Physical concerns regarding cold crashing

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
T

trentm

Well-Known Member
Joined
Aug 16, 2007
Messages
324
Reaction score
63
If you have ever cold crashed beer after fermentation you realize the advantages of the process, e.g. clear beer with reduced maturation time. However, we are often concerned with the fact that air is introduced into the fermentor bringing with it possible contamination and oxidation. My concern is oxidation and it goes beyond just the exposure to air that is brought into the headspace.

Unfortunately, I do not understand the ability of a liquid to dissolve gas into solution but I know it happens. I think I know, for example that beer at 72F contains less dissolved gas (CO2) compared to beer at 40F (at atmospheric pressure). And I think that a gas will be dissolved into a liquid according to the amount the liquid can hold at a certain temperature and pressure. I also think that as beer is cooled it reduces in volume and that's why air is sucked into the fermentor. So when we cold crash beer it will try to find that equilibrium and dissolve a significant amount of whatever gas is available. I'm not a mathematician either but using a bottle conditioning calculator, through trial and error, I found (if correct) beer at 40F can hold ~0.57 volumes of gas more than beer at 72F. That seems like a lot of gas and if even part of it were air that may be a significant amount of O2. So if my understanding is correct, the air that is being taken into the fermentor is not just mixing with the CO2 in the head space but the cold beer is "sucking" it into solution.

Please excuse my lack of knowledge and correct terminology on this subject. If my thoughts are comprehensible, please express your opinion of this thesis.
 
I've oxidized IPAs that way. They tend to be highly susceptible though. Actually I have stopped cold crashing because this is what happens in the keg/bottle anyways. As long as your not shaking them up what would be the difference?
 
Yes beer (or water) dissolve more CO2 and oxygen when cold and they do shrink in volume though there is expansion near freezing. When beer is cold crashed it is usually in a unitank at positive CO2 pressure provided by a regulator so that 1) there is plenty of extra CO2 available to dissolve and 2) no oxygen gets drawn in even though the headspace volume increases.

If you crash beer in a carboy it is still under a blanket of CO2. Even though the reduced volume may draw in some air it should 'float' on top of the CO2 blanket affording some protection. But clearly if you have a small headspace and cool things enough you might dissolve all the CO2 in that headspace and air might have access to the surface of the beer. Keep in mind that CO2 is much more soluble than oxygen but at the same time it doesn't take much oxygen to ruin your day.
 
I see folks talk about blankets of CO2 protecting beer, but I don't believe this at all. Any gases will mix to form a homogeneous solution. If CO2 truly formed protective blankets, on non-windy days we'd see a lot of folks in valleys suffocating in the CO2 exhaled from the people living up hill from them. Fact is that the blend of gases you get on the top of Mt Everest is about the same as what you get in Death Valley - there is simply a lot less of all the gases on Mt Everest (there's a lot more space between the gas molecules). So, with any given breath, the poor guy on Everest is getting a lot less of everything than the guy in Death Valley. The guy on Everest isn't just getting less oxygen - he's getting the exact same percentage of everything just a lot less in total.

Yes, CO2 is more dense, but non-reacting gases always blend to form a homogeneous solution - sometimes it takes time, but it'll happen.

What we do to protect our beer is to introduce more and more CO2 to dilute the other gases. Yeast do this on their own. We do this with bottled gas. The yeast produce CO2 and the airlock releases a blend of CO2 and "air" (which has O2). Since the airlock prevents new O2 from coming back in, we have less and less O2 to wreak our beer. We do the same thing in a keg - pressurize with CO2 and release CO2 and air; repeat again and again. You end up with very little oxygen mixed with a vast majority of CO2.

Then, we open the fermentation bucket after the yeast are done with the majority of their work to drop some dry hops in. Air is introduced into the head space - and it blends with the CO2 to form a homogeneous solution. If we don't do anything to dilute the oxygen (by introducing more CO2), your beer is exposed to oxygen. Will it be oxidized? Probably not - it depends on how much gets introduced and how sensitive your beer is to oxidation. However, to state that the CO2 that is present forms a protective blanket, is rubbish.

Can gas density be used to separate gases? Yep. But that is hard - just ask the folks that make fissile material. They use centrifuges that work at thousands of times the force of gravity. But, at standard gravity, the protective blanket isn't there. Gases diffuse and entropy makes it hard to undo that mixing.
 
I'm not sure if you're looking for confirmation on your thoughts or an answer. As previously mentioned, cold crashing can create suck back.

Personally I cold crash every beer, I use an "s" type airlock filled with vodka and generally I have maybe a half gallon headspace in my buckets. Not one beer has ever become oxidized in my process so my conclusion on this is the residual co2 present does a good job of protecting my beer for the few days of crashing.
 
trentm said:
If you have ever cold crashed beer after fermentation you realize the advantages of the process, e.g. clear beer with reduced maturation time. However, we are often concerned with the fact that air is introduced into the fermentor bringing with it possible contamination and oxidation. My concern is oxidation and it goes beyond just the exposure to air that is brought into the headspace.



Unfortunately, I do not understand the ability of a liquid to dissolve gas into solution but I know it happens. I think I know, for example that beer at 72F contains less dissolved gas (CO2) compared to beer at 40F (at atmospheric pressure). And I think that a gas will be dissolved into a liquid according to the amount the liquid can hold at a certain temperature and pressure. I also think that as beer is cooled it reduces in volume and that's why air is sucked into the fermentor. So when we cold crash beer it will try to find that equilibrium and dissolve a significant amount of whatever gas is available. I'm not a mathematician either but using a bottle conditioning calculator, through trial and error, I found (if correct) beer at 40F can hold ~0.57 volumes of gas more than beer at 72F. That seems like a lot of gas and if even part of it were air that may be a significant amount of O2. So if my understanding is correct, the air that is being taken into the fermentor is not just mixing with the CO2 in the head space but the cold beer is "sucking" it into solution.



Please excuse my lack of knowledge and correct terminology on this subject. If my thoughts are comprehensible, please express your opinion of this thesis.
Click to expand...


First, you're absolutely correct re the solubility of a gas, that is, the solubility is inversely proportional to the temperature. More CO2 will be dissolved (absorbed) in colder beer.
If you're cold crashing in a keg you would/should have purged it w/ CO2 so there's no O2. If you're cold crashing in a carboy you can always put in so CO2 in any deadspace @ the top.
I prefer to keg condition then cold crash & it's ready to serve.


Sent from my iPhone using Home Brew
 
I have cold crashed every brew I have done, I keg and I like the fact the beer is ice cold going into the keg

no need to cool it down it is already cold when I put it on gas, I like the fact that the yeast cake is so firm and the beer is so clear

I have only been brewing since July 2013 but in the 43 11.5 gallon batches I have brewed I have not noticed a problem

all the best

S_M
 
Perhaps you should. Examples of the ability of a heavy gas to displace a light gas abound. If you have ever ridden a motorcycle at night you will know that cold air collects in depressions. You have probably seen a candle extinguished in one pitcher when CO2 from another is poured in. You probably know that an insurance adjuster knows that a house with its roof blown off has (had) natural gas service whereas one with its basement blown out was served with propane. You may be aware that any device with an open flame must have its pilot and burners more than 18" above the floor of a communicating garage. Or perhaps you have seen the 'vapor' from a block of dry ice sitting on a table roll off the ends and sink to the table surface. As to CO2 in a fermenter I can personally attest that you don't want to reach down into one even after the lid has been removed for some time.

I think we would agree that if we had a cylinder divided in half by a partition and put a light gas in one half and a heavy one in the other and then removed the partition that the light gas would move into the heavy one more quickly than the heavy one into the light one (even if oriented vertically with the heavy gas on top) but that eventually there would be equal amounts of each gas in the two halves - thermodynamic equilibrium demands it. By similar thinking I expect that if I had stuck my head into that fermenter two weeks later than I did it probably would not have gotten the surprise I did. But a week later? A day later? That would depend on many things but clearly mixing would profoundly effect how long it took to reach equilibrium. WRT to CO2 in the atmosphere (in, which, note, that the denser air is at the bottom) it is clearly mixing that is responsible for the fairly uniform distribution (though Fick's law suggests that even without mixing we would eventually come to this uniform distribution).

I don't think you'd have any problem accepting that if I filled a balloon with CO2 and dropped it into a box full of air that it would rapidly sink to the bottom and stay there. If I could remove the balloon without causing gas currents I think you would probably agree that the blob of CO2 would flow out over the bottom of the box displacing air until there was a layer of uniform thickness over the bottom. Then I think you would agree that over time air would diffuse into the CO2 layer and CO2 would diffuse into the air with the relative rates determined by Graham's law. Of course in a fermentation fresh CO2 is always being pushed up into the bottom layer as long as the fermentation is active. When it stops then diffusion becomes the enemy.

Thus it is apparent that the CO2 blanket is quite real. The question is how long does it persist (or for how long does it continue to provide protection) once the CO2 evolution ceases.
 
Yes! I agree with everything you have said.

However, as you stated, gases will mix given time. So, if I pop open a fermenter, I'll introduce O2. It can't be helped. And it will mix with the CO2 that is present. That O2 can cause oxidation. Will it definitely? No - perhaps not to the level that is noticeable. But I will say that since I've been extremely cautious about O2 exposure during dry hopping; transfers from primary to bottling bucket; and into the bottles, my IPAs have gone from pretty crummy to pretty darn good.

This is all semantics. When I picture a protective blanket of something, I envision a layer that will not be penetrated. In the case of CO2 though, this is not the case. Once I expose the CO2 to air, the O2 will mix in and the O2 will definitely get to the beer. All the gases need is time to do so.
 
Well stated Adjalenge. That's precisely why purging with CO2 works. CO2 is heavier than O2, and thus you can displace it. I often rack to secondary glass (yah, yah, I know), purge with CO2, and age. I usually keg before cold-crashing, but it's personal preference IMO. I like aging at 60 over 35. . .
P
 
duboman said:
I'm not sure if you're looking for confirmation on your thoughts or an answer. As previously mentioned, cold crashing can create suck back.
Click to expand...

First, thanks for all the replies.

Well I am not really looking for confirmation or an answer as much as discussion in an attempt to understand how much effect that air may have on the finished beer. Of course everyone who has cold crashed a beer knows that gas (whatever gas is available) is taken into the fermentor and without some type of intervention that gas is air. If the air is just in the headspace, perhaps as stated in at least one reply, it is not causing any harm. However, as stated, my hypothesis is; the issue may go beyond just bringing air into the headspace but that air may actually be dissolved into the beer do to the ability of the beer to take in more gas as it cools. If that is case, I believe there would, eventually at least, be a deleterious effect on the beer.

Some replies have agreed that air could be dissolved into the beer but may have little effect as staling of beer due to O2 exposure takes time and beer should not be aged. That is true for many beers and for those beers the consequence may be limited but for the type of beer I brew (big Belgians) benefit from ageing and are not really worth drinking until after at least 3 months and peak at 6. After 6 months my beers will often begin to go downhill and I would like to find ways to remediate that because those that don't, continue to improve.

Let me come clean here. I like to cold crash because it seems to shorten the long maturation time of my style of beer. However, the stated hypothesis has caused me to take action to reduce the possibility of oxidation and that action has further complicated my already complicated process. I'll describe the process with the caveat that it may not work with yeast strains that are highly flocculant. One of the challenges with brewing big Belgians is the fermentation never seems to fully complete. The yeast are slow to flocculate and will continue to ferment at a very low level for what seems to be about 6 months as observed by an increase in carbonation over that period of time. What I have found is: after fermentation is apparently complete (no measurable drop in gravity between reading taken 4 days apart) if you slowly bring the temperature down by ~2 degrees F per day, CO2 production will remain at a level that will keep up with the shrinkage of the beer and no gas is taken into the fermentor. Unfortunately this is not exact and some days the temp cannot be reduced as determined by the action of the liquid (I use EtOH) in the S type airlock. So the process cannot be automated and must be determined each day as to whether to drop the temp or not. The process in onerous. Because of the time involved in determining the outcome of this process, I have not yet been able to judge the effect. That's why I am putting the hypothesis out for discussion.

I noted in the OP that I calculated that 0.57 volumes of gas may be dissolved by bringing the beer down from 72F to 40F. I was hoping to get confirmation on that calculation as well as an understanding of what that means. I don't really understand what a "volume" of gas is and how it would relate to the amount of gas in the headspace of a fermentor.
 
Trentm,

A volume is (as I understand it) the amount of gas a liquid holds - so, if I poured a pint of beer that was carbed to a level of two volumes, I could (in theory) get two pints of CO2 out of it.

To keep your beer from getting exposed to air from cold crashing, you have to keep air from getting sucked back in to your fermenter. Probably the easiest way to do this (other than not crashing) would be to keg your beer and cold crash in the keg under a few psi of CO2 from a bottle.

I stopped cold crashing because of the issue with air being drawn in. However, I can not state that this had a significant impact on my IPAs. I went "all out" against O2 - no incremental steps. As a result, I can't say that cold crashing does definitely result in oxidation. However, I will say that it does result in exposure of your beer to oxygen. Gases mix given time. Those mixed gases will be absorbed by your beer. My all out effort against O2 exposure gave my IPAs the flavor I was shooting for and a better shelf life.

I went to a local brewery and talked to one of the owners about oxidation. He talked about the lengths that they go to to keep oxygen down to the "parts per billion" level. As a result, they can get a shelf life of a few months on their IPAs before things turn bad. But even then, you can note differences between the beers that have been bottled for days or weeks. We sat down and tasted a range of bottles (all the same beer just different times in the bottle). This taste test is what made me try to minimize oxygen exposure.

Good luck! It would be interesting to hear what your results are if you figure out a way to cold crash without letting air in.
 
6 months is highly ambitious and quite an accomplishment in itself. I am currently at the 3-4 month mark.

With Belgians you would have to account for the yeast/hops flavors dropping out more than oxidation I would think. There is only so much 02 in a beer unless your carbonation method is continually adding it (headspace in bottle, poor seal in cap etc..) and I would think by 6 months the effects of the original 02 in solution would have played out already (hot side aeration aside).


The amount of vacuum wouldn't decrease with incremental temperature drops. It is constant. More likely your just not pulling with enough force to move the water in the airlock and all air is coming in through the tiny gaps in your fermenter seals.


Here is a good thread explaining volumes:
https://www.homebrewtalk.com/f14/volumes-co2-105955/

Note that not all gases may dissolve at the same rates given equal temp/pressure. For example, if c02 is heavier than air it is more likely to be at the surface of the beer than the 02 in the air drawn in. Being at the surface would make it more likely to dissolve.
 
For longevity in the package O2 is, for certain, the bete noir. It is quite possible to keep beer for well over a year, even two, if one is scrupulous about oxygen exclusion. I do this as a matter of course. The last time the beer sees any O2 is when the O2 is shut off after it is in the fermenter. The yeast consume the injected oxygen and presumably some of what is in the headspace. The rest gets expelled with air as the CO2 formed by the fermentation blankets the beer and pushes the lighter nitrogen and oxygen out the vent port at the top. When there are still a couple of °P the tank is spunded so it stays at positive CO2 pressure as the temperature is lowered and is still at appreciable positive pressure for the conditioning hold near freezing. During conditioning a CO2 bottle is attached to make up for slow leakage in the fermenter. When it is time for the beer to go into kegs they are steam sterilized for long enough that all the air is swept out and when cooled the collapsing steam is replaced by CO2 at a couple bar. The kegs are then counter pressure filled against that CO2. I doubt I've eliminated every last microgram of O2 by these methods but the beer is, as I said above, stable wrt oxidation, for better than a year.
 
I'll comment. I think it's rather a brilliant idea for keeping the beer under positive CO2 pressure after fermentation has terminated. One could envision adaptations of the idea such as a rubber glove with with the wrist secured to the neck of a carboy and a line connected via one finger to a CO2 bottle set for low but finite gauge pressure.
 
LabRatBrewer said:
If there was a vigorous, the balloon would pop way before the carboy, yes?
Click to expand...

Why would there be a vigorous anything after fermentation is complete? If you're that worried about it, just get one of those long balloons the clowns use to make bicycles with.

Passedpawn. I think that idea is brilliant and it's something I'm going to try next time around.
 
LabRatBrewer said:
If there was a vigorous, the balloon would pop way before the carboy, yes?
Click to expand...

Not when I did it. In fact, it didn't inflate much. I put the balloon over the airlock, but next time I'll probably stretch it over the mouth of the carboy and see how that turns out.

Either the CO2 was being forced into solution, or it was escaping. If escaping, it might have been pushing out of unseen gaps, or the CO2 molecule is smaller than air (N2) and it just pushed through the skin of the latex balloon. I don't have the desire right now to figure that out (might ask my chemsitry whiz son tonight).
 
I'm intrigued, I would think placing the balloon just as fermentation is finishing would provide enough co2 to inflate enough and contain enough gas for a decent period of time to protect the beer. Curious though about the latex, most balloons my kids brought home were partially deflated the next day.
 
grathan said:
Note that not all gases may dissolve at the same rates given equal temp/pressure. For example, if c02 is heavier than air it is more likely to be at the surface of the beer than the 02 in the air drawn in. Being at the surface would make it more likely to dissolve.
Click to expand...


True - not all gases will dissolve at the same rate, but it has nothing to do with CO2 being closer to the surface of the beer because of its density. The gases will mix completely in spite of the differences in density.

Check out the this demonstration of diffusion. The diffusion of bromine and air is shown. Although bromine is approximately seven times more dense than air, they mix. In the demo, the mixing took about 30 minutes.



CO2 is only about 1.5 times more dense than air. So, if bromine won't form a protective blanket, CO2 won't either. Gases diffuse given time - we're usually talking weeks; the OP is talking months. That is more than enough time for the air drawn in by cold crashing to mix with the CO2.

By the way, passedpawn, good idea about the balloon - save the CO2 to replenish the head space!
 
Last edited by a moderator:
BreezyBrew said:
Why would there be a vigorous anything after fermentation is complete? If you're that worried about it, just get one of those long balloons the clowns use to make bicycles with.

Passedpawn. I think that idea is brilliant and it's something I'm going to try next time around.
Click to expand...

I thought the idea was to place the balloon during fermentation so that it would inflate with co2 from the fermentation, and then that co2 would be sucked back at the cold crash. My question was because trapping the gas could increase the pressure in a carboy which gives me pause (though I would expect the balloon to fail first)
 
Tried something different with my latest beer. It's an alt with wyeast 1007 which is very low floc. I wanted to cold crash and gelatin. I left the blow off tube on during crashing.

Here's the result after coming down from 68F to 38F before replacing with a 1 piece airlock. I circled the two starsan liquid levels.

I did this partly as an experiment, but it seems like a reasonable approach, no? The blowoff tube should be filled with co2 so no oxygen came into the headspace at the point this pic was taken.

IMG_0560.jpg
 
Agreed - seems like a reasonable approach. The blowoff tube ought to have had essentially all O2 flushed out if it. Of course, the only risk is that you'll suck sanitizer back in to you beer during the crash. Obviously, you did not (based on the levels you indicated in your blowoff tube).

I suppose one could determine the volume needed in a blow off tube to accomplish the crash while still protecting the beer. I'd guess that the coefficient of expansion of water would be a good place to start. Given your temperature drop, determine how much the volume of beer will decrease. Make sure your blowoff tube and blowoff container have more than that volume.

Seems simple enough!

Edit: one more thing to consider! It's not just the coefficient of thermal expansion of the beer to consider, it's the total headspace as well - including the blowoff tube itself. So, the headspace contracts AND the beer contracts. Not just the beer.
 
D-Train said:
Tried something different with my latest beer. It's an alt with wyeast 1007 which is very low floc. I wanted to cold crash and gelatin. I left the blow off tube on during crashing.

Here's the result after coming down from 68F to 38F before replacing with a 1 piece airlock. I circled the two starsan liquid levels.

I did this partly as an experiment, but it seems like a reasonable approach, no? The blowoff tube should be filled with co2 so no oxygen came into the headspace at the point this pic was taken.
Click to expand...

Hey, looks like that worked! And is shows how much air, if left uncontrolled, would otherwise be taken into the carboy. It does look like it was dangerously close to going over. However, I guess the star-san would have saved to day.
 
Your assuming the seal is airtight. A good test would be how long can it hold the star san in the tube. Also the headspace will vary batch to batch unless you meticulously fill to a specific point every time.

It is interesting though. Perhaps just a wider section of tube would be sufficent. I wonder if the vacuum could draw bubbles up the tube.
 
With regard to oxidation, wont the rate of that reaction occur much more slowly at 38F than 68F?
 
One aspect of diffusion that I keep forgetting to comment on is that the rate of diffusion depends on what the gasses are diffusing through. In the video demo they are diffusing through the equally wide jar mouths and it takes half an our. Later in the video the bromine is in a small tube attached to a larger tube, full of air, through a stopcock. When the valve is open, if the smaller container is at the same pressure as the larger, the diffusion will still take place but it takes much longer. Similarly in a fermenter. If we are talking Yorkshire squares the diffusion will be relatively fast in comparison to a carboy in which the CO2 blanket is perhaps 50 cm in diameter and the mouth of the carboy 5. The same level of diffusion should take about 10^2 = 100 times longer. Rate of diffusion also depends on sqrt(T/m). The hotter the gas the quicker the diffusion and the heavier it is, the slower.
 
ajdelange said:
If we are talking Yorkshire squares the diffusion will be relatively fast in comparison to a carboy in which the CO2 blanket is perhaps 50 cm in diameter and the mouth of the carboy 5. The same level of diffusion should take about 10^2 = 100 times longer. Rate of diffusion also depends on sqrt(T/m). The hotter the gas the quicker the diffusion and the heavier it is, the slower.
Click to expand...


Correct. However, this was not really the OP's posed issue. The issue concerned the air introduced to the headspace as a result of cold crashing.

Assuming a 30°F drop in temperature during a cold crash, you'd get about 6% air mixed with 94% CO2 in the headspace. Volume2/Volume1=Temp2/Temp1 if I assume the pressures at the beginning and end of cold crashing are the same. I've also ignored the contraction of the fluid volume as being small relative to the change in the gas volume. And, of course, the temperatures are measured on an absolute scale (K or °R). Once that 6% of air is drawn in to the headspace, it will not take long to diffuse in to the CO2.

If the issue were simply removing the airlock, then your point would be absolutely relevant - it would take a long time for the air to mix completely with the CO2 in the headspace.

So, I agree - removing the airlock will not introduce a significant amount of air into a carboy. But, cold crashing will (depending on the amount if headspace). And the air will mix with the CO2.
 
It is understood that you don't want to draw any air in. That's why the rubber glove suggestion is so brilliant. It not only prevents air from coming in but indicates that there is still positive pressure even after the crash so that you know it is safe to remove the rubber glove. Ideally you would replace the rubber glove with the airlock thus excluding oxygen incursion altogether.

Better still, of course, is to do this in a sealed cylindroconical and crash only if you have enough positive pressure to insure at least 0 psig at the conclusion of the crash. This is, in fact, identical to what we would be doing with the glove and carboy and only better in the sense that it is easier to manage.
 
Or just ferment in kegs with a pressure relief valve on the gas fitting. You'll keep the CO2 dissolved from the beginning and ensure O2 is eliminated. Then when you cold crash you don't have to worry. And as long as you transfer cold the CO2 will stay dissolved and not foam when transferring to the keg or bottle. Plus you can pressure transfer without having to open the fermenter and letting in a gulp of air.
 
johngaltsmotor said:
And as long as you transfer cold the CO2 will stay dissolved and not foam when transferring to the keg or bottle.
Click to expand...
A bit of topic drift here but you don't even have to transfer cold if you transfer against CO2 counter pressure. Presumably you would transfer cold, though, as you have just crashed. For minimum O2 pickup you still want to counter pressure transfer.
 
Put a tee in the blowoff line that leads to a deflated mylar balloon. The balloon will inflate full with CO2 during ferment and the excess will vent to the blowoff basin. When negative pressure is introduced, the CO2 sucks out of the balloon. This solution can be implemented at any time during active primary and doesn't need special timing.
 
This person had an interesting idea. They used a Mylar balloon to capture CO2 and then used the harvested CO2 to carbonate their beer. Same concept can be used to protect the headspace during cold crashing.

http://www.angelfire.com/cantina/carbonation/

Bobby_M's idea is pretty slick. The balloon acts as a CO2 reservoir until it fills, then the excess goes out through the airlock. Then during cold crashing, the reservoir is used to refill the headspace. Nothing to adjust - fully automatic.
 
That is a neat idea with the bicycle pump. I wonder if they can be used to vacuum a keg.
 
Thanks for all the discussion and tips. I decided to try the balloon trick using a Nitrile glove (powder free), and per A.J.'s suggestion use one finger of the glove as a fill tube. The wrist of the glove was secured with several laps of electrical tape stretched tight. The very tip of the index finger was clipped with scissors and the glove was inflated and released 5 times to purge O2. After final inflation, the index finger was tied tightly closed. Seems to have worked great. The first image below shows the gloves inflated at 72F. The second is 48 hours later at 34F (sorry for the dark image). While the gloves deflated significantly there is still apparently CO2 present.

Question: Would it be best to replace the gloves with an airlock after the desired temperature is achieved?

IMG_0378.jpg


IMG_0384.jpg
 

Similar threads

IrondaleBrewing
How to Cold Crash in Fermonster with Airtight Lid?
Replies
16
Views
681
Bobby_M
Bobby_M
A
Cold Crashing ?
Replies
11
Views
1K
mac_1103
mac_1103
P
Cold Crashing Method
Replies
29
Views
2K
Parametric Brewing
P
T
Kegland Duotight Inline Regulator for Cold Crashing?
Replies
13
Views
916
Brooothru
Brooothru
joshred4
New to kegging and getting frustrated with oxidation
Replies
32
Views
2K
franknbeans
franknbeans
InkBird 300

Latest posts

Back
Top