Purging headspace when bottling

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I have been reading these threads with interest as I have just bottled my first NEIPA. Prior to deciding to brew a NEIPA I wasn't aware they where so sensitive to oxidation so hadn't intended on doing anything different to how a usually bottle. Which just involves a filling stick and bottle caps, no purging, shaking or anything else. I don't have any access to CO2 or kegs so most of the suggestions above are not an option for me.

But since I was reading all these threads while fermenting I figured I needed to do something quick so I opted to get some oxygen scavenging caps and reduce the headspace remaining in the bottles when filling. So that is what I did. But my reason for posting is that I have filled 3 clear bottles so I can monitor what happens over time without opening them. I have seen that a few people have done similar tests before but I don't think its been done with oxygen scavenging caps.

I have filled one bottle as I usually would and capped with a normal cap, one bottle filled as normal and capped with oxygen scavenging cap, and one bottle filled to a few mm from the top and then capped with oxygen scavenging cap. I have photographed the bottles and will check them from time to time to see if I get any differences.

I have started another thread at the following link

Oxygen Scavenging bottle cap test

For the record, regarding the co2 purging discussion, I think that if there is a way to achieve co2 bubbles successfully in each bottle, and the bubbles fill all the way to the top of the bottle then this in my unscientific opinion has to be the most likely to reduce oxygen levels. But if fancy caps can achieve the same thing its got to be easier......
 
If you plan to consume all of your beer within about 3 to perhaps 4 months max, then bottling it in an oxygen barrier equipped amber PET bottle which has been squeezed whereby to fill the bottle to a bit over completely full before simultaneously screwing on the cap will remove all headspace oxygen.
 
I have started another thread at the following link
I saw the post & "bookmarked"/"followed" it. I'm looking forward to reading what you find.

I see that some discussion has already started in that topic. You may want/need to start a new topic with before / after posts when you have new information.
 
If you plan to consume all of your beer within about 3 to perhaps 4 months max, then bottling it in an oxygen barrier equipped amber PET bottle which has been squeezed whereby to fill the bottle to a bit over completely full before simultaneously screwing on the cap will remove all headspace oxygen.
Do you have a recommended source for those bottles?
 
Do you have a recommended source for those bottles?

Coopers, or Mr. Beer if you are in the USA. When Coopers amber oxygen barrier PET beer bottles seemed to suddenly vanish in the USA, I emailed Coopers to ask them when/if they would be returning to this market, and they directed me to Mr. Beer. Try amazon.com perhaps.

Mind you, I haven't tried this personally (yet) but there is a YouTube video where a guy did this and got just about as good a result for his IPA as for purged keg beer. The PET bottled IPA stayed yellow while the glass bottled beer turned a yucky brown. I've heard that all such bottles are somewhat flimsy, but the 740 mL version is 'reportedly' a bit more robust than the 500 mL version.
 
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There will always be oxygen ingress with PET bottles, even if they have an oxygen barrier. That said, if glass bottled turns brown in about 2 weeks (as has happened to me with IPA's), and it takes 3-4 months to arrive at the same fate with PET, then.... Even 2 months vs. 2 weeks would be an improvement.
 
The drawbacks for me (that have been holding me back) are the outrageous cost and 500 mL or 740 mL vs. 330 mL or ~355 mL (12 Oz.).
 
That said, if glass bottled turns brown in about 2 weeks ...

In a couple of other topics (which I mentioned earlier, but including them again for clarity),
people are currently getting good results 40+ days after packaging.

PET bottles are certainly an option that could be considered - which is why I was asking for current sources for buying the bottles.
 
I sort of like the Ascorbic Acid idea. There is much peer reviewed literature that says it can turn on you and become a super-oxidizer, but I did come across one peer reviewed document which stated that this nasty turn can be avoided if some critical mass of Ascorbic Acid is added per unit volume. The 2nd link in the above post said an estimated 3-4 grams were added to what I believe was 5 gallons. That amount may get you above the threshold for turning Ascorbic Acid into a super-oxidizer. ??? Flavor impact might be another concern. ???
 
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I sort of like the Ascorbic Acid idea. There is much peer reviewed literature that says it can turn on you and become a super-oxidizer, but I did come across one peer reviewed document which stated that this nasty turn can be avoided if some critical mass of Ascorbic Acid is added. The 2nd link in the above post said an estimated 3-4 grams were added to what I believe was 5 gallons. That amount may get you above the threshold for turning Ascorbic Acid into a super-oxidizer. ??? And flavor impact might be another concern.

FWIW I used about 1 gram/gallon as per @tyrub42 's original suggestion in one of the above mentioned threads.
It seemed to work really well for me.
No flavor impact whatsoever that I could detect.
Also no noticeable effect on beer pH
(it's probably too weak of an acid to have a significant effect on pH at that dosage).
 
I sort of like the Ascorbic Acid idea.
My IPA’s use 1 teaspoon per keg ascorbic acid. I’m a believer, here is my Barney the Welder clone next to the original Pliny the Elder.
AAA98EEF-E9C4-480C-B84F-9B9411B0A3E1.jpeg
 
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My IPA’s use 1 teaspoon per keg ascorbic acid at bottling time. I’m a believer, here is my Barney the Welder clone next to the original Pliny the Elder.

Nice! Did you also purge the headspace of the bottles with CO2, or was all of the benefit derived from solely the Ascorbic Acid?

I believe that 1 measuring TSP of finely powdered AA should be about 5.3 grams. A common tableware TSP would likely be somewhat less. Perhaps 4 to 4.5 grams. I'd say that about 1 gram per gallon seems about right for avoiding the super oxidizer issue and providing a high degree of antioxidant benefit. Less may also work, but at some lower quantity it will potentially turn and do the opposite of being beneficial.

Can you taste it?
 
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Correction on the above, it goes into the keg prior to bottling time at the same time you do your gelatin fining. Ascorbic acid gets mixed with cool boiled water not hot. Not sure on the metric conversion. Then I purge the keg 15 cycles. I used bottle conditioning tablets on IPA’s and shoot a little CO2 under the cap. I have a little picnic tap hooked up to CO2 for this. Lots of little tricks to minimize O2!!
 
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I'd say that about 1 gram per gallon seems about right for avoiding the super oxidizer issue and providing a high degree of antioxidant benefit. Less may also work, but at some lower quantity it will potentially turn and do the opposite of being beneficial.

Is "gallon" 3,78 litres or 4,55 litres in this context? I suppose it's 3,78. That's a lot of ascorbic acid in your brew.

It's the risk of the super-oxidizer issue increasing with a decreasing amount of ascorbic acid?
Or is the other way round?

Do you have any link to some study or empirical evidence? I did not find any clear and understandable source talking about when and how this thing happens, and how to contrast it. It's not clear to me in which circumstances will the ascorbic acid "kick back". It appears sulphite are some sort of insurance against this, but it's a stinking insurance.

I am a believer myself, I bought ascorbic acid, I plan to find a place for it in my procedure (which is not easy as I normally inject the priming sugar directly in the bottle, unless I have to make a dry-hopping). I might mix ascorbic acid to the beer a few days before bottling, mixing it all up and waiting again for the dust to settle.
I am quite struggling in the decision about how much to use it, and how to avoid the kick-back effect.

I have two options to choose from:

a) ascorbic acid bomb: 1 g per US gallon. That appears to simply work. But it's a lot. According to some sources the maximum limit in Italy (and in the EU presumably) is 15g/hl, if "gallon" is a US gallon, 1g/gallon means 26,42 g/hl, way above the maximum limit established by the law here. I know this is, in theory, vitamin C, and its harmfulness should manifest only at much higher doses, but I don't think passing the law limit is wise, and theory and reality might differ.

b) little ascorbic acid, 4g/hl (1g for a normal 20 litres batch) supplemented by very little sulphide, something like 5 ppm or 5 mg/l. Sulphites are something hideous, and the opposite of what home-made natural product should aim to, but we are talking here a quantity which is naturally contained in wines and ciders, and half the threshold for the "contains sulphite" label mention for any food. That means that beer in commerce might have 5ppm sulphite and no mention in the label (unless the label says Gebraut nach dem Reinheitsgebot, that is).
 
which is not easy as I normally inject the priming sugar directly in the bottle, unless I have to make a dry-hopping
People who talk about bottling occasionally mention making a sugar solution, then using a medicine dropper to dose individual bottles. Could that technique be extended to include ascorbic acid?
 
People who talk about bottling occasionally mention making a sugar solution, then using a medicine dropper to dose individual bottles. Could that technique be extended to include ascorbic acid?

In fact, Jesus, now that you say that, what's the problem with mixing the ascorbic acid into the priming syrup? If one mixes it well, it should work.

I had ruled out the in-bottle injecting for the dry-hopping alcoholic tincture because volume calculations become difficult and part of the hop would be wasted (just like part of the sugar is wasted).

But one can easily calculate an exact dosage "per liter" of ascorbic acid, add it into the syrup, and inject the syrup inside the bottles with the correct amount of ascorbic acid. There is no noticeable volume increment and no new calculation to make. No problem also for the little quantity of ascorbic acid that is wasted.

That means that I will insert the ascorbic acid thing in the bottling procedure in any case. I just have to understand better the kick-back effect and whether to use ascorbic acid alone or in conjunction with a very little quantity of sulphites.

Thanks!
 
Is "gallon" 3,78 litres or 4,55 litres in this context? I suppose it's 3,78. That's a lot of ascorbic acid in your brew.

It's the risk of the super-oxidizer issue increasing with a decreasing amount of ascorbic acid?
Or is the other way round?

Do you have any link to some study or empirical evidence? I did not find any clear and understandable source talking about when and how this thing happens, and how to contrast it. It's not clear to me in which circumstances will the ascorbic acid "kick back". It appears sulphite are some sort of insurance against this, but it's a stinking insurance.

I'm merely going off of the testimony of a couple people on this forum who have added exclusively 1 TSP of powdered Ascorbic Acid to 5 US gallons and reported stellar antioxidant results with no reported negative flavor impact. All that I have uniquely attempted to do is to quantify 1 TSP of powdered Ascorbic Acid in terms of grams.
 
People who talk about bottling occasionally mention making a sugar solution, then using a medicine dropper to dose individual bottles. Could that technique be extended to include ascorbic acid?

I make sugar solutions in water and syringe inject them into my beer bottles to prime (before filling them). I (initially at least) think that adding the Ascorbic Acid to this mixture should work fine.
 
I'm merely going off of the testimony of a couple people on this forum who have added exclusively 1 TSP of powdered Ascorbic Acid to 5 US gallons and reported stellar antioxidant results with no reported negative flavor impact.

Being one of these couple people, I would relativize the "stellar" for my part and for the time being. It seemed to work well, yes, but I was also implementing other measures to limit the impact of O2 at the same time.
What speaks for the ascorbic acid, besides the NEIPA turning out really good IMHO, is that there was no difference between a headspace-purged and a non headspace purged control variant (whereas there were always differences, at least visual, between such variants in all my previous hop forward beers without ascorbic acid).

I'm just talking from my very limited experience using it so far (I do not brew that many IPAs/NEIPAs and unfortunately do not brew that often in general at the moment). I will use it again for sure and plan on doing some more comparisons to figure out whether its effect is really consistently stellar :)

There is much peer reviewed literature that says it can turn on you and become a super-oxidizer, but I did come across one peer reviewed document which stated that this nasty turn can be avoided if some critical mass of Ascorbic Acid is added per unit volume.

If you have a link to that study you mention, I'd be interested. Thanks!
 
If you have a link to that study you mention, I'd be interested. Thanks!

A quick search of peer reviewed research documents revealed this quoted reference wherein it is mentioned that:
indeed it was found that if insufficient ascorbic acid were added to beer, the dehydroascorbic molecule could actually act as an oxygen carrier and catalyze oxidation of beer, making things worse instead of better.
I read this as an indication that if "sufficient" ascorbic acid is added this highly undesirable consequence will be avoided. Unfortunately no quantification of this sufficiency level is discussed.

Here is the link: https://www.onlinelibrary.wiley.com/doi/epdf/10.1002/j.2050-0416.1973.tb03517.x

See page 153 near the bottom left under "Antioxidants".
 
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A quick search of peer reviewed research documents revealed this quoted reference wherein it is mentioned that:

I read this as an indication that if "sufficient" ascorbic acid is added this highly undesirable consequence will be avoided. Unfortunately no quantification of this sufficiency level is discussed.

Here is the link: https://www.onlinelibrary.wiley.com/doi/epdf/10.1002/j.2050-0416.1973.tb03517.x

See page 153 near the bottom left under "Antioxidants".

Thanks!
Yes, unfortunately no mention of a "sufficient quantity". I'd like to reduce too, because 1 gram/gal does seem a lot to me as well. However, for this one time a year I'm brewing a NEIPA with lots of $$ in hops I want to maximize its chances of success, so I'll probably continue with that dosage for now....unless people start reporting consistent good results with smaller additions.

BTW I really liked the final part of that paper where they were talking about yeast - the best of all antioxidants!
 
Yes, I also was surprised by the conclusion. Basically a "vigorous secondary fermentation" is described as the best antioxidizing method.

Time to get that Fermentis F-2 out of the freezer maybe...
 
Thanks!
Yes, unfortunately no mention of a "sufficient quantity". I'd like to reduce too, because 1 gram/gal does seem a lot to me as well. However, for this one time a year I'm brewing a NEIPA with lots of $$ in hops I want to maximize its chances of success, so I'll probably continue with that dosage for now....unless people start reporting consistent good results with smaller additions.

BTW I really liked the final part of that paper where they were talking about yeast - the best of all antioxidants!
I read in a German wine and mead forum about someone who was doing a quick and dirty port wine-ish thing by adding ascorbic acid and then shaking the hell out of it. After a minute it was fully oxidised and changed completely the taste. This did not happen without the ascorbic acid.
 
I read in a German wine and mead forum about someone who was doing a quick and dirty port wine-ish thing by adding ascorbic acid and then shaking the hell out of it. After a minute it was fully oxidised and changed completely the taste. This did not happen without the ascorbic acid.

Without wanting to do it un purpose, that was the experience of many persons who, in the 1960s, with the recent "motorization" of the Italians, would take their new car and go buy wine in the wine district south of Rome, in the Colli Albani "district". In the cellar you taste the wine just spilled from the vat, and it's deliciously perfumed ("hawthorn" and "almond" are often cited in literature, I have no idea how hawthorn smells, when I see one I will recognize it because it smells like Frascati) so you buy 50 litres, which they will put into plastic tanks meticulously cleaned. Problem is, you have to drive from there to your Roman house and in the process the wine will mix with air greatly.

When you taste the wine at home, it's a disappointment. It was so good in Grottaferrata!

Always buy wine in bottles! Much less damage!

Sorry for the slight :off:
 
I also recall seeing mention in a peer reviewed document that when ascorbic acid is added at a level below 100 mg/Kg it acts as a super oxidant. But I can't presently locate this reference.

Extending this to 5 gallons, and presuming 5.5 gallons in the fermenter, and an FG of 1.010:

5.5 x 3.7854 x 1.010 = 21.03 Kg.
100 mg/Kg x 21.03 Kg = 2,103 mg = ~2.1 grams of Ascorbic Acid as the very minimum addition level, below which disaster awaits

So if 5 grams works for 5 gallons, and 2.1 grams is bordering upon sure failure, then splitting the difference between them derives:
(2.1 + 5)/2 = 3.55 grams

Attempt this at your own risk!
 
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I found today this interesting video with a visual demonstation of how CO2 forms pockets which don't dissolve into outside air, in the open.



Seeing the engagement there is, in this forum, to "burst" the "myth" of CO2 making layers, I think this is "food for thought", as they say.
 
I found today this interesting video with a visual demonstation of how CO2 forms pockets which don't dissolve into outside air, in the open.



Seeing the engagement there is, in this forum, to "burst" the "myth" of CO2 making layers, I think this is "food for thought", as they say.

This adds nothing to the discussion. For a mazuku to exist for more than a few tens of minutes, there has to be source supplying CO2 faster than diffusion dissipates the CO2. This has been discussed at length above.

Brew on :mug:
 
Normally there is a bit of CO2 in the beer being bottled. Don't immediately cap the bottle. Set the sanitized cap on top of the bottle while filling the other bottles. Will hear the "dancing caps" phenomenon. I'm still waiting for the Sci-Fi channel to show up and record this "paranormal" event.
 
This adds nothing to the discussion. For a mazuku to exist for more than a few tens of minutes, there has to be source supplying CO2 faster than diffusion dissipates the CO2. This has been discussed at length above.

Brew on :mug:

That is why I added this to the discussion.
The objection is that if there is a continuing source of heavy gas, the heavy gas will stratify initially, because of its continuing supply, but after the supply ends, the diffusion will prevail and the stratification will end.

This video appears to show the opposite.

The CO2 comes from nearby lakes where some geological phenomenon shakes the CO2 and liberates it from the water. This is called from what I learn "limnic eruption"

https://en.wikipedia.org/wiki/Limnic_eruption
The CO2 doesn't originate where you see the CO2 polls forming, but elsewhere in the region on a lake.

The CO2 will accumulate in those low sacks of terrain but it is not formed there. If this is the case, that negates the theory that diffusion always prevails. The air of the "region" has an anomalous content of CO2, which is slowly collected into those depressions where it creates dangerous sacks. The polls are open to air, yet the CO2 remains concentrated in the polls.

The phenomenon is called in local language "evil wind"

https://en.wikipedia.org/wiki/Mazuku
The CO2 is not coming from the ground, but can accumulate coming from elsewhere.

Even if, as you might maybe think, the creation of CO2 from the limnic eruption were continuous (which I understand is not), the fact that the pockets are created far from the lakes show that the stratification happens regardless of the laws of diffusion of ideal gases. The lakes "burp" the CO2 and that accumulates at kilometres from there, in depressed spots.

The name itself, "evel winds", shows that the phenomenon is not continuous or stable, as it would be if the CO2 creation came from under the ground. In that case, the precise spot would be considered simply unsafe. But what is unsafe is the "wind", which carries the CO2 from elsewhere.
 
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That is why I added this to the discussion.
The objection is that if there is a continuing source of heavy gas, the heavy gas will stratify initially, because of its continuing supply, but after the supply ends, the diffusion will prevail and the stratification will end.

This video appears to show the opposite.

The CO2 comes from nearby lakes where some geological phenomenon shakes the CO2 and liberates it from the water. This is called from what I learn "limnic eruption"

https://en.wikipedia.org/wiki/Limnic_eruption
The CO2 doesn't originate where you see the CO2 polls forming, but elsewhere in the region on a lake.

The CO2 will accumulate in those low sacks of terrain but it is not formed there. If this is the case, that negates the theory that diffusion always prevails. The air of the "region" has an anomalous content of CO2, which is slowly collected into those depressions where it creates dangerous sacks. The polls are open to air, yet the CO2 remains concentrated in the polls.

The phenomenon is called in local language "evil wind"

https://en.wikipedia.org/wiki/Mazuku
The CO2 is not coming from the ground, but can accumulate coming from elsewhere.

Even if, as you might maybe think, the creation of CO2 from the limnic eruption were continuous (which I understand is not), the fact that the pockets are created far from the lakes show that the stratification happens regardless of the laws of diffusion of ideal gases. The lakes "burp" the CO2 and that accumulates at kilometres from there, in depressed spots.

The name itself, "evel winds", shows that the phenomenon is not continuous or stable, as it would be if the CO2 creation came from under the ground. In that case, the precise spot would be considered simply unsafe. But what is unsafe is the "wind", which carries the CO2 from elsewhere.
The video says nothing about the source of the CO2 for that particular muzuku.

CO2 can come out of fissures in the earth, from other volcanic activity, and lakes with high dissolved CO2. The amount of CO2 coming from any of these sources can overwhelm diffusion, until the source stops producing CO2.

Brew on :mug:
 
The photo below is from a batch that was bottled 4 months ago. I held on to this last bottle for a while to see how it would age just for kicks. Aside from the turbid haze settling out, the color is great as was the hop character. This basically looked like old fashioned chill haze. It looked much more like a classic NEIPA in the first couple months. No oxidation to speak of though after 4 months.

My process was to bottle straight from the primary via the spigot with a bottling wand attached. Priming sugar was dosed into each bottle and then infilled to the top and capped immediately. No purging at at any stage.
746709E2-82DE-49BE-8AEF-441FE4EB6F2B.jpeg
 
I read in a German wine and mead forum about someone who was doing a quick and dirty port wine-ish thing by adding ascorbic acid and then shaking the hell out of it. After a minute it was fully oxidised and changed completely the taste. This did not happen without the ascorbic acid.

I am re-reading this and I realized I read it the opposite way the first time.
Do you really mean that shaking the wine produced oxidation with the ascorbic acid and did not produce oxidation without it? You probably meant the opposite.
 
I am re-reading this and I realized I read it the opposite way the first time.
Do you really mean that shaking the wine produced oxidation with the ascorbic acid and did not produce oxidation without it? You probably meant the opposite.
Nope, I meant it the way I wrote it. I think an excessive dosage might be the reason.
 

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