fairly minimal actually... it's not supposed to have much acetic character at all... it's certainly not a Flanders Red.
You want to keep oxygen exposure in lambic fairly minimal actually... it's not supposed to have much acetic character at all... it's certainly not a Flanders Red.
maskednegator
Well-Known Member
Comparing the oxygen permeability of a wooden barrel to the oxygen permeability of a carboy covered with aluminum foil is ludicrous.
maskednegator said:
I agree, they're not even close to equal. Although I'm not sure which thing YOU think lets in more oxygen, an unsealed carboy will have significantly more oxygen exposure... and by significantly, I mean about several orders of magnitude.
Pediococcus is a lactic acid bacteria.It produces lactic acid.
http://www.wyeastlab.com/hb_yeaststrain_detail.cfm?ID=149
Acetic acid is predominantly produced from Acetobacter. Brett will produce Acidic acid in the presence of O2 but in low levels.
http://www.wyeastlab.com/hb_yeaststrain_detail.cfm?ID=149
Acetic acid is predominantly produced from Acetobacter. Brett will produce Acidic acid in the presence of O2 but in low levels.
Bsquared said:
Pedicoccus produces both lactic acid AND acetic acid, actually. And the presence of oxygen determines which. Acetic acid is produced aerobically, while lactic acid is a result of anaerobic fermentation.
If you can show me this that would be great, I have looked all over trying to find that. From my readings O2 inhibits Pediococcus growth, it is a anaerobic gram positive bacteria.
http://genome.jgi-psf.org/pedpe/pedpe.home.html
ryane
Well-Known Member
acetic acid aside brett can produce really nasty compounds like ethyl acetate when exposed to oxygen, about 1.5yrs ago I had a red that was coming along wonderfully go bad in 10days when exposed to oxygen (airlock went dry) I had tasted it and was getting ready to bottle, bottling day showed up and became drain pour day
Barrels have dense microbial growth all around the wood which forms a very effective barrier to oxygen in addition to the wood, in the end you can go whatever route you want, but in my experience over the past few years (and i started by letting 02 get in) is that you really want to minimize the amount of O2 getting to these beers
brett can produce really nasty compounds like ethyl acetate when exposed to oxygen, about 1.5yrs ago I had a red that was coming along wonderfully go bad in 10days when exposed to oxygen (airlock went dry) I had tasted it and was getting ready to bottle, bottling day showed up and became drain pour dayBarrels have dense microbial growth all around the wood which forms a very effective barrier to oxygen in addition to the wood, in the end you can go whatever route you want, but in my experience over the past few years (and i started by letting 02 get in) is that you really want to minimize the amount of O2 getting to these beers
ryane
Well-Known Member
Bsquared - Everything Ive read has said that the WY/WL strain of pedio is pediococcus cerevisae Im not 100% but Id bet it could be fairly different from pedio pentosaceus which is a common cheese acid producing strain
Commercial wooden barrels let in very little O2. They are also very large, and the surface area to volume ratio is very small. But ...... they do let in more O2 than a glass carboy with a rubber bung and airlock.
If you want to simulate the O2 that gets into a barrel, take a 3 foot length of tubing, push one end over the stem in the airlock, and the other end in a jar of sanitized liquid. Just like a simple blow-off. The O2 that permeates through the walls of the tube should be close to what you might get through a barrel.
If you want to simulate the O2 that gets into a barrel, take a 3 foot length of tubing, push one end over the stem in the airlock, and the other end in a jar of sanitized liquid. Just like a simple blow-off. The O2 that permeates through the walls of the tube should be close to what you might get through a barrel.
yes this is correct that cerevisae is the strain is the common one used in brewing, but they are the same species of pediococcus, my point being they are gram positive (they have a poly-glycan cell wall and can absorb Gram dye), and that they are facultatively anaerobic as a species, meaning they don't use O2 for their metabolism.O2 is actually toxic for them and inhibits their growth.
Lambics are a deceptively complicated, there is a lot going on that is not really understood, but there is a lot of information about the major microbes that contribute to the fermentation of these beers.It's probably not too important to know exactly what they are all doing, but the more you know the better you can make decisions about your process.
For the OP This is a great power point from Vinny at RR from the Babble belt he has a good sections for things for the homebrewer to consider for brewing lambics.
As well the Babble belt has been a great resource for me to better understand who these beer are made.
Sorry for getting off topic.
