Purging bottles with CO2?

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nasmeyer

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After reading about Blichmanns beer injector that purges the bottle with CO2 when bottling from a keg, I was wondering if someone bottling out of a bottling bucket could improve thier brew by using a small CO2 mini-injector, and purge the bottle of oxygen. I would guess that the yeast need oxygen to carbonate, but was also wondering if enough oxygen would still be present in the beer for the yeast to do their thing. Anyone try this before? would it actually make any improvement, or would it be a waste of time and money?
 
I don't know (really, no idea) if this is correct or not, but it seems to me like oxygen in the headspace of a bottle, when carbing in the bottle, shouldn't be a problem. I'd guess the yeast would use it up.
 
That's a little paranoid actually. It's not that crucial. When we are filling from the bottom, we are actually purging the o2 out of the headspace with the co2 we brought over that was already in the beer. As you are overflowing the lip of the bottle a little bit, before pulling the wand back to create the headspace, you have just purged out the oxygen,.

THEN if you leave the caps loosely on top of the bottles for a few minutes before capping them, as recommended in just about every brewing book I have ever read, you are allowing the blanket co2 that came over with the beer, as well as the new co2 being created, to push out any leftover oxygen.

If you've ever had a bottle cap or two pop off before capping them then that is the o2 being voided out of the headspace.

Besides one could even argue that if there were any o2 left in the headspace it is gobbled up by the yeasties as they are fermenting the priming sugar...so a little is a good thing.

RDWHAHB. You don't need to overthink/overkill this. Billions of bottle a year are filled by homebrewers without doing this, and I would venture to say they have the same experiences as I do...no issues with it that would warrant the extra step. ;)

If you haven't already I encourage you to read my botlting thread...https://www.homebrewtalk.com/f35/bottling-tips-homebrewer-94812/
 
That's a little paranoid actually. It's not that crucial.

This isn't a paranoid question at all. It's a good one. It's why breweries go to great lengths to purge their bottles with CO2, not once, but multiple times before the cap is ever sealed. O2 has a major impact on flavor, particularly on aroma hops. Vinnie Cilurzo at Russian River goes to great lengths to get people to drink his hoppy beers early, before the hops are oxidized.

Besides one could even argue that if there were any o2 left in the headspace it is gobbled up by the yeasties as they are fermenting the priming sugar...so a little is a good thing.

O2 in the headspace is never a good thing. Yeast work on the O2 in solution, not the O2 in the headspace, and yeast die long before the gobble up all of the O2. They're nowhere near that efficient.

Billions of bottle a year are filled by homebrewers without doing this

There is an ungodly amount of Colt 45 consumed each year as well, but that doesn't make it taste good :)
 
I agree with ocluke. I believe Palmer states in one of his writings that the yeast only use up around 30% of the oxygen in the headspace. The rest of oxygen has significant impact on hop aroma and flavor. Hop aroma compounds are very susceptible to oxidation- if you have ever had a growler filled with IPA, it has a shelf life of about 3-4 days before it starts tasting blander, sweeter, less aromatic. That gives you an idea of the impact of that headspace of O2 on hop flavors.

As far as a method of purging, that is why I clicked on this thread! A 5lb co2 tank with an attached air gun to the regulator is my idea. I don't know much about CO2 systems though, so I am afraid of blasting beer out of the bottle and into my face.
 
Assuming the correct amount of priming sugar as added, and the beer had viable yeast, would having the headspace filled with purged c02 create more carbonation or too much carbonation due to the c02 being introduced where 02 would normally be?
 
Just thought I would post this here for anyone that comes across this thread because I had oxidation issues when bottling for a long time.

I did a minor experiment recently to determine the effect of purging the headspace in the bottle with CO2. Very simply, I bottled all beers as I normally would by purging my bottling bucket with CO2, transferring into my priming solution in the bucket and then bottling. All bottles where purged with CO2 prior to filling. Some bottles had the headspace purged with CO2 after filling and where then immediately capped off (will be referred to as "Purge"), and the others where not purged with CO2 but had the caps placed on them and sat for a few minutes before capping (will be referred to as "No Purge").

6 weeks past and 2 vastly different beers resulted... I would have liked to have checked them at week intervals, but life got in the way and in all honesty, I forgot about them for a while.

Not only are they visually very different with "No Purge" being much darker and having a head of bubbles that where much more fine than "Purge", "No Purge" I don't think I would even be able to call an IPA anymore if evaluated solely on flavor and aroma. Nearly all hop character was masked by a sickly sweet aroma reminiscent of over-ripe fruit/honey and very off-putting flavor. Whereas "Purge" had a nice citrus hop flavor and aroma. I was still able to detect a hint of oxidation in "Purge", however, but it was not nearly as pronounced as "No Purge".

All in all, if I ever bottle another batch from a bottling bucket (I always keg now), I will be purging the headspace with CO2.

Keep Brewing,

:mug:



Left = Headspace purged with CO2.... Right = Headspace not purged with CO2.

OxidationIPA.jpg
 
This isn't a paranoid question at all. It's a good one. It's why breweries go to great lengths to purge their bottles with CO2, not once, but multiple times before the cap is ever sealed. O2 has a major impact on flavor, particularly on aroma hops. Vinnie Cilurzo at Russian River goes to great lengths to get people to drink his hoppy beers early, before the hops are oxidized.



O2 in the headspace is never a good thing. Yeast work on the O2 in solution, not the O2 in the headspace, and yeast die long before the gobble up all of the O2. They're nowhere near that efficient.



There is an ungodly amount of Colt 45 consumed each year as well, but that doesn't make it taste good :)

Comparing the way commercial breweries bottle beer and homebrewers is not realistic. The commercial brewery is bottling thousands of bottles at one time. They have the equipment to do it. etc. I would like to see something about how many commercial breweries purge, and how many purge multiple times.

I would say if you are bottling correctly, even without purging there is very little if any oxygen left in the bottle.

If it were a big problem there would be thousands of people complaining about their beer on HBT.

Is it a good idea?? Maybe. Will it make your beer better? Maybe. Will your beer suffer if you don't? I would say no. Is it necessary? I will say absolutely not.
 
Just thought I would post this here for anyone that comes across this thread because I had oxidation issues when bottling for a long time.

Just found this as I'm googling the subject. I'm curious, how much CO2 is needed to purge a 12oz bottle? And then the head space? Just a couple seconds, or? I've been battling oxidation issues and just got a small CO2 bottle and a regulator, so it's going to be my first try.

Any input appreciated!

Cheers!
 
I'm sure a couple seconds would do it. I had similar oxidation issues as post #7 when bottling my IPAs. Shelf life was terrible and the beer color and flavor would go downhill in a matter of weeks. I've stopped bottling and won't even attempt it again unless I get a counter pressure filler down the road.
 
Just found this as I'm googling the subject. I'm curious, how much CO2 is needed to purge a 12oz bottle? And then the head space? Just a couple seconds, or? I've been battling oxidation issues and just got a small CO2 bottle and a regulator, so it's going to be my first try.

Any input appreciated!

Cheers!

I use blichman v2 . 5 to 6 seconds purge then fill then as I pull the wand out i hit it for 2 bursts of co2 then cap
 
Since I have started working on NEIPAS I am very keen to understand this more. If I purge the bottles with co2 + rack the beer to the bottle + purge again the top space + then cap it. Do I need to somehow take this in consideration when I am calculating the priming sugar?
 
Since I have started working on NEIPAS I am very keen to understand this more. If I purge the bottles with co2 + rack the beer to the bottle + purge again the top space + then cap it. Do I need to somehow take this in consideration when I am calculating the priming sugar?

No , and theres no need to purge the bottle before you fill with primed beer for carbonation.
 
No idea how others normally purge, but want to share how I did it because it was very easy and also allowed me to stop for periods of time as necessary (I was also brewing that day) without paranoia. The two 'tricks' were that I bottled from a keg and I purged using a bottle filler. That plus a vice and some tape helped, too. This requires a keg, obviously, and also either two CO2 tanks or a tank with a splitter.

I'd fill the bottle with CO2, then fill with beer, then back to the CO2 to purge headspace, and cap. It was real easy to stick the filler down into the headspace and push against the tip to get the CO2 in.

A picture is worth 1000 more words:

btl.jpg


EDIT: I'll definitely use this method again next time I want to bottle something, but will set up a chair rather than put myself into some sort of static deep knee bend. What was I thinking?
 
The counterpressure filler I assembled ~25 years ago could be used to purge.

A typical pressure purge for pharma operations involving flammables was 2x or 3x 15 psig, vented to atmospheric pressure. The math is pretty simple if you assume good mixing, approximately halving the O2 with each 1 atm purge.

Not really sure where the point of diminishing return would be, but purging more than 3x gets pretty tedious, especially if filling a lot of bottles.

Vacuum purging is another option, but I'd want to confirm the bottles were good for full vacuum. I haven't bottled much lately, but tend to steam bottles to sanitize. This displaced the air originally in the bottles with steam, but doesn't deal with air drawn back in upon cooling.
 
Just my experience, but often I come up slightly high on volume and bottle off a six pack or so to bottle condition after filling the (purged) keg to capacity and having a little beer left over.

I don't purge the bottles and these days don't even bother with the bottling wand, just pour down the side of the bottle straight from the spigot. I'm sure in theory I'm supposed to have an oxidized mess, but in reality, after the bottles are carbed up I'll do a side by side taste test, and other than sometimes carbonation level, I can't tell the difference between the bottles and the keg.

I suspect that the bottle conditioning might help clean up the oxygen, but, push comes to shove I don't know for sure. I've never bottled off the keg and then let it sit long enough to see if it had any shelf life without the bottle conditioning w/priming sugar, but that is next on my agenda.

Also I haven't got into NEIPA's yet, so maybe it is different with mega-hoppy styles as well.
 
Of course, as with so many other aspects of brewing, the explanation of why person X has no oxidation problems while person Y does is that person Y is more sensitive to the off-flavors caused by oxidation. I for one seem to be much more sensitive to it than I am to other off-flavors.

EDIT: Not sure why I even scrolled up and re-read this post, but whoah...big mistype there. I meant something like "...ONE explanation of why person X has no oxidation problems while person Y does is that person Y is more sensitive to the off-flavors caused by oxidation."
 
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This came up in another thread recently. IMO, if you are bottle conditioning, that is adding sugar primed beer to the bottles to naturally carbonate, purging is not a good thing to do. The yeast need a little oxygen to do the mini ferment.

If you are bottling from a keg that is already carbonated then purging is a good step.
 
This came up in another thread recently. IMO, if you are bottle conditioning, that is adding sugar primed beer to the bottles to naturally carbonate, purging is not a good thing to do. The yeast need a little oxygen to do the mini ferment.

If you are bottling from a keg that is already carbonated then purging is a good step.

This is what I would like to also understand and find the best way for my own setup. I basically siphon my beer from the fermenting bucket to a bottling bucket with priming sugar and bottle from there with a bottling stick.

Why I am so keen to this whole thing is the fact that I made 5/5 NEIPA some time back and sadly it turned brown.. almost muddy. The taste did not get affected too much, but it looks terrible :( Sad to hand over that kind of beer to my friends, even though taste is superb. I know NEIPAs should be drank very young, but I feel the oxidation coloring happens in a matter of days .. like before the carbonation of the priming sugar is even complete.
 
This is what I would like to also understand and find the best way for my own setup. I basically siphon my beer from the fermenting bucket to a bottling bucket with priming sugar and bottle from there with a bottling stick.

Why I am so keen to this whole thing is the fact that I made 5/5 NEIPA some time back and sadly it turned brown.. almost muddy. The taste did not get affected too much, but it looks terrible :( Sad to hand over that kind of beer to my friends, even though taste is superb. I know NEIPAs should be drank very young, but I feel the oxidation coloring happens in a matter of days .. like before the carbonation of the priming sugar is even complete.

This is just me . I wouldn't be bottling NEIPAs unless I was doing it from a keg for that very day. You can do it but you have to be very up on your game to keep o2 out . I dont know if I'd ever bottle condition a NEipa
 
NEIPAs seem so susceptible to oxidation because of the huge amount of hops that you really need to do closed transfers into co2 purged vessels. I haven't found one I have liked so I haven't even looked into brewing one, but if I did I would only do it if kegging it.
 
This came up in another thread recently. IMO, if you are bottle conditioning, that is adding sugar primed beer to the bottles to naturally carbonate, purging is not a good thing to do. The yeast need a little oxygen to do the mini ferment.

If you are bottling from a keg that is already carbonated then purging is a good step.
Respectfully, this is inaccurate. I'll share a link that explains why but before I do I'll offer my, admittedly, simplistic explanation:
Oxygen is not relevant at all in fermentation. The word you are looking for is respiration - the other metabolic pathway yeast can use, which involves oxygen, but they prefer to ferment if there is sugar available.
There is, however, a roll for oxygen and that is to build cell walls and grow which happens even before fermentation begins and that's the reason we aerate the wort (side note: some yeas manufactures say that aerating wort is unnecessary altogether if you rehydrate the yeast before pitching https://www.lallemandbrewing.com/docs/products/bp/BEST-PRACTICES_REHYDRATION_DIGITAL.pdf )
So in short: any oxygen yeast ever needed was long before bottling.
Fun fact: In theory when there is no sugar but there are ethanol and oxygen available yeast may respire ethanol to produce vinegar (I'm not sure that ever happens when bottle conditioning tho, at least not at any significant level).
Now I would encourage everyone to read the article below a few times.
https://www.morebeer.com/articles/how_yeast_use_oxygen
 
I wonder whether the effectiveness of purging the bottle before filling depends on your method of filling.

Specially, what I had trouble with in the past was filling without creating any bubbles. I am assuming the creation of bubbles means that mixing with the air inside the bottle has taken place (most importantly of course, the O2 in the air). So if you purge the bottle with CO2 then that gas that mixes in will be CO2. No problem. I further assume that initial mixing that occurs, before the end of the wand gets submerged in beer, is the most potentially problematic, not the rising surface of beer coming into contact with air.

But while filling bottles this last time, I figured out how to fill with no bubbles, making me wonder whether the purging I was doing was necessary. And I felt like a fool when I discovered that it was simply a matter of pressing the wand against the center of the bottom of the bottle rather than at the side of the bottom (a "corner" I suppose you could call it).

Maybe those who fill in a way as to not create bubbles while filling (i.e., with very little interaction with gas) don't see any benefit to bottle purging and those who do create bubbles do see a benefit? And of course the more bubbles created the more potential benefit from purging.

Just a thought. And to clarify I'm only talking about purging before filling, not purging the headspace after filling.
 
I wonder whether the effectiveness of purging the bottle before filling depends on your method of filling.

Specially, what I had trouble with in the past was filling without creating any bubbles. I am assuming the creation of bubbles means that mixing with the air inside the bottle has taken place (most importantly of course, the O2 in the air). So if you purge the bottle with CO2 then that gas that mixes in will be CO2. No problem. I further assume that initial mixing that occurs, before the end of the wand gets submerged in beer, is the most potentially problematic, not the rising surface of beer coming into contact with air.

But while filling bottles this last time, I figured out how to fill with no bubbles, making me wonder whether the purging I was doing was necessary. And I felt like a fool when I discovered that it was simply a matter of pressing the wand against the center of the bottom of the bottle rather than at the side of the bottom (a "corner" I suppose you could call it).

Maybe those who fill in a way as to not create bubbles while filling (i.e., with very little interaction with gas) don't see any benefit to bottle purging and those who do create bubbles do see a benefit? And of course the more bubbles created the more potential benefit from purging.

Just a thought. And to clarify I'm only talking about purging before filling, not purging the headspace after filling.
It appears that purging the whole bottle probably makes no difference (it did not made any difference in the experiment Tauro did; see link in my post above)
What I think is that bulk of oxidation comes from long term exposure to oxygen in the headspace, especially since bottle is under pressure form carbonation.
You could get some oxygen if you are splashing when filling your bottle but since you are using the wand, like you have explained, I guess the amount of oxygen that gets in while filling the bottle is negligible.
I really doubt that oxygen transfers from atmosphere to beer, under normal pressure, at any rate that is significant to us( the time beer is in the bottling bucket and while it's being bottled)
If someone has some scientific way to prove or disprove any of what I said please do.
 
(side note: some yeas manufactures say that aerating wort is unnecessary altogether if you rehydrate the yeast before pitching https://www.lallemandbrewing.com/docs/products/bp/BEST-PRACTICES_REHYDRATION_DIGITAL.pdf )
So in short: any oxygen yeast ever needed was long before bottling.
Fun fact: In theory when there is no sugar but there are ethanol and oxygen available yeast may respire ethanol to produce vinegar (I'm not sure that ever happens when bottle conditioning tho, at least not at any significant level).
Now I would encourage everyone to read the article below a few times.
https://www.morebeer.com/articles/how_yeast_use_oxygen

Maybe... But there is now disagreement or there are differences in the way that dry yeast labs engineer their yeasts. Fermentis now recommends that you DO NOT rehydrate their yeasts. They also say that what is in the coatings on the yeast cells eliminate the need for aeration.
 
To me bottle purging is an exercise in degree of benefit. I have always bottled from a bottling bucket with a wand into bottles without any purging. Even my IPAs do not darken or go card board on me. I have never tasted anything that is described as oxidation flavor in my beers.

So for me it is not something that I am concerned with and I save on co2 and time.

Could more careful steps in eliminating oxygen help my beers? Probably. I would expect sharper hop flavor and aroma first, long before any oxidation flavors.
 
I wonder whether the effectiveness of purging the bottle before filling depends on your method of filling.

Specially, what I had trouble with in the past was filling without creating any bubbles. I am assuming the creation of bubbles means that mixing with the air inside the bottle has taken place (most importantly of course, the O2 in the air). So if you purge the bottle with CO2 then that gas that mixes in will be CO2. No problem. I further assume that initial mixing that occurs, before the end of the wand gets submerged in beer, is the most potentially problematic, not the rising surface of beer coming into contact with air.

But while filling bottles this last time, I figured out how to fill with no bubbles, making me wonder whether the purging I was doing was necessary. And I felt like a fool when I discovered that it was simply a matter of pressing the wand against the center of the bottom of the bottle rather than at the side of the bottom (a "corner" I suppose you could call it).

Maybe those who fill in a way as to not create bubbles while filling (i.e., with very little interaction with gas) don't see any benefit to bottle purging and those who do create bubbles do see a benefit? And of course the more bubbles created the more potential benefit from purging.

Just a thought. And to clarify I'm only talking about purging before filling, not purging the headspace after filling.

I suspect that the bubbles you are seeing is co2 coming out of solution of the partially carbonated beer that you are bottling and not oxygen. The fermentation process creates co2.

I have not noticed or even tried to prevent the bubbles by where I depress the wand. I use Starsan to sanitize my bottles and that bubbles up. I rely on the bubbles to show me when I am about full on the bottle. That way less is spilled, meaning I may get an extra bottle or two out of the batch.
 
Maybe... But there is now disagreement or there are differences in the way that dry yeast labs engineer their yeasts. Fermentis now recommends that you DO NOT rehydrate their yeasts. They also say that what is in the coatings on the yeast cells eliminate the need for aeration.
Yeah, I guess it's the way they "engineer" their yeast. Whatever it is I'm usually inclined to follow the procedure on the package.
But all this is not important for the discussion going on here. Where I was actually going with this is just to reaffirm the fact that oxygen plays no role in fermentation itself, thus it will not be processed during "mini fermentation" while the beer is carbonating.
 
Yeah, I guess it's the way they "engineer" their yeast. Whatever it is I'm usually inclined to follow the procedure on the package.
But all this is not important for the discussion going on here. Where I was actually going with this is just to reaffirm the fact that oxygen plays no role in fermentation itself, thus it will not be processed during "mini fermentation" while the beer is carbonating.

Even with the links, I am not sure I agree. The yeast is old and may have to reproduce to carbonate the beer, then they will consume that small amount of oxygen. Remember we are talking of about 1 cubic inch of air that is only 20.95% oxygen.
 
Even with the links, I am not sure I agree. The yeast is old and may have to reproduce to carbonate the beer, then they will consume that small amount of oxygen. Remember we are talking of about 1 cubic inch of air that is only 20.95% oxygen.
You may have a point about reproduction there, but I would assume there are not that many yeast in the bottle and they are not reproducing as much under those conditions, and what is "only 1 cubic inch” for us is huge for them. Besides I feel there is enough evidence for me to accept that headspace oxygen is causing oxidation which is especially apparent in more hoppy beers.

Now just to be clear here, vast majority of people are producing great beers without "purging" the head space, myself included (but will do a few experiments on my own setup and if there are significant improvements I will start to purge).

I feel that this, like many other things in this hobby, is not something that is necessary, you certainly don’t have to do it.

BUT for some folks this is not only about making beer but about learning more along the way, testing, trying to improve their processes, even minimally. For them this is huge part of the fun

And I'm not saying either is better, to each their own.
 
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