Where do you draw the line when dealing with oxygen?

[lucianthorr]

This is sort of a general question but I put it here in the wild/lambic forum because I'm more focused on beers that are sitting in fermenters for months rather than just a few weeks.

The whole topic of minimizing oxygen exposure has developed into a ridiculous phobia for me. I understand that we shouldn't be keeping our fermenter sealed but how much do we need to worry about oxygen exposure from periodic suck-back caused from temperature fluctuation over months of aging or the occasional sampling?

I'm also curious to hear how some of the wild/sour homebrewers here deal with it when you've got multiple ferments going at a time.

As always, thanks in advance.

 

[RPh_Guy]

Brett scavenges oxygen, so oxidation isn't much of a concern, and in fact Brett prefers tiny amounts of oxygen. Pellicle formation further serves as a barrier (probably).

I use silicone waterless airlocks that eliminate oxygen diffusion and suckback.

Why are your beers sitting for months?

 

[lucianthorr]

Maybe I'm doing it wrong. I do a lot of brett beers, which I always let sit in the fermenter for about 3 months before kegging. I always hear that it takes about that long for them to really contribute any character and so I figured that was the way to go.

I've kegged earlier and just burped the keg once a week but I didn't really see anything wrong with letting the beer sit. This is definitely why I asked though. I'd like to improve my process's efficiency on the cold side of things because I'm guessing it's pretty convoluted at this point.

 

[RPh_Guy]

Ok that makes sense! From your first post I didn't get the impression you were using Brett.

Don't worry too much about oxidation. I assume you can purge headspace with CO2.
Worst case scenario: The beer will develop a vinegar (acetic acid) taste if there is too much oxygen, so you'll know.
Too LITTLE oxygen can leave a mixed fermentation beer lifeless, so there's no reason to go overboard about preventing O2 exposure.

Unless you're doing 100% Brett fermentation or something similar, it needs time to do its thing.
I'd suggest reaching a stable gravity (same reading a few weeks apart) before packaging.

Hope this helps, cheers

 

[pursuit0fhoppiness]

What RPh Guy said (he's a smart guy!)

Brett is a great oxygen scavenger so you don't need to worry about oxidation too much, but you'll know too much was getting in if the beer takes on a vinegar character (when Brett consumes oxygen it creates acetic acid; if too much is being created it'll be noticeable as vinegary). RDWHAHB!