Tips for cold crashing?

Box of Rocks

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Am planning to cold crash my next batch, but am concerned with oxidation. Considering inflating Mylar balloons with CO2 after the first 24 hours of fermentation, and maybe using a blowoff tube with a double mason jar setup, although that seems too complex. Thoughts?
 
Honestly I've largely stopped cold crashing just to remove the risk. Once it's bottled or kegged it can be cold crashed without any risk.

Now if you want to gelatin fine it, not honestly a lot you can do to avoid the issue other than drink it quick. It's not going to go bad in an afternoon.
 
I agree, too complex. Now can you tell me why you're planning to cold crash?
Good question, but I know you already know the usual reasons. For me, the benefit is a more clear beer. Also hope to try brewing a lager (or lagerPA) at some point, so there’s that.
 
Honestly I've largely stopped cold crashing just to remove the risk. Once it's bottled or kegged it can be cold crashed without any risk.

Now if you want to gelatin fine it, not honestly a lot you can do to avoid the issue other than drink it quick. It's not going to go bad in an afternoon.
Would like to make it work, but have a bucket system and wonder if it is beyond my technical capabilities to prevent too much oxidation. Is there a correlation between the time for decreasing the temp and the amount of pressure on the system? Perhaps I can find a good tradeoff between time and pressure. I’ll try whirlfloc next batch, but not quite as effective I imagine.
 
Good question, but I know you already know the usual reasons. For me, the benefit is a more clear beer. Also hope to try brewing a lager (or lagerPA) at some point, so there’s that.
^Correction - IPL, not LPA
 
So, can I assume that you are bottling?
 
I've got an old demijohn I hardly ever use. I put a few litres of sanitiser in it and a bung with two holes. One has the tubing from the fermenter, the other starts off with an airlock. When I'm down to about 10 SG points left I'll replace the airlock with a mylar balloon. I'll then crash down to about 4C for a few days.

That said, the only reason I crash these days is to experiment with cold dry hopping. I used to crash when I was dry hopping loose to stop the hop debris blocking up the keg posts and the transfer. It never really worked well enough and I've moved back to dry hopping in bags. So if I was hopping at normal temps I wouldn't bother with the crash and just bottle/transfer to the keg.

balloon.jpg
 
I've got an old demijohn I hardly ever use. I put a few litres of sanitiser in it and a bung with two holes. One has the tubing from the fermenter, the other starts off with an airlock. When I'm down to about 10 SG points left I'll replace the airlock with a mylar balloon. I'll then crash down to about 4C for a few days.

That said, the only reason I crash these days is to experiment with cold dry hopping. I used to crash when I was dry hopping loose to stop the hop debris blocking up the keg posts and the transfer. It never really worked well enough and I've moved back to dry hopping in bags. So if I was hopping at normal temps I wouldn't bother with the crash and just bottle/transfer to the keg.

View attachment 12253
Thanks, makes sense. Planning on dry hopping as well. Perhaps I should try a batch or two without crashing and see how it goes.
If I did crash, I won’t be opening to measure gravity, and have no tilt, so wonder if there is a typical timeframe for swapping to a balloon, or if that is always yeast, grain and OG dependent.
 
The way you avoid oxidation problems is to chill the beer a couple of degrees C per day. That way you can eliminate suck-back by simply refilling the airlock. I have never found a good reason to cold-crash as in thy to drop the temperature quickly as opposed to dropping it a few degrees a day and wanted to know if you had.
 
Thanks, makes sense. Planning on dry hopping as well. Perhaps I should try a batch or two without crashing and see how it goes.
If I did crash, I won’t be opening to measure gravity, and have no tilt, so wonder if there is a typical timeframe for swapping to a balloon, or if that is always yeast, grain and OG dependent.
It really doesn't suck a lot out of the balloon. So I'm guessing you'd be pretty safe waiting until you notice the main fermentation phase has finished. When the bubbles start to slow down and once the krausen starts to finish. Also that mylar balloon I've got seems to take forever to fill up, so I could probably put it on earlier if I needed to.
 
The way you avoid oxidation problems is to chill the beer a couple of degrees C per day. That way you can eliminate suck-back by simply refilling the airlock. I have never found a good reason to cold-crash as in thy to drop the temperature quickly as opposed to dropping it a few degrees a day and wanted to know if you had.
Perhaps 4F a day might be good, going from 68 to 48 over five days, starting after dry hop on day five. Less pressure on the system. (Apologies for my archaic Temp regime - I hope to shift to C at some point.)
Cold crashed the last two batches, just by wrapping the airlock with sanitized baggies, rubber bands and tape, but I bet the bucket / wrapping wasn’t completely airtight. Batches were very good, but looking for even better. Moving to a smaller batch bucket system this time, but similar overall.
Just curious - do you think 4F a day would drain an S airlock of vodka (or Starsan) with suckback? Hoping to not have to refill.
 
It really doesn't suck a lot out of the balloon. So I'm guessing you'd be pretty safe waiting until you notice the main fermentation phase has finished. When the bubbles start to slow down and once the krausen starts to finish. Also that mylar balloon I've got seems to take forever to fill up, so I could probably put it on earlier if I needed to.
Just curious - do you rinse the inside of the balloon with sanitizer prior to first use, do you reuse it?
 
OOps! Reading this set of post reminds me I goofed last night. I do cold crash. I just put a 1 quart zip lock bag taped on the end of the blow off tube filled with CO2 . Last night I walked past the fermentation fridge and dropped the temp to 34°F and walked away, forgot to bag it.
I guess I'll just give it a quick purge wit a bit of CO2 and bag it and hope for the best.
 
OOps! Reading this set of post reminds me I goofed last night. I do cold crash. I just put a 1 quart zip lock bag taped on the end of the blow off tube filled with CO2 . Last night I walked past the fermentation fridge and dropped the temp to 34°F and walked away, forgot to bag it.
I guess I'll just give it a quick purge wit a bit of CO2 and bag it and hope for the best.
Unfortunately I don’t have the CO2 tank setup yet for purging, carbonating, but someday...
 
Just curious - do you rinse the inside of the balloon with sanitizer prior to first use, do you reuse it?
I reuse and haven't rinsed the inside. I'm hoping the sanitiser inside the demijohn provides the protection needed.
 
Now that I have reclaimed my chest freezer for use as a fermentation chamber I have returned to cold crashing most of my beers. I bottle and without cold-crashing I'm more likely to have bits of yeast & hop debris floating in my glass. Not much but definitely undesirable. Before cold crashing I reattach the blow-off hose and put the open end on the bottom of the chest freezer. To get CO2 into the blow-off hose I fill it with sanitizer and place it on the bottom of the chest freezer. As the sanitizer pours out, mostly CO2 (I hope) is drawn in. I then remove the airlock and attach the blow-off hose. I'm not sure how effective it is and will someday try either the mylar balloon or the double mason jar techniques.
 
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Now that I have reclaimed my chest freezer for use as a fermentation chamber I have returned to cold crashing most of my beers. I bottle and without cold-crashing I'm more likely to have bits of yeast & hop debris floating in my glass. Not much but definitely undesirable. Before cold crashing I reattach the blow-off hose and put the open end on the bottom of the chest freezer. To get CO2 into the blow-off hose I fill it with sanitizer and place it on the bottom of the chest freezer. As the sanitizer pours out, mostly (I hope) is drawn in. I then remove the airlock and attach the blow-off hose. I'm not sure how effective it is and will someday try either the mylar balloon or the double mason jar techniques.
Barbarian - curious about your setup. I assume the hose goes into a jug, and that the length is enough to capture sufficient CO2, or does the jug capture the gas?
Wondering if a capped jar of sufficient size would be able to hold the same amount of CO2 as a balloon. Smaller volume but under higher pressure.
 
I cold crash every beer it's part of my brew process best way I mitigate o2 ingress from cold crash is fermenting under pressure;).
I dont bag any hops in my system all set free loose any bubble fermentor will be your friend.
 

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