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

[SwedishBrew]

I guess most important is not to shake the bottle atleast, I have been brewing for just a year and it kinds of boggles met that on all this instruction, people claim to shake the bottle to mix the sugar solution. This has literally ruined 5 - 6 batches. I do put the caps in a no-rinse solution just before cap it on the bottles, so it all works out fine

 

[Miraculix]

How can shaking ruin the batches? The O2 will get from the headspace air into the beer with time with or without shaking. The difference is, when shaking at the beginning, there might be a chance that the active yeast will still absorb it, as long as there is priming sugar in the solution.

Or does the anti oxygen cap take out the oxygen from the air in the headspace over time?

 

[Taket_al_Tauro]

While flipping or shaking after capping is completely unnecessary IMO (besides if you need to wet the O2-absorbing caps, as I learned here), I too do not think that this would be such a big driver of oxidation in bottle conditioned beers IF you can count on active yeast at bottling.

It could probably worsen the problem if the yeast ist not active (i.e. bottling cold beer after a cold crash).
In such a scenario you would further encourage O2 dissolution into beer while yeast is not yet able to metabolize it.

Ultimately O2 in the headspace will enter the beer no matter if you shake it or not.

 

[Brooothru]

So I don't bottle anymore except for competitions, so I really don't "have a dog in this fight". But for my edification on the question, for those rare occasions when I do bottle, does it help to 'wet' the O2 absorbing caps, as long as I don't shake the bottle? (serious Q)

 

[InspectorJon]

I'll add my experience to this discussion. This has yielded good results for me several times. I don't take any particular LODO precautions while brewing. I ferment in a glass carboy (I know...) and when fermentation is near done I seal it up with a mylar balloon so I can cold crash without suck back issues. I bottle directly from the fermenter to bottles that are individually primed using an auto siphon and bottling wand. I fill to very near the top and cap with oxygen absorbing caps. No purging or bubbling. I use my gravity testing graduated cylinder to pour enough beer into each bottle to get it right up near the top. This beer was bottled 60 days ago and is actually better now than it was a month ago. The bottle in the picture is one of the lower fills. I usually get a bit more in but at this point we are only talking about a few ml.

 

[Erik the Anglophile]

Been looking through the thread a bit because I have been thinking about starting to purge my bottles while bottling. What I make out is that I am good to go using my ordinary bottling method(transferring beer via tap on fermenter bucket to bottling bucket prepared with sugar solution, stir a bit gently and no splashing etc).
And then using one of those co2 pistols you can screw on soda stream type tubes and fill the headspace before putting on the cap and tighten it?

 

[Miraculix]

Been looking through the thread a bit because I have been thinking about starting to purge my bottles while bottling. What I make out is that I am good to go using my ordinary bottling method(transferring beer via tap on fermenter bucket to bottling bucket prepared with sugar solution, stir a bit gently and no splashing etc).
And then using one of those co2 pistols you can screw on soda stream type tubes and fill the headspace before putting on the cap and tighten it?

Create some foam with the co2 and cap on it

 

[Erik the Anglophile]

Create some foam with the co2 and cap on it

Foam? Like dipping the gun into the beer?

 

[Miraculix]

Beer + co2 = co2 foam

 

[Erik the Anglophile]

Beer + co2 = co2 foam

So basically insert the gun into the bottle and spray co2 until i see some foam on top of the beer? I'm still pretty noob at this...

 

[Miraculix]

So basically insert the gun into the bottle and spray co2 until i see some foam on top of the beer? I'm still pretty noob at this...

Oh, sorry, in my head you were using one of these co2 cans with the small pipe which can be dipped into the beer. I overread the beer gun. I don't know if this works with the gun as well.

 

[Erik the Anglophile]

Oh, sorry, in my head you were using one of these co2 cans with the small pipe which can be dipped into the beer. I overread the beer gun. I don't know if this works with the gun as well.

Haha, ok. My thought was to just use a soda stream can to purge the headspace, will still bottle condition.
Then i suppose just spraying until I see co2 smoke in the headspace and I'm good?

 

[Miraculix]

Haha, ok. My thought was to just use a soda stream can to purge the headspace, will still bottle condition.
Then i suppose just spraying until I see co2 smoke in the headspace and I'm good?

I guess it's the best you could do. Just be quick with the capping afterwards.

 

[Taket_al_Tauro]

So basically insert the gun into the bottle and spray co2 until i see some foam on top of the beer? I'm still pretty noob at this...

In my limited experience testing this idea/approach of blowing gas under the surface and then cap on foam, I found it difficult to make it work in practice, even when using a thin nozzle for the purging gas.

For one, if you cannot somehow regulate your gas flow, it is very easy to make a mess and have beer being blown out of your bottle.
Second, not every beer will foam up enough for it to work. Maybe it is dependant on the residual CO2 post fermentation or some other factors...

The easier way is to just purge the headspace. If possible, hold the cap with one hand on the bottle, and your purging device with the other. Just lift the cap a bit as to let your nozzle into the headspace. Give a quick burst of gas, then put on the cap immediately. If you have swing-tops you can actually seal immediately, otherwise I would just crimp them on as soon as practically possible.

Otherwise, even easier would be to just fill bottles near the top without doing any purging. A lot of people including one of the last posters here seem to have great success with this method. I definitely plan on testing this out more myself in the future...

 

[Miraculix]

I filled my last batch up to 3mm below the rim, let's see how that goes!

 

[Taket_al_Tauro]

Just for the record, this is the last bottle of the same NEIPA as in post #230, but this time I had a chance at a direct sunlight shot.
It is now 4 months post bottling almost to the day. Flavor-and aromawise it may not be what it was 2-3 months ago, but hell if it isn't hoppy still! I would happily drink this for another one or two months but sadly it is over.

 

[BrewnWKopperKat]

Just for the record

If you have time, can you post a detailed description of your bottling process here?

 

[Taket_al_Tauro]

If you have time, can you post a detailed description of your bottling process here?

My post fermentation and bottling process is a bit unorthodox compared to other IPA/NEIPA bottlers that will do some sort of cold crash to settle hops and then bottle directly from the fermenter into individually primed bottles...
You'll find all the relevant info on my process scattered through this thread, but it is true that I never wrote it down in one single post.

- Near the end of fermentation I raise temps to 72-74 F to let the yeast finish its job.
- Once fermentation is finished I keep the fermenters at this temperature for a few days.
- Then I let temps fall back to ambient temps of my basement (57 to 66 depending on season, for this particular NEIPA ist was around 66, since it was late summer).
- I wait another couple of weeks to let everything settle nicely (I do not cold crash), and then I dry hop. One single dry hop, so no dry hopping during fermentation. I added a tiny bit of sugar solution (approx. 1 oz of sugar for 7 gallons) and 1 gram/gallon of ascorbic acid together with the dry hops.
- Dry hop for 4-5 days.
- The evening before bottling I take the fermenters up in the house. The beer will continue to warm up to ambient temps during the night.
- I transfer the beer to a bottling bucket via siphoning from above. I place a deep monofilament filter bag in the bucket, and the beer will run through it. This gets rid of all but the finest dry hop particulate. Given that I do not cold crash and that I dry hop loose, I have lots of hop matter still floating aroung at the time of transferring.
- Then I bottle using a normal bottling wand. I still leave some headspace but I tried to reduce it a lot lately, by pressing the tip of the bottling wand against the neck at the end so as to release some more beer into the bottle.
- Then I purge the headspace as described in my original post, and seal the bottle immediately (swing top bottles).

Next on the list I want to experiment more with filling bottles up to near the very top.
And also, I want to confirm (or not) whether using ascorbic acid may make the purging step, or the no-headspace step, completely unnecessary. From the look of things the AA had a very noticeable effect, but more testing needs to be done.
Ultimately I want to move away from purging the headspaces and find a cheaper and more straightforward solution.

So this is my process, but I'm sure there are other ways of going about this that may be simpler, and yield the same or better results.

 

[Birrofilo]

@Miraculix

In answer to a post of yours earlier in this discussion, I bought today a cylinder with net 390g of liquid CO2, which will expand to 214 litres of CO2, for around €20 and I also needed a pression reducer which cost around €20 (can't find the exact prices now, but I am not wrong by much).

That kind of cylinder is not refillable. 214 litres is a lot of capping...

I also bought 3 metres of a silicon hose with an internal diameter of 3mm online for €9.

I will keep the cylinder outside away from sun rays. CO2 can be dangerous in high concentrations (or whatever it's the right word...) and I want to take into account the possibility of some defective valves.

 

[Miraculix]

@Miraculix

In answer to a post of yours earlier in this discussion, I bought today a cylinder with net 390g of liquid CO2, which will expand to 214 litres of CO2, for around €20 and I also needed a pression reducer which cost around €20 (can't find the exact prices now, but I am not wrong by much).

That kind of cylinder is not refillable. 214 litres is a lot of capping...

I also bought 3 metres of a silicon hose with an internal diameter of 3mm online for €9.

I will keep the cylinder outside away from sun rays. CO2 can be dangerous in high concentrations (or whatever it's the right word...) and I want to take into account the possibility of some defective valves.

Thank you very much for the information, much appreciated!

This is in a range of investment costs that I would be willing to take. Would you mind sharing direct links to the specific items you bought? If you don't want to share them here, pm would be fine as well. I just have no idea what I would need to look for, this would give me a good idea about where to start here in Germany.

Thanks!

 

[Taket_al_Tauro]

Thank you very much for the information, much appreciated!

This is in a range of investment costs that I would be willing to take. Would you mind sharing direct links to the specific items you bought? If you don't want to share them here, pm would be fine as well. I just have no idea what I would need to look for, do this would give me a good idea about where to start here in Germany.

Thanks!

Very interested as well... No idea where to find CO2 equipment that cheap. So far I only stumbled upon those mini keg chargers...quite cheap but also relatively tiny amounts of CO2 in those cartridges. And no precise idea on how to put together a practicable device for purging headspaces.
I already allowed myself to send him a PM about this, since I guess it only concerns us Europeans, but if he wants to share here, why not!

 

[Miraculix]

Very interested as well... No idea where to find CO2 equipment that cheap. So far I only stumbled upon those mini keg chargers...quite cheap but also relatively tiny amounts of CO2 in those cartridges. And no precise idea on how to put together a practicable device for purging headspaces.
I already allowed myself to send him a PM about this, since I guess it only concerns us Europeans, but if he wants to share here, why not!

I actually saw some regulators in the 20 euro range during a quick online search but I have no idea of they would fit the purpose. I have simply no clue about connection types, pressures, what type if container to connect to it and so on...

 

[Birrofilo]

Thank you very much for the information, much appreciated!

This is in a range of investment costs that I would be willing to take. Would you mind sharing direct links to the specific items you bought? If you don't want to share them here, pm would be fine as well. I just have no idea what I would need to look for, this would give me a good idea about where to start here in Germany.

Thanks!

I went to one of those hardware store chains, Leroy Merlin. Similar chains in Italy are Bricofer, Obi and others. There you have to look for the soldering sector. You will find there cylinders with oxygen, or CO2, and also argon and argon-CO2 mix.

There are let's say three kinds of cylinders that you can buy.

The large and serious cylinder, heavy to transport, which is used e.g. by people kegging the beer, or for real work in apartment restructuring etc. Those are refillable cylinders. They are filled at a very high pressure and have specific "valves" (pression reducers).
This is an example: Bombola Co2 da 4Kg Nuova ForHome® Ricaricabile Con Valvola Residuale Certificata
They might be overkill if the purpose is only capping.

Then you have the smaller, non-refillable cylinders. In the case of Oxygen, they come in two formats: small, around 24 litres of expanded gas, they are very light when you take them in your hand they seem empty, and "larger", not in physical dimensions but in weight and capacity, they hold more than 200 litres of expanded gas, the cylinder itself weights 1200g. Both kinds use the same pression reducers I do believe.
The pression reducer is often termed simply "for non-refillable cylinders", or it is termed "M10x1"

This is one example, a "heavier" CO2 non-refillable cylinder: Bombola a gas co2 AWELCO 0.95 L. Prezzo online | Leroy Merlin
The connector is called "filetto europeo", European thread, because that's a standard for those kind of cylinders. Basically M10x1, European thread or "for non-refillable cylinders" will get you the right pression reducer.

Note, though, that oxygen cylinders (which can be used for wort oxygenation, with a 0,5 micron aeration stone) need a specific pressure reducer, which is marked as "oxygen".

Actually now that I think about it, M10x1 is the one for oxygen, and generic "for non refillable cylinders" is for generic gas. Maybe (I did not test it) the two threads are different. [EDIT: tested, the thread is the same]

In any case, the assistant will give you the right pression reducer for the CO2 cylinder and the right pression reducer for the O2 cylinder. These cylinders typically are not sent by courier for the danger of explosion when left in hot temperatures, so you'll have to go to the hardware store.

Examples: Riduttore di pressione. Prezzo online | Leroy Merlin

The gas gets out through a "hose connector", you can couple there, typically, a hose with 3mm internal diameter. I bought this on Amazon.

Amazon.it

A silicon hose is very good because you can immerse it with the aeration stone in a vessel with water and sanitize, or even sterilize it with a microwave oven without having to touch the stone to fit the hose again, you just sanitize all together.

Oxygen is easily inflammable and CO2 can suffocate you and actually kill you, so this stuff is to be kept with some caution. I keep the cylinders outside but NOT in direct sunlight, that creates a danger of explosion.

In order to use them, you just close the tap on the reducer, fill the reducer on the cylinder, and then open the tap for the gas to get out. No particular manoeuvers.

The cylinder does not stand right by itself so I will use a bottle-holder to keep it up. One hand manovrates the gas tap, the other keeps the silicon hose inside the bottle. I will report here how it worked.

Just as we are there, this is an oxygen cylinder:

Bombola ossigeno per saldatura a gettare

Bombola ossigeno per saldara ossido acetilenica a gettare Codice originale marchio:UNIVERSALE (OXYGEN) Note descrittive:Cartuccia di Ossigeno per Turbo Set 90 Capacità 1lt - - Ennebiservice

ennebiservice.it

That's, again, more than 200 litres of oxygen. If you oxygenate beer (at pitching stage) with 1 minute at 1 litre/minute of flow, you have more than 200 batches of beer for this cost (plus the cost of the pressure reducer).

Oxygen for "soldering" is basically identical to the one used for medical purposes, for our goals. You will find very pure gases in there, no oils or other unwanted stuff.

Another option is to use the SodaStream cylinders with an adapter, as in this video:


"SodaStream" cylinders are actually generic gas cylinders of a standard which is called "S30", so you need an S30 CO2 cylinder, not necessarily a SodaStream.

 

[Miraculix]

I went to one of those hardware store chains, Leroy Merlin. Similar chains in Italy are Bricofer, Obi and others. There you have to look for the soldering sector. You will find there cylinders with oxygen, or CO2, and also argon and argon-CO2 mix.

There are let's say three kinds of cylinders that you can buy.

The large and serious cylinder, heavy to transport, which is used e.g. by people kegging the beer, or for real work in apartment restructuring etc. Those are refillable cylinders. They are filled at a very high pressure and have specific "valves" (pression reducers).
This is an example: Bombola Co2 da 4Kg Nuova ForHome® Ricaricabile Con Valvola Residuale Certificata
They might be overkill if the purpose is only capping.

Then you have the smaller, non-refillable cylinders. In the case of Oxygen, they come in two formats: small, around 24 litres of expanded gas, they are very light when you take them in your hand they seem empty, and "larger", not in physical dimensions but in weight and capacity, they hold more than 200 litres of expanded gas, the cylinder itself weights 1200g. Both kinds use the same pression reducers I do believe.
The pression reducer is often termed simply "for non-refillable cylinders", or it is termed "M10x1"

This is one example, a "heavier" CO2 non-refillable cylinder: Bombola a gas co2 AWELCO 0.95 L. Prezzo online | Leroy Merlin
The connector is called "filetto europeo", European thread, because that's a standard for those kind of cylinders. Basically M10x1, European thread or "for non-refillable cylinders" will get you the right pression reducer.

Note, though, that oxygen cylinders (which can be used for wort oxygenation, with a 0,5 micron aeration stone) need a specific pressure reducer, which is marked as "oxygen".

Actually now that I think about it, M10x1 is the one for oxygen, and generic "for non refillable cylinders" is for generic gas. Maybe (I did not test it) the two threads are different. [EDIT: tested, the thread is the same]

In any case, the assistant will give you the right pression reducer for the CO2 cylinder and the right pression reducer for the O2 cylinder. These cylinders typically are not sent by courier for the danger of explosion when left in hot temperatures, so you'll have to go to the hardware store.

Examples: Riduttore di pressione. Prezzo online | Leroy Merlin

The gas gets out through a "hose connector", you can couple there, typically, a hose with 3mm internal diameter. I bought this on Amazon.

Amazon.it

A silicon hose is very good because you can immerse it with the aeration stone in a vessel with water and sanitize, or even sterilize it with a microwave oven without having to touch the stone to fit the hose again, you just sanitize all together.

Oxygen is easily inflammable and CO2 can suffocate you and actually kill you, so this stuff is to be kept with some caution. I keep the cylinders outside but NOT in direct sunlight, that creates a danger of explosion.

In order to use them, you just close the tap on the reducer, fill the reducer on the cylinder, and then open the tap for the gas to get out. No particular manoeuvers.

The cylinder does not stand right by itself so I will use a bottle-holder to keep it up. One hand manovrates the gas tap, the other keeps the silicon hose inside the bottle. I will report here how it worked.

Just as we are there, this is an oxygen cylinder:

Bombola ossigeno per saldatura a gettare

Bombola ossigeno per saldara ossido acetilenica a gettare Codice originale marchio:UNIVERSALE (OXYGEN) Note descrittive:Cartuccia di Ossigeno per Turbo Set 90 Capacità 1lt - - Ennebiservice

ennebiservice.it

That's, again, more than 200 litres of oxygen. If you oxygenate beer (at pitching stage) with 1 minute at 1 litre/minute of flow, you have more than 200 batches of beer for this cost (plus the cost of the pressure reducer).

Oxygen for "soldering" is basically identical to the one used for medical purposes, for our goals. You will find very pure gases in there, no oils or other unwanted stuff.

Another option is to use the SodaStream cylinders with an adapter, as in this video:


"SodaStream" cylinders are actually generic gas cylinders of a standard which is called "S30", so you need an S30 CO2 cylinder, not necessarily a SodaStream.

Wow, thank you, great information!!!

 

[Taket_al_Tauro]

Another option is to use the SodaStream cylinders with an adapter, as in this video:

Thanks for the infos. Without having the time to delve into it much deeper for the moment, I really like the Soda Stream cylinder idea. I'll have to find out how or where to get one of those adapters here.
It seems to me that you could easily rig it up as to handle the cylinder and valve with one hand, and the bottles/caps with the other.

 

[Taket_al_Tauro]

So I have a question for the experts on gas physics here (maybe a stupid one, or one that has already been answered X-times in this forum before…apologies if that’s the case).

If we assume, like it is often stated here and elsewhere, that bottle caps do not seal 100% airtight, and that some albeit very reduced rate of gas exchange will still be happening… then why is there no significant carbonation loss in beer over a long aging period?

The partial CO2 pressure inside a bottle of beer is of an order of magnitudes higher than the partial CO2 pressure in the air. As a consequence, shouldn’t the CO2 be able to gradually escape the bottle?


Is it because those seals are only permeable to O2, but not to CO2?


Same for PET: Is this material permeable to O2, but on the other hand very effective at blocking CO2? Otherwise I’d guess that one should notice some carbonation loss over time in soda drinks stored in PET?

 

[Vale71]

If we assume, like it is often stated here and elsewhere, that bottle caps do not seal 100% airtight, and that some albeit very reduced rate of gas exchange will still be happening… then why is there no significant carbonation loss in beer over a long aging period?

That's because there is an actual loss of carbonation but it will take a really long time (like several years) for it to become noticeable. That is, if it becomes noticeable at all. If there is any further fermentation, either because of an infection or because the beer is not pasteurized and there is some residual fermentable extract, this might more than compensate for the loss of carbonation.
Same goes for PET bottles, there is some loss but since nobody will store soda drinks for, say, 5+ years, which would be well past any "best before" date, this doesn't get noticed in practice.

 

[Taket_al_Tauro]

That's because there is an actual loss of carbonation but it will take a really long time (like several years) for it to become noticeable. That is, if it becomes noticeable at all. If there is any further fermentation, either because of an infection or because the beer is not pasteurized and there is some residual fermentable extract, this might more than compensate for the loss of carbonation.
Same goes for PET bottles, there is some loss but since nobody will store soda drinks for, say, 5+ years, which would be long past any "best before" date, this doesn't get noticed in practice.

Thanks, makes sense.
I might try to keep one mineral water or soda bottle in my cellar and come back here in 10-20 years to report my observations

 

[doug293cz]

This thread has devolved into an argument with too much name calling. It is now closed.

 

[doug293cz]

Problematic posts have been deleted, and the thread reopened. DO NOT restart any of the old disagreements that got this thread closed. This thread will be heavily moderated going forward.

doug293cz

 

[BrewnWKopperKat]

First, thank you @doug293cz for unlocking this topic.

Next, for those who have been reading / experimenting with "advanced" bottling techniques that minimize 'oxygen ingress' damage, what is "new" recently?

Finally (for the moment anyway), this is my reading / research list from early Feb 2021. Is there new content that could be added? Information that suggests some techniques are not reproducible?

@Taket_al_Tauro - here are links to what I found in my notes.

HomeBrewTalk
How to bottle NEIPA (without kegging)
Limiting oxidation: effect of purging headspace O2 in a bottle conditioned IPA
Limiting oxidation: effect of purging headspace O2 in a bottle conditioned IPA
NEIPA Bottle Oxidation and alternatives?
Purging headspace when bottling
A thought experiment for reducing oxygen naturally when bottling

AHA Forums
Topic drifted into bottling - the links in reply 29 may be of interest

/r/homebrewing
Actually, you can bottle NEIPAs at home ...
Tips to bottle a hazy/new England IPA with minimizing oxidation?
Tired of carbonation issues when bottling? Try dosing your bottles with ...
I did it. I bottled my first brew!
Individual bottle priming using sugar solution: ...
Very happy with how my Bottle Filler turned out

eta: list created based on bookmarks on or before 2/4/2021 0:00 UTC

eta (2/8 4:30 et)
Bottling tips

 

[CascadesBrewer]

Problematic posts have been deleted, and the thread reopened. DO NOT restart any of the old disagreements that got this thread closed. This thread will be heavily moderated going forward.

Awesome! This thread is a wealth of knowledge. I am starting to think that oxidation of bottled beers is one of those big issues that has gotten overlooked for years. I just accepted the "the yeast will consume all the oxygen" line, which I now believe to be a myth.

Oxidation with bottle conditioned NEIPAs is a clear issue because it is so visible and has a drastic impact on the flavor. I wonder how much of an issue bottle oxidation is with other styles. With something like a Porter or an Irish Red, is it even worth thinking about? What about a Barleywine that you plan to age for years? What about a Pilsner where you rely on the subtle grain character and hop flavors?

I did an experiment similar to some of the ones discussed earlier. I wrote about it here: Avoid Bottling Oxidation for Hoppy Beers | Cascades Homebrew

There is more info in my article, but I will throw a pic and some info here. note: I had a hell of a time getting quality pictures that represented what I was seeing in person.

• Squeezed: This bottled was squeezed just before capping to remove the air from the headspace.
• Campden: This bottle got a small amount of a crushed campden tablet at bottling. The amount was small enough that I did not have a means to measure how much was added. I am willing to discount this one as a possible failure of my process.
• None: This one was just filled following what was my standard bottling process. The beer was filled to the rim, and the headspace is the amount left after removing the bottling wand.
• Purged: This is the same process used for the prior Pale Ale and the other bottles. I simply ran a gentle stream of CO2 into the headspace before capping.

 

[Taket_al_Tauro]

Since @doug293cz was so kind to clean up and reopen this thread (thank you!), I'll also post a few observations from my latest little "experiment".
The goal with this beer was a NE-style pale. It turned out less hazy than expected I guess due to a lower dry hopping load than in a regular NEIPA and also the specific yeast blend I used this time.

I added some ascorbic acid to this one as well, and this is actually the main point of this post.
Because I again compared some different headspace-handling variants, and there were no perceivable differences, neither in color nor in aroma/taste.
So it really seems that the AA is doing its job for me.
Based on previous experiences, I am nearly 100% sure that without the AA I would be getting some differences between those variants, at those hop loads.

Again, pretty poor lighting on the pic but believe me, they are a nice blond color in reality
This is approx. 3 months after bottling. I should have tested them earlier, but did not find another suitable slot for drinking 3 beers in one run... the problems I have.

The tested variants were:
Left: Non purged, and standard headspace as I used to do originally (meaning the headspace resulting after removing a standard bottling wand)
Middle: Non purged, reduced headspace (the headspace I'm usually leaving now, after removing the wand and filling some more beer, approx. 0.7 to 1.0 inch)
Right: Purged with Private Preserve plus reduced headspace.

 

[CascadesBrewer]

I added some ascorbic acid to this one as well, and this is actually the main point of this post.

What is your current process for adding the ascorbic acid?

I have also been curious how much impact oxygen absorbing bottle caps have. In my experiment above, the only clear bottles I had were PET ones with screw on caps. The other beers were bottle into recappable swing tops. In all cases I did not have any benefit from oxygen absorbing caps. It could be that those caps do a decent job of reducing oxygen in a bottle headspace.

 

[Taket_al_Tauro]

What is your current process for adding the ascorbic acid?

I add the AA in the fermenter together with the dry hops, that is 3-5 days prior to bottling.
I first dissolve the AA in a little bit of boiled water.
I've been going for the dosage originally suggested by @tyrub42 in this thread.
That is about 1 gram per gallon. On this last one I think I did a bit less, maybe 0.8 - 0.9 g/gallon.
It seems this dosage is quite high, and some people in this thread were raising concerns that it is way above the legal limit for commercial beverages.
OTOH, the concentration of natural AA in e.g. orange juice is even higher than that (and by a significant margin, if I am not mistaken)... but then again,
people do not usually drink one or two pints of orange juice the same day, right?

Anyway, going forward I'll try to reduce it and at the same time observe if there are no negative impacts (those might range from simply losing its beneficial effect up to the purported "super oxidizer effect" that may come from an AA-dosage that is not high enough).
My goal would be to come into the range of 15 g/hl or even below, which translates to roughly 0.55 g/gallon. That seems to be the current legal limit for AA as an adjunct in commercial beverages in the EU, as mentioned by @Birrofilo also in this thread.
And of course, I am adding it only to hop-forward beers that are also dry hopped.

have also been curious how much impact oxygen absorbing bottle caps have. In my experiment above, the only clear bottles I had were PET ones with screw on caps. The other beers were bottle into recappable swing tops. In all cases I did not have any benefit from oxygen absorbing caps. It could be that those caps do a decent job of reducing oxygen in a bottle headspace.

I have personally no experience with those caps (I am using swing tops exclusively). Howewer, there was a member in another thread that did a similar little experiment with those, and if I recall correctly he did not find a perceivable beneficial effect from using those against standard caps.

 

[Brooothru]

O.K. I want to tread lightly and not resurrect old demons..... but what about Trifecta as opposed to just ascorbic acid for O2 mitigation? I've been having very good luck adding Trifecta to the mash and an additional dosing about :05 minutes before the end of boil.

I don't brew NEIPAs, but my hoppy WC IPAs and even Continental lagers seem to stay fresher longer, with hops that don't fade as quickly.

I currently have a very hoppy (6 varietal, 95 IBU) beer that's conditioning. So far it seems to be holding its own in freshness and hop aroma. The true test will be after a month or more in the keg. I plan to bottle about a dozen to see if they withstand the test of time. I'll report back this fall.

 

[BrewnWKopperKat]

what about Trifecta

If you write up your process and post it [maybe here, maybe elsewhere with a link here], people may give it a try.

I currently have ... . I plan to bottle about a dozen to see if they withstand the test of time. I'll report back this fall.

Looking forward to the results!

 

[Brooothru]

If you write up your process and post it [maybe here, maybe elsewhere with a link here], people may give it a try.


Looking forward to the results!

Presently on the road without access to my notes or brewlogs, but basically I treat the strike water (approx. 34 liters) with 1.8 grams of Trifecta blend of BrewTan B, NaMeta and ascorbic acid) followed up with 1.4 grams just before flame out in the boil. I'll dig up the exact amounts of each to achieve the desired parts per million in the wort when I get back home.

Basically, less can be more, but the documented results the German brewers were getting of residual dissolved O2 were eye-watering. I'll add that the clarity of wort going into the fermenter after whirlpooling and setting is nothing short of amazing.

 

[BrewnWKopperKat]

Presently on the road without access to my notes or brewlogs, but basically I treat the strike water (approx. 34 liters) with 1.8 grams of Trifecta blend of BrewTan B, NaMeta and ascorbic acid) followed up with 1.4 grams just before flame out in the boil. I'll dig up the exact amounts of each to achieve the desired parts per million in the wort when I get back home.

Basically, less can be more, but the documented results the German brewers were getting of residual dissolved O2 were eye-watering. I'll add that the clarity of wort going into the fermenter after whirlpooling and setting is nothing short of amazing.

Thanks. I'll suggest setting up a separate topic and linking to it here for people to consider. That way each topic will have the opportunity to stay focused on their primary topic.

 

[Taket_al_Tauro]

followed up with 1.4 grams just before flame out in the boil.

What is the purpose of adding the antioxidant blend at the end of the boil?
Is it to prevent oxidation of wort during the whirlpooling and chilling phase?

Because once the wort is chilled, I assume you are going to aerate or oxygenate it, so basically flooding it with O2 and pitch the yeast.
At least part of that O2 will react with the residual antioxidant, I guess. So won't this step work against both the purposes of having antioxidants in the wort and maximizing O2 in the wort (post chilling) for yeast growth?
Sorry I'm not trying to be argumentative or anything, just want to understand. I'm sure there is a link in the chain I am still missing here.
(with those old demons you mentioned one has to be careful )