Cold Crashing / Mylar Balloon

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CodeSection

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I have been reading about cold crashing and the introduction of O2 (and maybe StarSan) with suck back. Since I bottle and use a bottling bucket, I do not own a CO2 tank. Thus, I was trying to find another way to stop the suck back of O2. Here is what I found:

"Use a Mylar balloon that won’t require pressure to inflate. Install it on the airlock when you still have a few gravity points to go then let the completing fermentation inflate it. When you cold crash, the balloon will deflate without exposing your beer to anything other than the CO2 it produces."

This seems the way to go. So, with so many Mylar balloons to choose from with each having a different size hole to fill, what have you found that works with silicone tubing sized 3/4" OD? If you could provide a link, it would be much appreciated.
 
I'm confused why anyone would want to cold crash before bottling.

But yeah, I would use a bung with 2 holes: one for the balloon and one for an airlock or valve.
 
I'm confused why anyone would want to cold crash before bottling.

But yeah, I would use a bung with 2 holes: one for the balloon and one for an airlock or valve.

Presumably to limit the amount of sediment in the bottles. Even after crashing there's plenty of yeast to carbonate.
 
@RPh_Guy, it probably doesn't makes sense to spend money on a glycol chiller to cold crash if bottling. Especially since this is coming from a guy that drinks very little of the beer that is brewed. The cost of the glycol setup easily far outweighs the benefit of less sediment in the bottles. I was hoping to refine the process and output.....

@TheHopfather, thanks for the link! Interesting read. When I was on Amazon looking at the Mylar balloons, it appeared that some of the balloon's filling hole would be too small for the tubing I was using.

... Even after crashing there's plenty of yeast to carbonate.

So I'm told. I was told it may take an extra week to carbonate. I hope you are right!
 
What was said about using a stopper with 2 holes is spot on. One for the balloon, one for a blowoff tube. As for attaching the balloon to your tubing, don't over think it, you are dealing with a very small amount of pressure. Cutting away the filling adapter of the balloon, sticking in your tubing, and taping over it will work. Or you could tape in a short hard tube of a size that your flexible tubing will slip over.

There's some photos of how I rigged mine in this post.

I later updated my rig to use fermentation gas to purge my keg, as shown in this post.
 
I was using the Mylar bags, and I was throwing them away after every use because I was worried about cross-contamination between batches. You can't really clean them.
Plastic is oxygen-permeable, unlike mylar.

Why can't you clean mylar? How is it different than this plastic balloon?
 
I tried and the Starsan seemed to separate the foil from the plastic. Acidity maybe? Anyway it looked gross, and I just felt like I couldn't really get in there. Maybe just being paranoid.

I hadn't thought about the oxygen-permeability, but while there is pressure inside the balloon I would think it keeps that from happening. I'm not sure how much you'd get during the cold-crash period, but I would guess it's minimum over that kind of timeframe. Those are medical bags, so I would guess (I seem to be doing a lot of that) they are designed to have low permeability.
 
but while there is pressure inside the balloon I would think it keeps that from happening.
Pressure doesn't affect oxygen permeability at all.

I don't know which plastic that particular balloon is, but I would definitely want to know before implementing that as a solution. Some types let through significant amount of oxygen.
Still, it's better than nothing.
 
Pressure doesn't affect oxygen permeability at all.

I don't know which plastic that particular balloon is, but I would definitely want to know before implementing that as a solution. Some types let through significant amount of oxygen.
Still, it's better than nothing.
I wouldn't worry about mylar's permeability as that is a rather moot point if using silicone tubing. Silicone is just about as permeable to O2 as a pasta sieve...
 
I wouldn't worry about mylar's permeability as that is a rather moot point if using silicone tubing. Silicone is just about as permeable to O2 as a pasta sieve...

I'm in the process of moving to teflon tubing for cold-side stuff for that very reason.
 
Pressure doesn't affect oxygen permeability at all.

I don't know which plastic that particular balloon is, but I would definitely want to know before implementing that as a solution. Some types let through significant amount of oxygen.
Still, it's better than nothing.

So you're saying CO2 can't escape, but O2 can come in? I guess O2 is smaller. I was thinking equilibrium would keep things out, but I don't know how well. I'm sure the LODO brewers would be a great resource here.

I'm in the process of moving to teflon tubing for cold-side stuff for that very reason.


https://www.micromatic.com/1-4-inch-id-barriermaster-flavourlock-tubing-548bf

Is teflon better than something like this?
 
So I've been following this thread and attached a Mylar balloon to my airlock for 24 hours then cold crashed. At 24 hours there has been little to no suck back.

Just got me thinking is suck back during cold crashing that big of an issue for oxidation?
 
So you're saying CO2 can't escape, but O2 can come in? I guess O2 is smaller. I was thinking equilibrium would keep things out, but I don't know how well. I'm sure the LODO brewers would be a great resource here.

Actually, CO2 is escaping as well, there's just so much of it that it takes a while for the loss to become noticeable.
 
So you're saying CO2 can't escape, but O2 can come in?
Diffusion occurs. Gas molecules move from areas of high concentration to low concentration.
For a permeable balloon (or tubing, etc) filled with CO2, CO2 diffuses out and O2 diffuses in. The rates of diffusion are not the same because the molecules are not the same. However, the CO2 diffusing out is of no consequence.
 
The Mylar balloon seems to work well. Here is a pic from yesterday's brew of it filling up...

IMG_2270.jpg
 
Is that silicone tubing? :(

Yep. What do you recommend I use that will be large enough to fit on the 1.5" TC x 5/8" barb? I might someday buy Spike's PRV and a CO2 tank with a regulator to use while crashing. But since I have no plans to keg, I was trying to avoid those purchases.
 
Not doubt the question was wrt silicone being about the worst plastic wrt oxygen permeability.
PET lined tubing with whatever fittings needed to make the trip would be at the opposite end of that aspect...

Cheers!
 
Vinyl would be better, or you could wrap the silicone with adhesive PTFE tape.

Otherwise, that's a really cool setup!
 
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I can't recommend anything from EJ Beverage as their proprietary tubing has so little publically available data and what IS available suggests it's only incrementally better than solid PVC tubing wrt oxygen permeability.

PET is the way to go for the O2 adverse...

Cheers!
 
I tried reading EJ Beverage and EJ Medical tubing selection comparison. Unfortunately, it doesn't describe what their scale is based on other than "10" is the best.

Maybe I should go back and read the LODO sub threads, but are people also replacing their tubing on the hot side as well? I can see maybe when transferring the wort to the fermenter, but then again, you are oxygenating the wort anyway after pitching the yeast so that doesn't make sense to me.

In another thread, I read that some are even milling their grain so it is not as fine to reduce oxygen exposure. So maybe they have replaced their tubing on the hot side...all new to me.
 
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Yes, some uber-LODO practitioners have indeed found low-O2 permeable tubing for their hot side applications (those that aren't already hard-piped)...

Cheers!
 
I quit facebook 4 years ago. Best thing I ever did!

I keep an account for the sole purpose of screwing with the tons of people who wish happy birthday (to anybody and everyone). I log in (usually have to send off for new password again) about a month before my next birthday to thank everyone. I drives them crazy! I’ve seen where people (friends?) have continued to comment on the tardiness of reply damn near till it’s time to reply again. :yes:
 
are people also replacing their tubing on the hot side as well?
As I mentioned for one of your options, I'm wrapping my silicone tubing with PTFE ... I'm building a RIMS and also recirc through a CFC, so my wort is exposed to the tubing during transfers, throughout the mash, the latter part of the boil, and during chilling.
I got the idea from @Bilsch
Cheers
 
As I mentioned for one of your options, I'm wrapping my silicone tubing with PTFE ... I'm building a RIMS and also recirc through a CFC, so my wort is exposed to the tubing during transfers, throughout the mash, the latter part of the boil, and during chilling.
I got the idea from @Bilsch
Cheers

Exactly my process too. I cross circulate between the BK and the MT while mashing. During chilling, I cool though a CFC using ground water, then depending upon the time of the year, use an ice bath for the last 10-15 degrees.

If I understand correctly and ignoring the bulk sale on the link below, you are using adhesive PTFE tape like what is being sold at https://www.uline.com/Product/Detai...oated-Tapes/3M-5180-PTFE-Film-Tape-1-x-36-yds.

It says it conforms to irregular surfaces and is rated up to 500F. So, will it hold up or will it start to come off when you start cleaning your hoses? What about the affect of StarSan on the tape on the cold side transfer hose or blow off tubing?

I only use roughly 32' of tubing. Depending on your insight on how the tape holds up, it might be less hassle, less work and less time consuming to just buy 32' of PTFE tubing....
 
Exactly my process too. I cross circulate between the BK and the MT while mashing. During chilling, I cool though a CFC using ground water, then depending upon the time of the year, use an ice bath for the last 10-15 degrees.

If I understand correctly and ignoring the bulk sale on the link below, you are using adhesive PTFE tape like what is being sold at https://www.uline.com/Product/Detai...oated-Tapes/3M-5180-PTFE-Film-Tape-1-x-36-yds.

It says it conforms to irregular surfaces and is rated up to 500F. So, will it hold up or will it start to come off when you start cleaning your hoses? What about the affect of StarSan on the tape on the cold side transfer hose or blow off tubing?

I only use roughly 32' of tubing. Depending on your insight on how the tape holds up, it might be less hassle, less work and less time consuming to just buy 32' of PTFE tubing....
Yeah, I bought it here: https://www.amazon.com/gp/product/B000REJN48/

I don't have experience with it yet. There's discussion on this thread:
https://www.homebrewtalk.com/forum/threads/broken-mash-tun.667424/#post-8623900
 
Haha. I just finished reading that thread before I saw your response. Have you used the tape yet? If so, do you have pictures? I'm still leaning toward just buying new tubing....

Thanks for your help!
 
It's definitely cheaper and easier to just buy a new tubing if it's for cold side use.

It's only worth reducing O2-permeability of your tubing on the hot side if you're doing low-oxygen brewing.
 
No Matter what i did, i couldnt get a balloon to work as well as i was hoping. So i ended up picking up a 20oz paintball tank from my sporting good store, a mini co2 regulator off amazon, and now i just hook that up to my airlock when its time to cold crash. I put about 1.5-2psi on, and leave it during the cold crash. Then when i'm ready to transfer to my keg, i can do a fully closed co2 transfer. Works great so far
 
No Matter what i did, i couldnt get a balloon to work as well as i was hoping. So i ended up picking up a 20oz paintball tank from my sporting good store, a mini co2 regulator off amazon, and now i just hook that up to my airlock when its time to cold crash. I put about 1.5-2psi on, and leave it during the cold crash. Then when i'm ready to transfer to my keg, i can do a fully closed co2 transfer. Works great so far

My Mylar balloon has been working so far....though, only the second time using. Can you provide links and perhaps pictures of your set-up?
 

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