Cold crashing and oxidation

[Ozwald]

Yes. You could move the fermenter ahead of time to give it plenty of settling time, or you could rig your existing area to be able to transfer right there. If you're in a chest freezer or something like that, just be careful & don't move them too far - use a brew hauler to lift them straight up onto a shelf or something like that, they'll settle back out pretty quickly. It's not the end of the world if you transfer a little bit over, just do a 2nd closed transfer after you crash the keg.

[brewinhard]

If plastic wrap was used tightly covering the carboy mouth for cold crashing in lieu of an s-shaped airlock (which apparently allows oxygen to ingress and can lead to oxidation as the beer chills down and internal pressures reverse), then isn't plastic wrap gas permeable too or would it just happen more slowly which would be negligible in a 48 hr cold crash keeping in mind that there is still a small CO2 barrier above the beer itself?

Just trying to figure out the most optimal way to still cold crash in a carboy before kegging that introduces the least chances of oxidation. Maybe an even better way would be to first cover the carboy with plastic wrap tightly, then cover that tightly with aluminum foil and a tight rubberband as aluminum definitely does not allow gases to pass through. With all of this going on, I have been using an s-shaped airlock for cold crashing for years and have not observed any immediate oxidation in beers packaged with this process. Just constantly trying to improve wherever and whenever.

Any thoughts on this from the BN?

[Mike D]

-For me it's mostly a Dry Hop thing. Whole cones seem to take forever to fall to the bottom, they just float around. Everyone says not to dry hop for too long, so the cold crash for me is mostly to help drop down the Hops. I use a hop screen on my racking cane, and that work well. I will try to rack warm next time before I cold crash and see how goes.

[Kbar]

If plastic wrap was used tightly covering the carboy mouth for cold crashing in lieu of an s-shaped airlock (which apparently allows oxygen to ingress and can lead to oxidation as the beer chills down and internal pressures reverse), then isn't plastic wrap gas permeable too or would it just happen more slowly which would be negligible in a 48 hr cold crash keeping in mind that there is still a small CO2 barrier above the beer itself?

Just trying to figure out the most optimal way to still cold crash in a carboy before kegging that introduces the least chances of oxidation. Maybe an even better way would be to first cover the carboy with plastic wrap tightly, then cover that tightly with aluminum foil and a tight rubberband as aluminum definitely does not allow gases to pass through. With all of this going on, I have been using an s-shaped airlock for cold crashing for years and have not observed any immediate oxidation in beers packaged with this process. Just constantly trying to improve wherever and whenever.

Any thoughts on this from the BN?

Optimal - use a cask breather or low pressure regulator (<<1psi) CO2 feed into the fermenter (replace head space due pressure drop due to temperature drop). I would assume this is performed at the breweries as well.

[gwk453]

-For me it's mostly a Dry Hop thing. Whole cones seem to take forever to fall to the bottom, they just float around. Everyone says not to dry hop for too long, so the cold crash for me is mostly to help drop down the Hops. I use a hop screen on my racking cane, and that work well. I will try to rack warm next time before I cold crash and see how goes.

For whole hop dry hopping it is more efficient for the home brewer to grind the hops just prior to hopping. They then settle out just like pellet hops. The plus side is that your fermenter trub loss is less, more finished beer to keg or bottle.

[brewinhard]

If plastic wrap was used tightly covering the carboy mouth for cold crashing in lieu of an s-shaped airlock (which apparently allows oxygen to ingress and can lead to oxidation as the beer chills down and internal pressures reverse), then isn't plastic wrap gas permeable too or would it just happen more slowly which would be negligible in a 48 hr cold crash keeping in mind that there is still a small CO2 barrier above the beer itself?

Just trying to figure out the most optimal way to still cold crash in a carboy before kegging that introduces the least chances of oxidation. Maybe an even better way would be to first cover the carboy with plastic wrap tightly, then cover that tightly with aluminum foil and a tight rubberband as aluminum definitely does not allow gases to pass through. With all of this going on, I have been using an s-shaped airlock for cold crashing for years and have not observed any immediate oxidation in beers packaged with this process. Just constantly trying to improve wherever and whenever.

Any thoughts on this from the BN?

Optimal - use a cask breather or low pressure regulator (<<1psi) CO2 feed into the fermenter (replace head space due pressure drop due to temperature drop). I would assume this is performed at the breweries as well.

For sure, but without purchasing further equipment and tinkering around with setting up CO2 tank to properly regulate the pressure drop, what would be the best way around this?

Maybe an S-shaped airlock lowly filled with starsan wrapped with plastic wrap (or foil) and rubberband?

[brewinhard]

Totally perseverating on this one.... Holy OCD!
So...

Those of you who simply wrap sanitized foil with a rubberband around the carboy mouth, don't you think oxygen will ingress into the headspace?

Those of you who wrap plastic wrap with a rubberband around the carboy mouth, don't you think that gases like oxygen can diffuse and permeate right through the plastic?

Or is it such a negligible amount of oxygen over the couple day cold crash that it really isn't a big deal?

Someone? Anyone? I am totally going to lose sleep over this! Ha! just kidding, I will be too drunk to care tonight....

[BDawg]

I think even if air is sucked back in to the fermenter during crashing, it's still lighter than CO2 so oxidation really isn't a problem.