You will definitely be getting some oxidation. There have been a number of threads around here on how people use a balloon on the airlock to collect CO2 during fermentation and then this will resupply the headspace during cooling instead of drawing in air.
It’s only necesary if you think it is. For some it’s more important than others
Now I get it. Thanks @Robert! That’s the part I was missing.
Why bother? If you’re kegging an ale, and particularly if it’s a dry hopped ale, then you want to get on it ASAP.
If I could be said to cold crash then I cold crash in the keggerator, and it’s ready to drink after 2 or 3 days. I have noticed no ill effects from this procedure in 11 years of all-grain brewing.
Charlie (doesn’t make lager)
It’s probably not worth the effort but, but it’s a fascinating idea. I think I’m going to give it a try and see if it makes a difference.
It really is very little effort once you have the equipment fabricated. I put a balloon in place today in only a couple of minutes, including sanitizing the stainless feed tube. I bottle all my beer and don’t keg, so I don’t have any CO2 tanks around. The only CO2 I have is the stuff I make during fermentation, so I take a bit of care to capture it and re-use it.
late to the conversation here but a couple thoughts that i don’t see brought up yet:
-one reason to keep the crash a bit more gradual is to save the compressor of your chest freezer (if that’s how you’re doing it). if i try to chill 10 gallons in one go i’ll definitely kill my freezer, so i go about 5 deg C at a time.
-personally i don’t get clear beer until a couple weeks of cold crashing.
-now that i’m reading all this input about oxidation i might stop cold crashing in the carboys and just do it in my kegs.