Purging oxygen without CO2 tank

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Brewer dad

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I've searched here and Google, haven't quite found an answer yet. So thought I'd ask here as maybe it could help others.

I'm wondering about best methods, if any, for purging oxygen for those of us who do not yet have CO2. In this instance, I am asking most specifically about after either:

1. Opening fermentation vessel after fermentation is complete. I.e. dry hopping, adding fruit, etc.

2. After racking to secondary. To get off of yeast cake or to achieve either of above additions or maybe adding oak cubes. This would most likely happen with something I wanted to age some, but didn't have the bottles available. I'm pretty close to critical mass on bottles.

And as I'm sure someone will say it, yes I plan on moving over to kegging. However looking for alternative solution before I have CO2.

At the moment my thought would be to get a small amount of fermentation going again to push air out, achieved either by adding some sugar or fruit. In the former example I would assume maybe a 4-6 oz amount so as to only restart things long enough to clear out the air. My main concern is that by the time fermentation begins again, the oxygen absorption would have already occurred.

I did try this once when dry hopping in primary, and thought it turned out well. However that was a sample of one. Also not sure if it'd work for the second example.

I hope this isn't something that has been addressed and nauseum. Thanks!
 
A few suggestions if you are bottling...
  1. Don't use a secondary, unless you have to for adding fruit or other stuff that doesn't belong in primary
  2. If you cold crash, don't, unless you can capture some CO2 in a balloon and allow the fermenter to suck it back during the crash
  3. Use pet bottles and squeeze the liquid to the top to push out all air prior to sealing. See video.
  4. If you shake your bottles after sealing to mix - don't, this will oxidize you beer. See video.
 
You could go the cheap route and get one of the CO2 injector items and a box of cartridges to get CO2 on demand.
BUT, if you ever plan on kegging, I'd just get a bottle and [good quality] regulator and go that route. Since you'll be able to use it for the kegging setup later. You'll just be spreading the cost out a bit more. ;)

I actually have a regulator for paintball CO2 bottles that I've not been using (at all for many years). If you want it, let me know in a PM. Basically, pay shipping (USPS flat rate/pack mule) and it's yours.
 
Adding sugar boiled in water while dry-hopping is a fairly common practice, and I'd say it at least wouldn't hurt. You could always add a balloon to the top of the carboy at that point to collect some CO2 for cold crashing (if you cold crash) without it being so much it would blow the balloon up/off.

I second @Holden Caulfield (great moniker, btw) that you shouldn't secondary unless absolutely necessary. I've even added fruit to primary at the end of fermentation; I really only secondary if I'm bulk aging a beer for several months. I wouldn't worry about oxidation when adding fruit, as sugars in fruit will kick off fermentation anyway.
 
Adding sugar boiled in water while dry-hopping is a fairly common practice, and I'd say it at least wouldn't hurt. You could always add a balloon to the top of the carboy at that point to collect some CO2 for cold crashing (if you cold crash) without it being so much it would blow the balloon up/off.

I second @Holden Caulfield (great moniker, btw) that you shouldn't secondary unless absolutely necessary. I've even added fruit to primary at the end of fermentation; I really only secondary if I'm bulk aging a beer for several months. I wouldn't worry about oxidation when adding fruit, as sugars in fruit will kick off fermentation anyway.

To this point I've avoided secondary as a rule. One of the reasons I'm asking this is because I'm looking at bulk aging some stuff. Mainly certain malty/higher abv things that benefit from some time. As stated in OP I'm not looking to increase my bottle inventory much more at the moment.

Cool so it sounds like re initiating fermentation can help with what I'm looking at, thanks!
 
Why are you concerned about this? Is your beer bad, or is it just that you think you're supposed to worry about it?

Just trying to make the best beer I can with what I have available. I'm not losing sleep over it, but if I'm going to invest time into this hobby I'm going to try to do it right. So far my beer has been pretty decent but I see room for improvement.
 
Just trying to make the best beer I can with what I have available. I'm not losing sleep over it, but if I'm going to invest time into this hobby I'm going to try to do it right. So far my beer has been pretty decent but I see room for improvement.
I think I phrased my question poorly. I was really looking for your advice/experience. Your later post tells me you're looking at bulk aging. I was asking because I have at times bottled earlier than I wished, or delayed brewing because I didn't want my beer sitting around in a secondary too long. The idea of adding some sugar to ferment a bit sounded good to me. Would you treat this like bottling and just cork it, or would you use an airlock and then try to seal it up?
 
  1. If you shake your bottles after sealing to mix - don't, this will oxidize you beer. See video.

It will. But so will not shaking. i.e. the available oxygen in the headspace is the available oxygen in the headspace. Eventually, almost all of it will dissolve. Shaking does accelerate that though.

The way to keep beer fresh long term is to keep the O2 out in the first place. Which is IMO what the video really demonstrated (or at least started to). I wish he had done this in two trials... squeezing vs not squeezing and shaking vs non-shaking. Comparing not-squeezed-but-shaken to squeezed-but-not-shaken hopelessly entangled two variables.
 
The big ones to me would be dry hop while there is still some fermentation activity. Don't use a secondary. Don't use a leaky primary. Make sure the racking to the bottling bucket is gentle with no splashing. The best solution is to get the CO2 tank and regulator sooner than later, even if you can't afford a fridge and kegs immediately.
 
I wish he had done this in two trials... squeezing vs not squeezing and shaking vs non-shaking. Comparing not-squeezed-but-shaken to squeezed-but-not-shaken hopelessly entangled two variables.
And the oxidized, shaken but non-squeezed seemed to be more carbonated. It might imply that squeezed and shaken would have been best. FWIW, he did say something about not to rely on one test.
 
I think I phrased my question poorly. I was really looking for your advice/experience. Your later post tells me you're looking at bulk aging. I was asking because I have at times bottled earlier than I wished, or delayed brewing because I didn't want my beer sitting around in a secondary too long. The idea of adding some sugar to ferment a bit sounded good to me. Would you treat this like bottling and just cork it, or would you use an airlock and then try to seal it up?

No worries I should've given some background in the OP. Part of the reason I asked this is because I was given a few carboys, so I have a total of 5 fermentation vessels now. I have probably accumulated 150-175 regular sized bottles, basically enough for three five gallon batches with a couple leftover.

I am looking to age some stuff for fall/winter.Rather than tying up 30% of my bottles for several months my thought was to bulk age then bottle. My understanding is that after a month or so it's a good idea to get the beer off of the yeast cake, but I have also heard that secondary isn't a great idea either as already mentioned above. Which led me to trying to think of other ways to push oxygen out other than CO2 tank.

I have no experience with this but I would say air lock would be the way to go if you were going to have any fermentation going.
 
The big ones to me would be dry hop while there is still some fermentation activity. Don't use a secondary. Don't use a leaky primary. Make sure the racking to the bottling bucket is gentle with no splashing. The best solution is to get the CO2 tank and regulator sooner than later, even if you can't afford a fridge and kegs immediately.

Yeah biggest problem has been finding places to fill CO2 close by, but plan on doing things incrementally. Thankfully I have the fridge already.

So you don't think the secondary idea is worth it even with careful methods and fermenting to get oxygen out? I already practice what you described regarding avoiding splashing etc. I also bought some of those hop bombs, figured I could secure it inside fermentor with a magnet until ready to add.
 
This was already implied but if you can capture the CO2 produced during active fermentation in a balloon or keg, you can then use it for other things like back-flushing your headspace.
 
I just bought my first used CO2 tank and kegs. Still getting the process down and cleaning everything up before using. But the guy I bought them from said the CO2 tank was mostly full but that he hadn't had time to brew in 2 years. -There is no concern about using the CO2 that sat in a tank for 2 years, right? For now, I would just use it to purge headspace, but may be kegging a batch in about 3 weeks. Any input welcome.
 
Yeah biggest problem has been finding places to fill CO2 close by, but plan on doing things incrementally. Thankfully I have the fridge already.

So you don't think the secondary idea is worth it even with careful methods and fermenting to get oxygen out? I already practice what you described regarding avoiding splashing etc. I also bought some of those hop bombs, figured I could secure it inside fermentor with a magnet until ready to add.

You could get a double hole stopper and run a racking cane down to the bottom of the secondary carboy and put an airlock in the second hole. While the first one is fermenting, it's pushing CO2 to the bottom of that secondary (sanitized) carboy and flushing any air out of the airlock. That will leave it full of CO2. The only issue is when you transfer to that secondary, you don't have a CO2 source to backfill the headspace of the primary as the beer leaves. I'd still say it's twice as better as no purging. Just be careful about your closure on the secondary. Carboy caps are leaky. Oxygen eventually makes it through the water in an airlock even if it doesn't dry out.
 
Is swapping just simpler than keeping the same tank and refilling?

It will depend a bit on what is available around you. I have a few places where I can swap a tank (5# for about $30...an industrial gas place and a homebrew shop are the ones I have used), and one place where I can refill a tank (5# for about $22...a fire prevention store...when I went there I had to call to make sure the tech was in and it took 20 minutes).

A downside of refilling is that every 5 to 10 years a tank needs to be tested (I think it is 5 years for aluminum and 10 for steel). The industrial gas place, where I have done most of my swaps, is fine with swapping an out-of-date tank. I have never had to have it done, but my understanding is that most tests cost $20 to $25 and will likely take a few days.
 
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It's well known that oxygen causes staling and loss of flavor in beer that has finished fermenting. Whether you care or not is a different matter.

Why would one be skeptical of measurements of oxygen diffusion through polymers? This is also fully understood and well documented.


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You could get a double hole stopper and run a racking cane down to the bottom of the secondary carboy and put an airlock in the second hole. While the first one is fermenting, it's pushing CO2 to the bottom of that secondary (sanitized) carboy and flushing any air out of the airlock. That will leave it full of CO2. The only issue is when you transfer to that secondary, you don't have a CO2 source to backfill the headspace of the primary as the beer leaves. I'd still say it's twice as better as no purging. Just be careful about your closure on the secondary. Carboy caps are leaky. Oxygen eventually makes it through the water in an airlock even if it doesn't dry out.

That's an interesting idea. Kind of like guys using a keg full of starsan leading to a bucket as their airlock and then they've got a purged/sanitized keg. May have to give that a shot.

Thanks for the feedback!
 
So a valid take away from the article is that letting your ale condition in the primary for 10-14 days after fermentation has finished is not without some cost?

I am a bit curious how the info from that article would apply to real world brewing scenarios. While the idea of a "CO2 blanket" has been debunked, there is probably some protection from CO2 and beer will degas some CO2. It is enough to protect the beer from oxygen introduced through the airlock?

It makes me wonder more about long term aging. I pictured that Russian Imperial Stout aging for 6 months in a glass carboy with a standard stopper + airlock was fairly protected, but that might not be the case. I wonder if a mylar balloon partially filled with CO2 would provide more protection than an airlock.

I am curious about the Better Bottle Dry Trap mentioned. It seems rather pricey, maybe specific to Better Bottles, and might not be manufactured these days. I did see a link to this product: 841374 - Vented Silicone Stopper - Size 10
 
I am a bit curious how the info from that article would apply to real world brewing scenarios. While the idea of a "CO2 blanket" has been debunked, there is probably some protection from CO2 and beer will degas some CO2. It is enough to protect the beer from oxygen introduced through the airlock?

It makes me wonder more about long term aging. I pictured that Russian Imperial Stout aging for 6 months in a glass carboy with a standard stopper + airlock was fairly protected, but that might not be the case. I wonder if a mylar balloon partially filled with CO2 would provide more protection than an airlock.

I am curious about the Better Bottle Dry Trap mentioned. It seems rather pricey, maybe specific to Better Bottles, and might not be manufactured these days. I did see a link to this product: 841374 - Vented Silicone Stopper - Size 10

The test was measuring oxygen ingress of the closure as designed which is a combination of infiltration THROUGH the material it's made of as well as AROUND the closure in such cases that it had a loose fit. That's why the carboy cap performed so poorly. If I'm aging something in a carboy for a long period of time, I use a rubber stopper and cap it with a modified carboy cap with a hose clamp on it to hold everything snug. Stoppers sometimes pop out. Carboy caps are loose.

CO2 only provides some protection when fermentation is highly active and outflow of gas is deflecting incoming oxygen to some degree. It's definitely not going to stop all of it. Then when fermentation is done, that CO2 does nothing.

Honestly, I don't know why anyone would age a beer in anything with an airlock for more than a month unless it were a barrel or a sour, or both. Nothing beneficial that would happen in a carboy over months would be prevented from happening in a keg or bottle.
 
Honestly, I don't know why anyone would age a beer in anything with an airlock for more than a month unless it were a barrel or a sour, or both. Nothing beneficial that would happen in a carboy over months would be prevented from happening in a keg or bottle.

Lack of availability of the two would be the main reason, which is partly why I started this thread. I think for my situation at least I'll be better off adding some additional bottle inventory and aging there, rather than trying to force my original ideas to work. Or alternatively do some smaller batches with what I have. Thankfully I have space, and once I do get into kegging can use more bottles towards aging.
 
It's well known that oxygen causes staling and loss of flavor in beer that has finished fermenting. Whether you care or not is a different matter.

Why would one be skeptical of measurements of oxygen diffusion through polymers? This is also fully understood and well documented.


View attachment 729908
Good data but not accurate or even relevant when there is a pressure differential. Ferment under (even relatively low) pressure and you won't care about these data one whit. Of course, none of these numbers are large enough to make any difference to oxidation extent anyway.
 
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Good article about the oxygen permeability of different carboy closures.
https://longislandhomebrew.com/index.php?controller=attachment&id_attachment=519
Interesting study but it has at least two flaws. There are no replications of each closure. It is mentioned that closures were picked randomly but any one of those could be defective. Second, the data only seem to cover at most 2.5 hours, yet daily rates are reported. It is not appropriate to extrapolate like that, it would be like assuming your 100 meter time extrapolates to a 1600 meter time.

Something I noticed as well. There is an initial lag on many of the sampled closures, where the readings change from 0 to a mostly linear function (straight lines between points). Several of the closures this happens to are tapered stoppers. You have to wonder if they didn't just pop up slightly in the neck. Are they standardized stopper sizes (don't know, not stated)? Some stoppers fit the neck deep, some shallow. He should have marked them to see if they moved. This is one reason the lack of replication is an issue.
 
Something I noticed as well. There is an initial lag on many of the sampled closures, where the readings change from 0 to a mostly linear function (straight lines between points).

It is mentioned in the Test Results section on page 2...the green arrow indicates the point where the purging was stopped.
 
Good data but not accurate or even relevant when there is a pressure differential.

Once fermenation is finished, the pressures equalize. But even leading up to that, the gas exchange is not 0.

Ferment under (even relatively low) pressure and you won't care about these data one whit.

Some do care.

Of course, none of these numbers are large enough to make any difference to oxidation extent anyway.

Any oxygen makes a difference to oxidation. Large commercial breweries target dissolved O2 limits in low parts per billion at packaging. People (not you) often make the mistake of thinking that as long as oxygen exposure at any given step is less than the exposure at a different step, that the lesser exposure doesn't matter. Unfortunately it's additive. And oxidation is not binary. Every beer has some. The only valid debate is at what point it becomes noticeable, and how bad. And of course that depends on the style and the tasters' thresholds for various oxidized compounds, and even (gasp!) some tasters' preference for oxidized flavors. IOW, it's not all about cardboard vs not cardboard.
 
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If a beer oxidizes in the woods, but there is no one around who can taste it, does it still taste like cardboard?

That might be a trick question, since most beers, even ones with noticeable oxidation, don't taste like cardboard (when someone actually tastes them, not when they are untasted, in the woods).
 
Good data but not accurate or even relevant when there is a pressure differential. Ferment under (even relatively low) pressure and you won't care about these data one whit. Of course, none of these numbers are large enough to make any difference to oxidation extent anyway.

Even if you were right about oxygen not making it in when there is a pressure differential (you're not), that would assume that everyone removes the beer from the vessel the moment there isn't a pressure differential. I'm pretty sensitive to oxidation flavors, much to the dismay of brewers who's beers I judge in comps. I can assure you that beer is being regularly damaged. If all you brew is English styles where a little cask character is appropriate, you should care about oxygen damage.
 
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