Limiting oxidation: effect of purging headspace O2 in a bottle conditioned IPA

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Taket_al_Tauro

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Hi,

I did a very small „exbeeriment“ with my latest IPA batch. This is nothing new under the sun, really… at least not for the more experienced folks around here. Still, the results were quite eye opening to me, so I figured I would share them here.

Long story short: purging O2 out of the bottle headspace helped significantly in preserving colour and hop character in my bottle conditioned IPA. In contrast, an additional purge of the bottle prior to filling did not bring any noticeable benefits.


Now the full story, for those who might be interested in the details (warning, it is a long post!):

On a quest to improve the quality of my hoppy beers, I recently became aware that post-fermentation oxidation is a real issue in these styles. If not managed properly, this seems to be one of the key factors contributing to rapid hop fade and staling in hop forward beers. Of course, I also read that switching to kegging is by far the best way to control this issue, since it allows closed transfers, easy purging with CO2, and so on. However, I’m not able to make the move to kegging just yet (although I’d love to, of course). So for the time being, I’ll have to make it work with my poor-man bottling setup. I believe I had been taking the necessary basic steps to reduce oxidation prior to and during bottling, such as avoiding unnecessary openings of the fermenter, transferring with minimal splashing, and filling with a bottling wand. Yet from what I’ve read, these simple measures may not be enough for a really hoppy beer. So for this latest IPA batch, not having any CO2 at hand, I bought a can of wine-preserving gas (brand name “Private Preserve”) to do some experimenting with purging bottles. It is a mixture of N2, Argon and CO2 ant it should do the same job as pure CO2. By the way, the beer was a “regular” AIPA of the west-coastish type, not a NEIPA.

The experiment consisted of three variants:

- Complete-purge: I purged both the empty bottle prior to filling, as well as the headspace after filling.

- Headspace-purge: I only purged the headspace after filling.

- No-purge: I didn’t purge anything, as I would usually do in all my previous batches.

I did 4 replicates for each variant (= 4 x 12 oz. flip-top bottles for each variant). I filled these 12 bottles approximately in the middle of the filling process. I did mix up the variants during filling, to avoid potential biases due to the time of filling and the specific part of the batch being filled at that moment. Afterwards I let them condition at 73-75 F for approx. one week, and then stored them in a basement at approx. 60-63 F.

I started doing the first side-by-side compares between variants about 5 weeks after bottling. The beer was hitting its prime at that point, and differences between purged vs. non-purged variants were already fairly noticeable. I did the last comparison approximately 3.5 months post bottling, and here is a picture of this last comparison (all three variants):

P1010266_NEW_zps5qwxi9ua.jpg.html



You can see how the “No-purge” variant is evidently darker. The differences in aroma/taste are not as dramatic as the colour would suggest, but they are noticeable. I found the overall hop character to be somehow duller in “No-purge” as compared to the two purged variants. Actually, I wouldn’t call “No-purge” a bad hoppy beer, by any means (for my taste at least). Yet in such a direct comparison, the two purged variants win, and there is no doubt about that. The “No-purge” version has also developed a slightly sweeter, maltier taste and some kind of weird spicy note in the aftertaste which I am not able to classify (maybe somehow medicinal or metallic?...but it is quite subtle). Anyway, in summary, I found that the two purged variants to come across as fresher, brighter, and also noticeably drier and crisper.

Now the second, and at least for me most interesting result: there is NO noticeable difference between the two purged variants, neither in color nor in aroma/taste. This means that purging the bottle prior to filling did not bring any additional benefit. By the way, these observations were consistent over all four replicates and the different sampling time points.

I conclude that, for my own bottle-conditioning process, purging the headspace after filling is enough to reduce oxidation of hop compounds in a significant way, and that an additional purge of the bottle prior to filling is an unnecessary waste of time and money. The air remaining in the bottle headspace is the real culprit here. By the same logic, I think I’ll not bother purging the bottling bucket before transferring the beer onto it, and purging the headspace of the fermenter and of the bottling bucket during and after the transfer.

So how can we explain these results? We are talking about bottle-conditioned beer. Probably, the active yeast does indeed take care of most of the O2 being introduced during transferring and bottling (provided O2-pickup stays within a reasonably low range). However, the O2 in the headspace sits there, trapped in the bottle over a long period, and it will gradually diffuse into the beer. It will continue diffusing also when the yeast is no longer active, causing significant oxidation to hop aroma compounds. Of course, this theory is not my own invention: I read it multiple times on forums. Yet I couldn’t find a consensus. Some people seem to argue that O2 pickup during transfers is the main culprit, and headspace-O2 is a secondary concern. Others even claim that yeast will consume the headspace O2 near completely during bottle conditioning, which is a myth as far as this small experiment can tell (as well as a couple other very similar experiments/experiences I came across on the web).

Now why do pro-brewers and more than one kegging homebrewer bother to purge ALL vessels during transfers, ALL kegs, bottles, headspaces and even tubing? I guess that is because they are packaging finished beer in most cases. Finished in the sense that it has completed fermentation and it won’t go through a secondary fermentation based on priming sugar. The beer was probably cold-crashed too, so not only there is less yeast in there, but above all, the yeast is not active. I can well believe that in such scenarios, oxidation happening during transfers is a real issue. I guess it is much less of an issue for the bottle-conditioning folks.

In conclusion, is it even worth to bother purging the bottle headspaces? I found evident differences in colour, but the differences in aroma and taste were more subtle. I guess I’ll continue doing this but just for my really hoppy beers. It might be worth it if you want to be anal or if you are sending the beers to a comp! ;-)

I’m eager to hear your thoughts on this subject J

Cheers!
 
I use flip-top bottles, and the "Private Preserve" can I used to do this experiment comes with a thin straw. After filling, I lifted the cap just a bit to let the straw in, briefly flushed the headspace with gas, and then closed it immediately after.
 
Very interesting write up and exBeeriment. Thanks for putting it out there. Your results line up with what I have seen as well. I personally am biased towards not doing any purging or adding oxygen. Even though an incredible amount of technology goes into my homebrew outside of my home, once it get here, I want to pretend that it’s my spoons and bottle brush that are making all of the wonder, so tanks of preservation gas are not on my shopping list. Oxygen absorption cap might help though and still allow me to believe that I’m brewing in the olden days.
 
Hi,

I did a very small „exbeeriment“ with my latest IPA batch. This is nothing new under the sun, really… at least not for the more experienced folks around here. Still, the results were quite eye opening to me, so I figured I would share them here.

Long story short: purging O2 out of the bottle headspace helped significantly in preserving colour and hop character in my bottle conditioned IPA. In contrast, an additional purge of the bottle prior to filling did not bring any noticeable benefits.


Now the full story, for those who might be interested in the details (warning, it is a long post!):

On a quest to improve the quality of my hoppy beers, I recently became aware that post-fermentation oxidation is a real issue in these styles. If not managed properly, this seems to be one of the key factors contributing to rapid hop fade and staling in hop forward beers. Of course, I also read that switching to kegging is by far the best way to control this issue, since it allows closed transfers, easy purging with CO2, and so on. However, I’m not able to make the move to kegging just yet (although I’d love to, of course). So for the time being, I’ll have to make it work with my poor-man bottling setup. I believe I had been taking the necessary basic steps to reduce oxidation prior to and during bottling, such as avoiding unnecessary openings of the fermenter, transferring with minimal splashing, and filling with a bottling wand. Yet from what I’ve read, these simple measures may not be enough for a really hoppy beer. So for this latest IPA batch, not having any CO2 at hand, I bought a can of wine-preserving gas (brand name “Private Preserve”) to do some experimenting with purging bottles. It is a mixture of N2, Argon and CO2 ant it should do the same job as pure CO2. By the way, the beer was a “regular” AIPA of the west-coastish type, not a NEIPA.

The experiment consisted of three variants:

- Complete-purge: I purged both the empty bottle prior to filling, as well as the headspace after filling.

- Headspace-purge: I only purged the headspace after filling.

- No-purge: I didn’t purge anything, as I would usually do in all my previous batches.

I did 4 replicates for each variant (= 4 x 12 oz. flip-top bottles for each variant). I filled these 12 bottles approximately in the middle of the filling process. I did mix up the variants during filling, to avoid potential biases due to the time of filling and the specific part of the batch being filled at that moment. Afterwards I let them condition at 73-75 F for approx. one week, and then stored them in a basement at approx. 60-63 F.

I started doing the first side-by-side compares between variants about 5 weeks after bottling. The beer was hitting its prime at that point, and differences between purged vs. non-purged variants were already fairly noticeable. I did the last comparison approximately 3.5 months post bottling, and here is a picture of this last comparison (all three variants):

P1010266_NEW_zps5qwxi9ua.jpg.html



You can see how the “No-purge” variant is evidently darker. The differences in aroma/taste are not as dramatic as the colour would suggest, but they are noticeable. I found the overall hop character to be somehow duller in “No-purge” as compared to the two purged variants. Actually, I wouldn’t call “No-purge” a bad hoppy beer, by any means (for my taste at least). Yet in such a direct comparison, the two purged variants win, and there is no doubt about that. The “No-purge” version has also developed a slightly sweeter, maltier taste and some kind of weird spicy note in the aftertaste which I am not able to classify (maybe somehow medicinal or metallic?...but it is quite subtle). Anyway, in summary, I found that the two purged variants to come across as fresher, brighter, and also noticeably drier and crisper.

Now the second, and at least for me most interesting result: there is NO noticeable difference between the two purged variants, neither in color nor in aroma/taste. This means that purging the bottle prior to filling did not bring any additional benefit. By the way, these observations were consistent over all four replicates and the different sampling time points.

I conclude that, for my own bottle-conditioning process, purging the headspace after filling is enough to reduce oxidation of hop compounds in a significant way, and that an additional purge of the bottle prior to filling is an unnecessary waste of time and money. The air remaining in the bottle headspace is the real culprit here. By the same logic, I think I’ll not bother purging the bottling bucket before transferring the beer onto it, and purging the headspace of the fermenter and of the bottling bucket during and after the transfer.

So how can we explain these results? We are talking about bottle-conditioned beer. Probably, the active yeast does indeed take care of most of the O2 being introduced during transferring and bottling (provided O2-pickup stays within a reasonably low range). However, the O2 in the headspace sits there, trapped in the bottle over a long period, and it will gradually diffuse into the beer. It will continue diffusing also when the yeast is no longer active, causing significant oxidation to hop aroma compounds. Of course, this theory is not my own invention: I read it multiple times on forums. Yet I couldn’t find a consensus. Some people seem to argue that O2 pickup during transfers is the main culprit, and headspace-O2 is a secondary concern. Others even claim that yeast will consume the headspace O2 near completely during bottle conditioning, which is a myth as far as this small experiment can tell (as well as a couple other very similar experiments/experiences I came across on the web).

Now why do pro-brewers and more than one kegging homebrewer bother to purge ALL vessels during transfers, ALL kegs, bottles, headspaces and even tubing? I guess that is because they are packaging finished beer in most cases. Finished in the sense that it has completed fermentation and it won’t go through a secondary fermentation based on priming sugar. The beer was probably cold-crashed too, so not only there is less yeast in there, but above all, the yeast is not active. I can well believe that in such scenarios, oxidation happening during transfers is a real issue. I guess it is much less of an issue for the bottle-conditioning folks.

In conclusion, is it even worth to bother purging the bottle headspaces? I found evident differences in colour, but the differences in aroma and taste were more subtle. I guess I’ll continue doing this but just for my really hoppy beers. It might be worth it if you want to be anal or if you are sending the beers to a comp! ;-)

I’m eager to hear your thoughts on this subject J

Cheers!

I know it's 15 months old thread but I'll still chance it.

How many times/ how long do you purge the head space?

By the way amazing info there, I don't know how this did not get more attention.
 
I know it's 15 months old thread but I'll still chance it.

How many times/ how long do you purge the head space?

By the way amazing info there, I don't know how this did not get more attention.

Hi, thanks for your feedback and glad you found this small experiment interesting.
I just purge a bottle headspace once with a very brief burst of gas, let's say half a second or something like that .

In the meantime I tried the trick on a few more hoppy beers, and always left a few bottles unpurged for comparison. It confirmed the observations I posted here. The effect on preserving an overall lighter (and brighter) beer color is striking. Less so with respect to flavour/aroma. Although, for very hop-forward beers like IPAs, I could still definitely perceive a difference.

Now I would like to do some more experimenting with very high bottle fills (I.e. leaving very little headspace) as compared to purging with gas. I started doing that on my last batch, but I probably did not go high enough with the fill... there was still a remarkable difference in color compared to the gas-purged variant... this despite a very little headspace of just about 1-1,5 cm.
 
Hi, thanks for your feedback and glad you found this small experiment interesting.
I just purge a bottle headspace once with a very brief burst of gas, let's say half a second or something like that .

In the meantime I tried the trick on a few more hoppy beers, and always left a few bottles unpurged for comparison. It confirmed the observations I posted here. The effect on preserving an overall lighter (and brighter) beer color is striking. Less so with respect to flavour/aroma. Although, for very hop-forward beers like IPAs, I could still definitely perceive a difference.

Now I would like to do some more experimenting with very high bottle fills (I.e. leaving very little headspace) as compared to purging with gas. I started doing that on my last batch, but I probably did not go high enough with the fill... there was still a remarkable difference in color compared to the gas-purged variant... this despite a very little headspace of just about 1-1,5 cm.

Thanks for the reply. As I'm brewing small batches only(2 gallons) this is a great option for me as there are not too many bottles to go through.

Please keep us posted on you experiment with higher fill ups.
 
Thanks for the reply. As I'm brewing small batches only(2 gallons) this is a great option for me as there are not too many bottles to go through.

Please keep us posted on you experiment with higher fill ups.

You probably will do it anyway, but I advise you nonetheless to leave at least one or a few bottles unpurged for comparison. You'll need to find out if this is worth the extra cost and effort for your specific situation.

Yes I will try to keep you posted with results from my "high fill" vs. "headspace purge" small trials.
But next time I'll brew a really hop forward beer will probably be eary spring 2020...

Please do post also your findings...I'll be interested to hear how the headpace purge performs with other people's systems/processes.
 
You probably will do it anyway, but I advise you nonetheless to leave at least one or a few bottles unpurged for comparison. You'll need to find out if this is worth the extra cost and effort for your specific situation.

Yes I will try to keep you posted with results from my "high fill" vs. "headspace purge" small trials.
But next time I'll brew a really hop forward beer will probably be eary spring 2020...

Please do post also your findings...I'll be interested to hear how the headpace purge performs with other people's systems/processes.
Yes, that's what I was planing. Although I believe your findings 100% I would like to see it for myself. I plan to brew NEIPA in January/February that's why I'm researching this now and that's how I came across this thread. I will make sure to post some pictures as well once I try this method.
I'm thinking now, I should probably do what you did and try no purge/purge head space/purge whole bottle+head space, if nothing else to confirm your test.
 
I plan to brew NEIPA in January/February that's why I'm researching this now and that's how I came across this thread.

I think I mentioned it in the main post already, but I would still point out that, up to now, I only brewed "west-coastish" style IPAs. I did not attempt a NEIPA yet because I was too scared about oxidation, not having a kegging setup and all… but after those positive results, I feel bold enough to try my luck with a bottle conditioned NEIPA next spring… despite all people’s warnings against bottling this style.

I should also add that my hopping rates in those last IPAs I made were well up in NEIPA territory (13-14 oz total hops scaled to a 5 gal batch). Only things different were the yeast strain (i.e. a clean ale yeast, WY 1450, as opposed to your typical NEIPA yeasts), the fact I did not use any adjuncts such as oats, and maybe the water profile (higher SO4 than Cl)… So I see no reasons why this should not work for a NEIPA…but I could be terribly wrong here.
 
This is such an interesting thread. Thanks for sharing your findings and I am looking forward to hearing about the no head space experiments.

Found this, did not even know that such a thing existed. Pure argon in a spray can, how convenient!

https://www.amazon.co.uk/Preservint...=2025&creative=165953&creativeASIN=B07MQFTKPN
Yeah I saw that too. I hate that it's gonna cost me 7 more quid to ship it to Ireland and I can't find it in Dublin (you can't find anything in this village)
 
I think I mentioned it in the main post already, but I would still point out that, up to now, I only brewed "west-coastish" style IPAs. I did not attempt a NEIPA yet because I was too scared about oxidation, not having a kegging setup and all… but after those positive results, I feel bold enough to try my luck with a bottle conditioned NEIPA next spring… despite all people’s warnings against bottling this style.

I should also add that my hopping rates in those last IPAs I made were well up in NEIPA territory (13-14 oz total hops scaled to a 5 gal batch). Only things different were the yeast strain (i.e. a clean ale yeast, WY 1450, as opposed to your typical NEIPA yeasts), the fact I did not use any adjuncts such as oats, and maybe the water profile (higher SO4 than Cl)… So I see no reasons why this should not work for a NEIPA…but I could be terribly wrong here.
Well, there's only one way to find out.
As I said I make small batches only so it wouldn't be too bad if I have ruined one batch. And I am sure it wouldn't be completely ruined too, i guess it would still be drinkable but not perfect/the way you want it to be.
I agree, I wouldn't say yeast and water chemistry have much to do with oxidation, it's mainly hops, but what do I know.
As I said, I plan to do NEIPA in the next couple of months and will repeat your experiment on it and post the pics here.
It would be great if someone else would do it too so we have examples from multiple different setups.
While we're on the topic I'm looking for a good NEIPA recipe so if anyone has a good one to share please do.
 
As I said I make small batches only so it wouldn't be too bad if I have ruined one batch.

I did just upgrade my system (I cannot brew that often unfortunately, so let's at least increase batch size), and I'll be fool enough to try my first bottle conditioned NEIPA with a 15 gallon batch ;-)
I plan a split-batch to test two different yeasts.

As I said, I plan to do NEIPA in the next couple of months and will repeat your experiment on it and post the pics here.

Please do, thanks in advance! It will be very interesting, especially on a NEIPA.

While we're on the topic I'm looking for a good NEIPA recipe so if anyone has a good one to share please do.

You surely know about the main NEIPA thread on here:
https://www.homebrewtalk.com/forum/threads/northeast-style-ipa.568046/

Plenty of amazing process info (as well as recipes) on how to brew good NEIPAs there...
 
After seeing this thread last year, and especially post #5, I ordered a couple cans of the wine preserver from Amazon. The first two batches I used it on every bottle to purge/fill the headspaces. But, that way 1 can only lasted two batches. So now, I only use it on the bottles I plan on storing for long-term comparisons, and the ones I plan on sending to competitions. Plus I'm using the O2 scavenging caps. Does it make a difference? I'm not sure, but with my NEIPAs and lagers, I believe it does.If I find some old treated vs. nontreated bottles to compare, I'll post pics.
 
The first two batches I used it on every bottle to purge/fill the headspaces. But, that way 1 can only lasted two batches. So now, I only use it on the bottles I plan on storing for long-term comparisons, and the ones I plan on sending to competitions.

Yeah, I agree that the stuff is still probably not cheap enough for high throughput...

The handy thing about these cans is that you can hold and operate the can with one hand, and hold the bottle cap with the other. This allows you to only lift the cap a bit and close immediately after the purge.
I do not see the same level of ease when using a soda stream for example, as a poster above suggested.
Although I do have one and I should maybe try for myself once...

The best thing would probably be a small CO2 tank and something like a beer gun...but at that point, better make the move to kegging...
 
Yeah, I agree that the stuff is still probably not cheap enough for high throughput...

The handy thing about these cans is that you can hold and operate the can with one hand, and hold the bottle cap with the other. This allows you to only lift the cap a bit and close immediately after the purge.
I do not see the same level of ease when using a soda stream for example, as a poster above suggested.
Although I do have one and I should maybe try for myself once...

The best thing would probably be a small CO2 tank and something like a beer gun...but at that point, better make the move to kegging...
Or maybe one of these with some kind of nozzle fitted?
I came across that idea on this or some other forum, can't remember now.
 

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And just to be technically correct here (as someone said "the best kind of correct) we are not really talking about O2 purging here. As other, more knowledgeable people on other threads and forums, pointed out: to really purge O2 you would have to have a liquid pushed out, and replaced, by CO2(or other gas like Argon). I know they were talking about purging kegs and that's impossible to do that for head space in the bottle, but it's just the matter of time before someone comes on this thread and drives this discussion sideways by explaining this to everyone. So I just wanted to get this out of the way so we can continue talking about what's important to us here.
Yes, we are not purging O2 from the head space but rather mixing O2 and CO2 (as gas laws suggest). Hopefully the O2 in the mix is negligible but certainly is less than it used to be.
And in the end, all of this doesn't matter if the results of "purging" the head space result in clearly better beer as Taket_al_Tauro's example has showed.
Sorry for the long and may be unnecessary post but, as I said, I'm just trying to bury this discussion before it even starts.
 
And just to be technically correct here (as someone said "the best kind of correct) we are not really talking about O2 purging here. As other, more knowledgeable people on other threads and forums, pointed out: to really purge O2 you would have to have a liquid pushed out, and replaced, by CO2(or other gas like Argon). I know they were talking about purging kegs and that's impossible to do that for head space in the bottle, but it's just the matter of time before someone comes on this thread and drives this discussion sideways by explaining this to everyone. So I just wanted to get this out of the way so we can continue talking about what's important to us here.
Yes, we are not purging O2 from the head space but rather mixing O2 and CO2 (as gas laws suggest). Hopefully the O2 in the mix is negligible but certainly is less than it used to be.
And in the end, all of this doesn't matter if the results of "purging" the head space result in clearly better beer as Taket_al_Tauro's example has showed.
Sorry for the long and may be unnecessary post but, as I said, I'm just trying to bury this discussion before it even starts.
I think the above mentioned idea to purge it into the beer so that foam is created is pretty close to really purging the head space as the foam bubbles shouldn't contain any air but only the purging gas.
 
I think the above mentioned idea to purge it into the beer so that foam is created is pretty close to really purging the head space as the foam bubbles shouldn't contain any air but only the purging gas.
Yeah, that's surely worth a try.
But as I said it doesn't matter how we do it as long as the results are there.
All I did in a previous post is tried to stop a debate before it even starts because I saw on other forums how heated and unnecessary debates about this can be.
 
I think the above mentioned idea to purge it into the beer so that foam is created is pretty close to really purging the head space as the foam bubbles shouldn't contain any air but only the purging gas.

Interesting idea. I'll try this as well on my next hoppy batch and compare to my "by now s.o.p" of displacing the headspace air ( or most of it, to be correct ).
It may be a bit tricky to find the right balance between not being able to fill the complete headspace with bubbles and creating a mess... but as always there is only one way to find out.
 
Interesting idea. I'll try this as well on my next hoppy batch and compare to my "by now s.o.p" of displacing the headspace air ( or most of it, to be correct ).
It may be a bit tricky to find the right balance between not being able to fill the complete headspace with bubbles and creating a mess... but as always there is only one way to find out.
I'm about to move houses (and countries), so I'm a bit or if the brewing game but next time I'll be brewing something, I'll be definitely trying this!
 
Interesting idea. I'll try this as well on my next hoppy batch and compare to my "by now s.o.p" of displacing the headspace air ( or most of it, to be correct ).
It may be a bit tricky to find the right balance between not being able to fill the complete headspace with bubbles and creating a mess... but as always there is only one way to find out.
One great thing is also that you have a visual measure of how much gas is really needed so the bottle will hopefully last longer.
 
One great thing is also that you have a visual measure of how much gas is really needed so the bottle will hopefully last longer.

Yeah, although I find it hard to believe I would use less gas compared to my current practice. I really just try to flush the headspace as briefly as possible.

Now this idea brings something back to my mind: there was one guy in another forum who advocated the practice of filling directly from the spigot, without a bottling wand. This would make the beer foam up in the bottle (even though not carbonated), and he would then be able to cap on foam.
Obviously this guy had a hard time on that thread, because this practice goes against all conventional wisdom about trying to reduce air contact as much as possible.
But maybe there is something to it... if it works, that would be a hell of a cheap and straightforward method. One more thing to try!
From my few small experiments so-far I gained the impression that it is not the brief air contact during transfers that oxidizes the beer most, but much more the prolonged contact with even the tiny amount of air in a bottle headspace. As always I'm talking about bottle conditioned beer here, and working with active yeast as your friend. That might be completely different for transfers implying cold and finished beer.
 
... as a further "data point": I took on the habit of always labeling the last 5-6 bottles I fill. Like 6-5-4-3-2-1. Mostly to avoid giving them away as I feared they would be somehow oxidized. But it turned out to be an interesting small experiment in its own right.
For my last two IPA batches I did not notice any signs of oxidation from bottles 5/6 down to 2. Maybe only the very last bottle did show some darker hue and possibly also the taste was not quite up there with the rest (did not do side-by-dide comparisons hiere). But for me, the others were completely OK ant not a bit different than the ones that were filled before.
I should add that in my last IPA batch I had dry-hop matter drift over to my bottling bucket, and filling those last bottles was a pain, with the wand clogging repeatedly. I had air bubbling through the wand, had to move several times the bottling bucket back and forth, with very little beer left in it, and had to finish filling without the wand... so everything not really optimal from a LODO perspective. Still that did not seem to negatively impact those bottles.
 
Yeah, although I find it hard to believe I would use less gas compared to my current practice. I really just try to flush the headspace as briefly as possible.

Now this idea brings something back to my mind: there was one guy in another forum who advocated the practice of filling directly from the spigot, without a bottling wand. This would make the beer foam up in the bottle (even though not carbonated), and he would then be able to cap on foam.
Obviously this guy had a hard time on that thread, because this practice goes against all conventional wisdom about trying to reduce air contact as much as possible.
But maybe there is something to it... if it works, that would be a hell of a cheap and straightforward method. One more thing to try!
From my few small experiments so-far I gained the impression that it is not the brief air contact during transfers that oxidizes the beer most, but much more the prolonged contact with even the tiny amount of air in a bottle headspace. As always I'm talking about bottle conditioned beer here, and working with active yeast as your friend. That might be completely different for transfers implying cold and finished beer.
I'm not saying I know anything but will offer my opinion on this anyways :) . I feel that bottling straight from the spigot (especially if you cold crash and don't bring the temperature up) would introduce some oxygen to the beer. I feel that splashing of beer against the bottom of the bottle would cause the oxygen to dissolve in beer quicker. On the other hand, filling the bottle(or bottling bucket, or secondary) without splashing would mean that O2 would need to get into the beer from the atmosphere, under atmospheric pressure, and I recon that is a very slow process, certainly not one that is measured in seconds or minutes (probably not even hours).
So I agree with your statement that the main culprit of beer oxidation would be prolonged(days, weeks, months) contact with O2 in head space couples with above atmospherics pressure in the bottle. Brief contact with O2 from atmosphere is surely negligible, unfortunately I don't feel that splashing helps but I'm not sure how much it would contribute to oxidation.
Again I'm not claiming any expertise on this and would love if someone would correct my assumptions with evidence or scientific data(hopefully the kind of data that my simple brain can understand)
 
... as a further "data point": I took on the habit of always labeling the last 5-6 bottles I fill. Like 6-5-4-3-2-1. Mostly to avoid giving them away as I feared they would be somehow oxidized. But it turned out to be an interesting small experiment in its own right.
For my last two IPA batches I did not notice any signs of oxidation from bottles 5/6 down to 2. Maybe only the very last bottle did show some darker hue and possibly also the taste was not quite up there with the rest (did not do side-by-dide comparisons hiere). But for me, the others were completely OK ant not a bit different than the ones that were filled before.
I should add that in my last IPA batch I had dry-hop matter drift over to my bottling bucket, and filling those last bottles was a pain, with the wand clogging repeatedly. I had air bubbling through the wand, had to move several times the bottling bucket back and forth, with very little beer left in it, and had to finish filling without the wand... so everything not really optimal from a LODO perspective. Still that did not seem to negatively impact those bottles.
Thank you for this. It only further proves that the biggest concern is head space oxygen, which makes sense really as it is the oxygen beer is the most in contact with. I'm thinking now....if brief contact with oxygen from the atmosphere would really oxidase beer imagine what would prolonged contact with head space oxygen under pressure would do.
 
. I feel that bottling straight from the spigot (especially if you cold crash and don't bring the temperature up) would introduce some oxygen to the beer.

Yes, I should also add that I do not cold crash. Mainly because I do not have the possibility to do so. But I am also more and more convinced that it would not be a good idea to cold crash combined with my current very basic bottling practice.
Of course, once you can cold-crash under postive CO2 pressure and then perform closed transfers with CO2, things may start looking completely different.

I usually dry hop in my basement at around 15 to 17 °C, then move the fermenters up in the living room the night before bottling.
So when I bottle the beer will be at around 20 °C usually.

That being said, I'm definitely not giving up on the bottling wand yet. I also become heart ache when I see beer splashing... but I would like to further explore the idea of trying to cap on foam.
 
Awesome thread!! thumbs up! Has anyone used any "additions" to combat the oxidation? Example vitamin C?
 
Awesome thread!! thumbs up! Has anyone used any "additions" to combat the oxidation? Example vitamin C?
That would be beyond my knowledge level.
If you have some links please do share.
I have ordered can of "Private preserve" yesterday. It's, apparently, a mix of argon nitrogen and CO2 (I tough it was argon only) so we will see how that works for me soon. I hope I get similar results to Taket_al_Tauro.
 
Yeah, although I find it hard to believe I would use less gas compared to my current practice. I really just try to flush the headspace as briefly as possible.

Now this idea brings something back to my mind: there was one guy in another forum who advocated the practice of filling directly from the spigot, without a bottling wand. This would make the beer foam up in the bottle (even though not carbonated), and he would then be able to cap on foam.
Obviously this guy had a hard time on that thread, because this practice goes against all conventional wisdom about trying to reduce air contact as much as possible.
But maybe there is something to it... if it works, that would be a hell of a cheap and straightforward method. One more thing to try!
From my few small experiments so-far I gained the impression that it is not the brief air contact during transfers that oxidizes the beer most, but much more the prolonged contact with even the tiny amount of air in a bottle headspace. As always I'm talking about bottle conditioned beer here, and working with active yeast as your friend. That might be completely different for transfers implying cold and finished beer.
Although not being that guy, this is actually what I did. But I guess the foam is, at least partially, consisting of normal air, so it might not be the best idea.

However, it would be possible to fill the bottle up until the end, meaning 100% full. If you could check if this version would also do the trick, this would be awesome.
 
Although not being that guy, this is actually what I did. But I guess the foam is, at least partially, consisting of normal air, so it might not be the best idea.

I'm not sure I understood what you mean here: Did you actually try this yourself already?

However, it would be possible to fill the bottle up until the end, meaning 100% full. If you could check if this version would also do the trick, this would be awesome.

100% full is not going to work properly IME. I tried this already. But I found out the liquid inside would expand a bit during the bottle conditioning process. I don't know the science behind this. But I could imagine that the products of fermentation (CO2 and ethanol) require somehow more space than the source compound (sugar). I can rule out thermal expansion, since the bottles did not warm up any more than the temperature they were subjected to during the first days of conditioning. On the opposite, they were stored in a cooler basement after one week of carbonating at room temps.
Anyhow I had some beer pushing through the gasket and out of the bottle. And I did not even fill that bottle 100%, but left like a 0.5 cm headspace.
The optimum would probably be to fill as high as possible, but still not too high to avoid such problems at best, and bottle bombs at worst.
That probably still requires some more experience in order to nail it correctly. As said before, I tried a higher fill on another bottle, but that wasn't high enough and I still got some darkening (oxidation).
 
I'm not sure I understood what you mean here: Did you actually try this yourself already?



100% full is not going to work properly IME. I tried this already. But I found out the liquid inside would expand a bit during the bottle conditioning process. I don't know the science behind this. But I could imagine that the products of fermentation (CO2 and ethanol) require somehow more space than the source compound (sugar). I can rule out thermal expansion, since the bottles did not warm up any more than the temperature they were subjected to during the first days of conditioning. On the opposite, they were stored in a cooler basement after one week of carbonating at room temps.
Anyhow I had some beer pushing through the gasket and out of the bottle. And I did not even fill that bottle 100%, but left like a 0.5 cm headspace.
The optimum would probably be to fill as high as possible, but still not too high to avoid such problems at best, and bottle bombs at worst.
That probably still requires some more experience in order to nail it correctly. As said before, I tried a higher fill on another bottle, but that wasn't high enough and I still got some darkening (oxidation).

I was basically just bottling directly from the spigot, but did not do any other testings. It worked better than expected but still wasn't the best for hoppy beers, indicating that the headspace is the real culprit, not the oxygen exposure during the bottling process... But we knew that already.
 
I’ll be bottling a batch on Friday and I am going to test the ideas that came up on this thread during the last days. I actually did not plan any specific “experiments” on this one, because it is not what I would consider a very hop forward beer by modern standards. It’s kind of a hybrid between a Belgian beer and an APA with “only” about 1.6 oz of dry hops (scaled to a 5 gal batch).

Still, since this thread has been revived (thank you guys), I’m eager to test new ideas, while preparing for my final boss (the NEIPA planned for next spring).

I plan on testing my “by now S.O.P” of purging the headspace against four other variants:

- Normal fill, with no headspace purge (control)

- No headspace purge, but very high bottle fill. This should leave very little to almost no headspace in the bottle after conditioning.

- Try to blow the gas under the beer surface to make it bubble and then cap on foam.

- The easiest and more reckless variant: fill without the wand, let the beer splash freely in the bottle. This should hopefully create some foam to cap upon.

This should make 8 bottles and 4 side-by-side comparisons. I would report back during January/February (should give them enough time to oxidise properly ;-)).
 
I’ll be bottling a batch on Friday and I am going to test the ideas that came up on this thread during the last days. I actually did not plan any specific “experiments” on this one, because it is not what I would consider a very hop forward beer by modern standards. It’s kind of a hybrid between a Belgian beer and an APA with “only” about 1.6 oz of dry hops (scaled to a 5 gal batch).

Still, since this thread has been revived (thank you guys), I’m eager to test new ideas, while preparing for my final boss (the NEIPA planned for next spring).

I plan on testing my “by now S.O.P” of purging the headspace against four other variants:

- Normal fill, with no headspace purge (control)

- No headspace purge, but very high bottle fill. This should leave very little to almost no headspace in the bottle after conditioning.

- Try to blow the gas under the beer surface to make it bubble and then cap on foam.

- The easiest and more reckless variant: fill without the wand, let the beer splash freely in the bottle. This should hopefully create some foam to cap upon.

This should make 8 bottles and 4 side-by-side comparisons. I would report back during January/February (should give them enough time to oxidise properly ;-)).
Awesome, thanks!!
 
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