What would you do?

beer1965

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Ok so I'm sorry - this has been discussed to death, I get that. But I'm not sure what to do after reading what I've read on this..

I'll be bottling this week a very hoppy IPA with lots of dry hops. I want to cold crash to get the hops to settle. I don't have a keg system yet but thing that's next, so that's not an option. I have everything in a carboy, will cold crash and then move that into a bottling bucket. I know eventually I need to get rid of the bottling bucket step to minimize the chance of oxidization. But for now - how am I going to cold crash without having stuff from my blowback bottle sucked into the carboy? I just read about bottling bladders - looks like a good idea but too late for that on this brew.

So what would you do if you were me? Thanks guys..
 
Use a double bubble airlock while cold crashing. Fill a plastic bag with CO2 and tape the tube to the bag. If you don't have anything else then leave the tube open or stick it in a similar beer while cold crashing. Get creative.
 
Or just pull the airlock blow off tube whatever it is and cover with alfoil until cold crash temp is reached or above.
 
following up with 4Bentleys advice; if you don't have CO2 available; you can pull the blowoff tube from the blowoff bottle and cover the end with a paper coffee filter and use rubber bands to cover the end of the tube with the filter. since the blowoff tube should theoretically be full of CO2 from the fermentation process, whatever gets pulled back into the fermenter while coldcrashing should only be CO2... the filter just avoids anything that may be in the air from entering the tube... in case the tube volume is less than the volume of change due to the temperature change.
 
Probably past the point where this would help for this batch, but I use a blow off tube and airlock/balloon for my fermentations. The balloon was the cheapest helium balloon I could find. I've seen people use large orange juice bottles instead of the thing I have. Punch holes in the lid for the airlock/balloon and the blow off tube from the fermenter. Use the airlock for most of the fermentation and changeover to the balloon near the end. The cold crash doesn't end up sucking back that much gas so that balloon is easily big enough.

IMG_20200418_102939.jpg
 
I have always used a 3 piece airlock, it pulls air back in when crashing. Theoretically, any oxygen that gets in will stay at the top of the fermenter. I haven't had an oxidized beer to date (40 batches).
Screenshot_20200505-222354_Chrome.jpg
 
Even though CO2 is heavier than O2 it won't stop the O2 diffusing throughout the fermenter. You need a really heavy gas for the layering to provide protection once you start introducing new gases. And even a really heavy gas will struggle if there are any changes in temperature or movement.

As to whether the O2 that comes in when you're cold crashing makes a noticeable difference at home brew scales and timeframes, o_O
 
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I have always used a 3 piece airlock, it pulls air back in when crashing. Theoretically, any oxygen that gets in will stay at the top of the fermenter. I haven't had an oxidized beer to date (40 batches).
View attachment 9930
These are what I've used only time I've had issues at cold crashing is it froze the lid just sucked way in.
 
Thanks for all the replies. I don't have any CO2 in the house. I also can't use a 3 piece airlock as my bar fridge isn't tall enough with the carboy in it as the compressor takes up space in the bottom. I like the balloon idea and will use that on my next batch. I think for this one I'll rinse the bottom of the hose with starsan and put it into a freshly opened beer. I don't have any hoppy ipas to use. But I'll find something neutral. I'll mark the volume and that will give me a sense too of how much if any has been sucked in. Let's see! Thanks.. I really think I should start to keg but dont' know if I want to go and start getting all that stuff .. would mean a second fridge in addition to the kegging equipment.. we'll see..
 
Do a search. I've also seen where people use a really long blow off tube with the end in star san or spirit, but long enough to take care of the suck back. Hope that makes sense.
 
Do a search. I've also seen where people use a really long blow off tube with the end in star san or spirit, but long enough to take care of the suck back. Hope that makes sense.
A larger diameter blow off hose, and a very shallow amount of starsan may prevent a vacuum from forming...
 
Even though CO2 is heavier than O2 it won't stop the O2 diffusing throughout the fermenter. You need a really heavy gas for the layering to provide protection once you start introducing new gases. And even a really heavy gas will struggle if there are any changes in temperature or movement.

As to whether the O2 that comes in when you're cold crashing makes a noticeable difference at home brew scales and timeframes, o_O
Gas laws: Unless you're talking radon and a completely unoccupied basement, layering just won't happen. Gasses mix too easily. Get the air out during fermentation and keep it out with an effective airlock or positive CO2 pressure. One of the issues with cold crashing is the beer contracts, sucks the sanitizer out of the airlock then your beer is exposed to air. Yet another reason to secondary in the keg or to avoid the cold crash. The gunk will settle out of the beer at room temperature, it'll just take longer.

When I transfer, I always flush the receiving vessel with CO2. When a lighter won't burn at the upper rim, I consider the vessel flushed. The amount of oxygen cold-crashing sucks into the vessel is small and is highly diluted with the CO2 in the vessel, not much will diffuse out through the very small opening the airlock presents so top up the airlock as soon as possible with whatever you use to fill it (pro tip: Distilled water is sanitary and will not affect the flavor of the beer at all - use it in the airlock when cold-crashing to avoid sucking sanitizer solution into your beer). We really can't do "no-DO" but we can keep dissolved oxygen low if we take reasonable precautions.
 
Gas laws: Unless you're talking radon and a completely unoccupied basement, layering just won't happen...

The resource I was looking at talked about bromine being able to do it in very controlled circumstances. Though once you start talking about things like bromine, oxidation is the least of your problems.
 
Like with everything else with home brewing, you make do with what you have at the moment. When I originally started to cold crash I just put the carboy, air lock and all, into the basement fridge. Then I got a small chest freezer and fermented and cold crashed in that. When cold crashing I would hook up a blow-off tube and let the end sit on the bottom of the compartment where there was lots of CO2. Very similar to Mark's mylar balloon CO2 capture idea. Currently, as my wife has commandeered my chest freezer for storing pandemic supplies, I don't cold crash at all.
 
The resource I was looking at talked about bromine being able to do it in very controlled circumstances. Though once you start talking about things like bromine, oxidation is the least of your problems.
Not sure if it's linked to this...
I used to work with a schedule 7 gas Methyl bromide we use it for fumigation of certain food products as well as for bio security making sure certain bugs don't make it into our country at our ports in container ect.
Any Who that gas is deadly stuff kill you in 40 seconds type stuff (in a confined space which is where it's used).
Its a lazy gas if it's cold but at warmish temps dissipates redily into the atmosphere.
I remember my instructor telling me when I was doing my course saying the best PPE for this chemical is work with it Naked that way it can't settle in your boots or pockets ect ECT if there is a leak in the line lol:p!
Any Who that my expierence with gasses
 
Not sure if it's linked to this...
I used to work with a schedule 7 gas Methyl bromide we use it for fumigation of certain food products as well as for bio security making sure certain bugs don't make it into our country at our ports in container ect.
Any Who that gas is deadly stuff kill you in 40 seconds type stuff (in a confined space which is where it's used).
Its a lazy gas if it's cold but at warmish temps dissipates redily into the atmosphere.
I remember my instructor telling me when I was doing my course saying the best PPE for this chemical is work with it Naked that way it can't settle in your boots or pockets ect ECT if there is a leak in the line lol:p!
Any Who that my expierence with gasses
I'd assumed it was evil. Didn't quite understand how evil.
 
I'd assumed it was evil. Didn't quite understand how evil.
It's my understanding this is stretching my memory but it's naturally occurring in barrasicas cabbages cauliflowers ect.
Yeah 24hrs we used to fumigate for nothing survives after that lol.
 
The resource I was looking at talked about bromine being able to do it in very controlled circumstances. Though once you start talking about things like bromine, oxidation is the least of your problems.
Radon was the extreme example but yes, I'd imagine bromine could stratify, under proper conditions. Point is gasses mix easily so this "blanketing" with CO2 is not very likely in the real world.
 

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