oxigen exposure: racking to secondary Vs racking to bottling bucket

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javierceras

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Hi there,
Nowadays, (almost) everybody agrees on skipping secondary due to a number of reasons, the risk of oxigen exposure being one of the most cited...
But then, what is the difference in racking to a secondary (and bottling directly from the secondary to bottles, that is, just one transfer) Vs racking to a bottling bucket (just one transfer)?
I don't see much difference after all... but I'm just a newbie
Thanks for your help!!
 
Hi there,
Nowadays, (almost) everybody agrees on skipping secondary due to a number of reasons, the risk of oxigen exposure being one of the most cited...
But then, what is the difference in racking to a secondary (and bottling directly from the secondary to bottles, that is, just one transfer) Vs racking to a bottling bucket (just one transfer)?
I don't see much difference after all... but I'm just a newbie
Thanks for your help!!
The difference is that the yeast is active again in the bottle and quickly scavenges the oxygen in solution. The yeast in secondary is dormant so the oxygen has the time to go rampage on your beer.

The problem with bottling is not the oxygen in solution, but the oxygen in the headspace of the bottle. The oxygen from there gets slowly into solution, also after the carbonation sugar is finished and then it does damage. Therefore, limit the headspace to the physical minimum without risking bottle bombs, i.e. 0.5-1cm headspace.
 
Not only is the yeast woke up and embarking on another fermentation process by the priming sugar or wort, the bottle caps themselves that many beer places sell scavenge or lock up the O2 from the headspace. Something they put in the seal or somewhere gets activated by the water in the beer and causes a chemical reaction that uses up much of the O2 in the headspace.
 
Not only is the yeast woke up and embarking on another fermentation process by the priming sugar or wort, the bottle caps themselves that many beer places sell scavenge or lock up the O2 from the headspace. Something they put in the seal or somewhere gets activated by the water in the beer and causes a chemical reaction that uses up much of the O2 in the headspace.
Theoretically yes, practically it didn't work. More of a sales thing than a real benefit.
 
Theoretically yes, practically it didn't work. More of a sales thing than a real benefit.
Maybe. But since we often worry about things that are just marginal gains, then this is perhaps one additional marginal gain. Certainly as we bottle we are disturbing our beer and it's probably gassing off some of the dissolved CO2 so that also probably purges some of the O2 out of the bottle headspace too.

I'd be interested in the "practically it didn't work" part. Are you saying they don't scavenge or tie up any O2? Though I might concede that with normal bottling practices they don't make much difference over non-scavenging bottle caps.

Again, marginal gains maybe. But add up enough marginal gains and they might amount to something.
 
I've seen those caps... How do you get them sanitized??
Because the O2 scavenging stuff will be used up or washed out by starsan solution or any other water in contact with the caps...
 
Maybe. But since we often worry about things that are just marginal gains, then this is perhaps one additional marginal gain. Certainly as we bottle we are disturbing our beer and it's probably gassing off some of the dissolved CO2 so that also probably purges some of the O2 out of the bottle headspace too.

I'd be interested in the "practically it didn't work" part. Are you saying they don't scavenge or tie up any O2? Though I might concede that with normal bottling practices they don't make much difference over non-scavenging bottle caps.

Again, marginal gains maybe. But add up enough marginal gains and they might amount to something.
It just doesn't seem to do anything, compared to bottles with standard caps. Limiting the headspace had a huge effect, switching to these wannabe oxygen scavenging caps did nothing. There are pictures here, somebody did all the work.
 
It just doesn't seem to do anything, compared to bottles with standard caps. Limiting the headspace had a huge effect, switching to these wannabe oxygen scavenging caps did nothing. There are pictures here, somebody did all the work.
I've seen various "experiments" some homebrewers have done and the pictures with their results. But there isn't any factual information about whether or how much O2 is scavenged or locked up by the caps.

All the so called results don't really answer the question if the caps remove O2 from the headspace or not. My response isn't about whether they are effective or not compared to other ways. Just simply if they do or don't remove O2 from the headspace.

So far I'm going to assume that they do remove some. And since the O2 in the head space is likely less than 21% the volume of the headspace, they wouldn't have much to remove.
 
FWIW: Oxygen Absorbing Bottle Caps at morebeer.com

YMMV based on specific brand / product (?)

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I've seen various "experiments" some homebrewers have done and the pictures with their results. But there isn't any factual information about whether or how much O2 is scavenged or locked up by the caps.

All the so called results don't really answer the question if the caps remove O2 from the headspace or not. My response isn't about whether they are effective or not compared to other ways. Just simply if they do or don't remove O2 from the headspace.

So far I'm going to assume that they do remove some. And since the O2 in the head space is likely less than 21% the volume of the headspace, they wouldn't have much to remove.
If of six bottles two are with standard cap and standard head space, two are with oxygen scavenging cap and standard head space and two are with minimum headspace and standard cap and only the last two don't turn brown, then that's quite relevant if you ask me.
 
But then, what is the difference in racking to a secondary (and bottling directly from the secondary to bottles, that is, just one transfer) Vs racking to a bottling bucket (just one transfer)?
If you are looking for a "best practices" process for bottling, it may involve a number of trade-off between tools, techniques, and items.

For example:
  • oxygen avoidance: avoid transfers (e.g. bottle directly from the fermenter)
  • oxygen avoidance: avoid 'leaky' transfers (e.g. don't use broken auto-siphons)
  • oxidation minimization: minimize head space (trade-off vs bottle bombs)
  • oxidation minimization: additions at bottling time (e.g. ascorbic acid? others?)
  • oxidation minimization: refrigeration?
Commerical craft beer packaging may offer some insights as to what combinations of thing work? What type of bottle caps are used? Is the beer kept cold after packaging? etc.
 
I don't see much difference after all... but I'm just a newbie

I think a big difference is the time of oxygen exposure. My (rather crude) understanding is that oxygen uptake is a slow process. You will get a lot more oxygen in the beer leaving it for a week in a carboy with a headspace full of air than you will over the 20 minutes your beer is in a bottling bucket.

Personally, I keg 75% of my beers, and when I bottle I almost always bottle directly from the fermenter (without a transfer to a secondary).

I've seen those caps... How do you get them sanitized??

I don't know if the oxygen absorbing caps really do anything. I recall a study by New Belgium (I think) where they lost hop flavors when using oxygen absorbing caps. I tend to use them partially hoping that they work and partially because that is what many stores sell. I just dunk them into a small cup of StarSan before capping the beer. The caps should be sanitized before they touch beer. Some people just skip the sanitization step.
 
If of six bottles two are with standard cap and standard head space, two are with oxygen scavenging cap and standard head space and two are with minimum headspace and standard cap and only the last two don't turn brown, then that's quite relevant if you ask me.
Yes but that still doesn't really answer the question of whether they scavenge a significant amount of O2. Also seems to me that the results don't necessarily mean that there isn't some other reason for the brown. So some actual determination of their O2 scavenging ability might cast some better light on what the results even mean.
 
@Miraculix @hotbeer : if either of you has links to prior topics, that would help with the discussion. In those topics, I would be curious about how the oxygen scavenging caps were used vs how they are supposed to be used.
I don't have any links other than from sellers in beer and other sellers in the food industry saying they scavenge O2. So as to how much is bound up, I don't know. I currently don't have any reason to not believe them, but I do remain skeptical but am unwilling to call them a sham.

Besides, everyplace I've purchased caps from, they are the only type of crown cap they offer.
 
If you use plastic bottles, after you fill them squeeze the bottle so the liquid level is right at the brim, then screw on the cap. When the beer starts carbonating, the bottle will inflate again with CO2 and will have a normal headspace.
 
In a thread on another forum, I saw a reference to the patent number. I skimmed this and read a few sections. If you search for the term "beer" you will likely find the most relevant sections.
https://patents.google.com/patent/US5143763A/en
The patent contains some results of various tests, often showing a significant reduction in the oxygen in the headspace and in the beer. Though it looks like the tests are more designed to help with a potentially small amount of air that might get into a commercially bottled beer, and not the typical amount of air in a standard homebrew filled bottle. Here is the test used for several beers. They injected 1 cc of air into the headspace of a purged bottle.

A crown of a commercial beer (the bottle capacity: 633 ml) was opened, and then the headspace of the bottle was purged by foaming beer, and then 1 cc of the air was injected into the headspace for equalizing to normal beer, and thereafter, the above crown with the oxygen absorbable disc 25 was immediately attached to seal the bottle.

This tends to confirm my gut feeling about stuff like oxygen absorbing caps, or adding anti-oxidants (like metabisulfite or ascorbic acid) to a bottle. Those types of steps can help to clean up small amounts of oxygen, but they are not enough to overcome a full headspace full of air.

The patent has a potentially long list of potential oxygen absorbers that could be used (including ascorbic acid, and sulfite). I am curious what is used for bottle caps. Do they work just like adding a tiny amount of ascorbic acid to a bottle?

12. The oxygen scavenger defined in claim 1 wherein said oxygen absorbent composition is selected from a member of the group consisting of ascorbic acid, ascorbic acid salt, isoascorbic acid, isoascorbic acid salt, gallic acid, gallic acid salt, tocopherol, hydroquinone, catechol, resorcine, dibutylhydroxyltoluene, dibutylhydroxyanisole, pyrogallol, sorbose, glucose and lignine, iron powder, activated iron, ferrous oxide and iron salt, sulfite, thiosulfate, dithionite and hydrogensulfite, oxidation-reduction resin and polymer metallic complex, zeolite and activated carbon.
 
As others have noted, if you get a carboy with a spigot you can skip the bottling bucket too.

With few exceptions, I bottle all of my beers right from the primary fermenter. Especially any beer with a ton of hops. If you transfer an IPA or NEIPA to the bottling bucket you will oxidize it.
 
My interest in these topics is this: as I start brewing larger batch sizes (2.5 gal), I'm looking for a 'benchmark' bottling process that will keep the packaged beer fresher longer.

For those that bottle, and have a bottling process that keeps the beer good 90 days (3 months) after bottling, are you willing to share the complete bottling process?
 
I am not sure any process will keep a NEIPA fresh for three months, but I spent two years figuring out how bottle and not to oxidize them. I use that process for all of my beers now.

As mentioned, do not ever transfer. I bottle right from the fermenter into bottles with the sugar already in them. Cap immediately using the oxygen absorbing caps (whether they work or not). Arguably, bottling this way helps prevent oxidation because the yeast scavenges oxygen as the beer carbonates.

I do not purge the bottle headspace. It probably can't hurt, but it also means not capping quickly...

I don't ever open the carboy, unless I dry hop. If I do, then I have a can of CO2 to spray on top. Not sure if that really works, but it can't hurt.

I use a Tilt to monitor the gravity, so no need to open the carboy.

BTW, the first and last few bottles that I bottle this way tend to have some trub, so I mark those as for my own consumption only. (They are usually perfectly fine, though sometimes the excessive yeast causes them to over carbonate.) The beers I bottle in the middle are for competitions or to give to friends.
 
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I spent two years figuring out how bottle and not to oxidize them. I use that process for all of my beers now.
How long are those bottles good for?

I don't ever open the carboy, unless I dry hop. If I do, then I have a can of CO2 to spray on top. Not sure if that really works, but it can't hurt.
How long does the beer stay in the fermenter?
 
How long are those bottles good for?


How long does the beer stay in the fermenter?

Well, I am currently enjoying my Belgian Dubbel and a Quad that I bottled a year ago... So the bottles are good for years if they are the style that ages well. On the other hand, I would drink up my NEIPA's and IPA's within two months, because hoppy beers don't age well using any process.

I generally keep my beer in the carboy for three weeks. One week to ferment and two weeks to condition and have the yeast flocculate.

I have certainly pushed it to two weeks total sometimes, but I don't cold crash, and I find there is too much yeast left in suspension - which risks over carbonating the bottles. I recently got away with it when submitting a beer for competition that was going to be evaluated by the judges soon (it won a blue ribbon/first place). But after a 2+ months that same beer is now a bit over carbonated.

As mentioned, I use a Tilt, so it's easy to know when I've hit FG. I find that the Tilt sometimes misses the OG, but it's generally pretty accurate with FG. I often check the FG with a hydrometer too, if I want to know for sure. But the great thing about a Tilt is that you can tell when fermentation is done when the SG doesn't move for a few days.
 
For those that bottle, and have a bottling process that keeps the beer good 90 days (3 months) after bottling, are you willing to share the complete bottling process?
This is something I have been slowing working toward, and I hope to put more effort toward it in the next few months.

Personally, I have found that leaving the standard headspace in a bottle will cause oxidation issues (even with bottling directly from the fermenter and adding sugar to individual bottles). This was reconfirmed to me recently. I made a 3 gallon SMaSH with Maris Otter and BRU-1 hops fermented with 3 yeasts. When I cycled back to them after about 2 months after bottling, they were rather dull. The US-05 bottles were darker than the Voss or Lutra ones, but they all showed tell tale signs of oxidation flavors. These bottles were kept at a room temp around 70F after 2 weeks of conditioning at 75F.

The most clear first step I would recommend is to reduce the amount of headspace in a bottle. A rough estimate is that a standard full has about 20 cc of air in the headspace. A high fill that reduces that down to 10 cc or 5 cc means 50% to 75% of the air is removed. Purging the headspace with CO2 is another option that I have done with demonstrated success. I have also demonstrated success using PET bottles and squeezing to purge the headspace. I have read that long term storage in PET bottles can be problematic, but I cannot confirm that.

Keeping bottled beers cold once they are carbonated is likely another "easy" step that will significantly reduce oxygenation damage. I have not played around with this much myself since I don't have a lot of fridge space for bottles. I have seen a number of examples of people with fairly sloppy techniques that are able to keep hoppy beer fresh via cold storage.

I tend to think that once you have taken steps to reduce oxygen exposure through fermentation, and have reduced the amount of oxygen in the bottle, then you can look to steps like oxygen absorbing caps, anti-oxidants, or maybe adding fresh yeast when bottling.

A couple weeks ago, when bottling 4 gallons of experimental beers, I played around with adding ascorbic acid and potassium metabisulfite at bottling combined with high filling. I did some maths to come up with a solution of sugar + aa + pmb that I would add 5 ml to each bottle. My goal was to fill the bottles a little high leaving 10 cc of headpace, add 5 ml of solution, leaving about 5 cc of headspace. For each 1 gallon batch, I also filled 3 bottles to the same 10 cc then dropped in a sugar cube (so no aa or pmb in those bottles with a similar headspace).

These are likely not the best batches of beer to showcase oxidation. They are one gallon batches made with DME, with a small addition of Pahto hops, and fermented with a Belgian yeast. I have opened a few bottles that used the solution with aa and pmb. They are carbonated and taste okay. A bit of a harshness that I think is from the clove character from the M41 Belgian Ale yeast I used. The beers are young and I have not opened any of the sugar cube bottles. My goal with these was more to get some experience with the process and ensure it worked well enough before trying it on a more expensive beer like an NEIPA.
 
I don't brew NEIPAs, I buy them when I go to a brewpub or taproom. When I brew other hoppy beers, I drink them quickly. I haven't done anything with dry hops yet. So I wouldn't necessarily know if I have an oxidation problem as long as it's not too bad. But here's my process, which tries to minimize O2 just because it at least should be good practice:

1) I ferment my beer in a bucket with a tightfitting but not quite airtight lid (good snap fit but no gasket.) I just bought some more 'S' type airlocks and grommets for the lids so I don't have to burp them when fermentation is really active or risk having the lid blow off. That could really be a mess and I would never hear the end of it from my wife. ;) I use a Tilt hydrometer to monitor the fermentation, so I know when it's done and I don't have to open the lid until it's finished. (If I'm using a top-cropping yeast, sometimes I will open it once on about day 2 to harvest the yeast.) Before I got the Tilt, I just let it go for 2 weeks for most ales or 3 weeks for strong ones. I haven't been brave enough to try a lager yet. Now with the Tilt I find that they are usually finished in 1 week.

2) I transfer the beer to a carboy full almost all the way to the top, and I add a tablespoon or two of sugar. Add the airlock, and let it sit for another week or so to clear. This step is mainly to get the beer off of the trub. I do BIAB and get a lot of grain dust and some hop pellet junk in the fermenter and I don't want it getting in the way when I bottle. The sugar is to activate the yeast again; the CO2 forces the air out of the headspace and the yeast metabolize the dissolved oxygen. That's my theory anyway. Some of the headspace oxygen makes it into the beer, but hopefully that gets eaten by the yeast too. I call this a "brite tank" rather than a secondary fermenter. I guess it would be a secondary if I added fruit or something at this step.

I've started adjusting my recipes so I will have a little too much beer for the carboy, so if I miscalculate it will still be enough to fill it all the way. If I have enough excess, I bottle it (that bottle will have a *lot* of sediment.) Then I drink whatever's left.

3) I bottle directly from the carboy using a racking cane. The filler I use leaves too much headspace (they probably all do), but its foot-valve is not spring loaded so I can press it to the inside mouth of the bottle and finish filling to leave just a little headspace. With plastic bottles, I prime them individually before I fill, then I squeeze the bottles to get rid of all the air before I tighten the cap. With glass bottles, I prime individually with sugar after filling, which usually causes them to foam up from the dissolved CO2. The foam displaces the air in the headspace. I used to prime 12 and 22 oz glass bottles with small Domino Dots sugar cubes and 500ml plastic bottles with large C&H sugar cubes. Domino Dots are not available anymore, but once I started measuring granulated sugar with a spoon and small funnel, that's actually faster.

It took a while for my process to evolve into this. It might be ridiculous and I could be fooling myself, but the beer is good.
 
I would drink up my NEIPA's and IPA's within two months, because hoppy beers don't age well using any process.
(Visual +1): This seems to be a solid (and simple) approach.

I made a 3 gallon SMaSH with Maris Otter and BRU-1 hops fermented with 3 yeasts. When I cycled back to them after about 2 months after bottling, they were rather dull.
What was the hop schedule (hop stand? dry hop)?

More generally: if we can't measure the amount of oxygen ingress just before bottling time, are whirlpool or dry hop additions an indication of batches that may more prone to oxidation after bottling?

The US-05 bottles ... [vs ...] Voss or Lutra
Is yeast used for bottle carbonation a factor here?

For me, US-05 is a slower during fermentation and during bottle conditioning. I recently brewed a small batch BIAB brown ale with S-33. 7 days fermentation, 2 days bottle conditioning, and it was carbonated [1] [2] [3].

If the yeast consume O2 as part of bottle conditioning, faster may be better.

2) I transfer the beer to a carboy full almost all the way to the top, and I add a tablespoon or two of sugar. Add the airlock, and let it sit for another week or so to clear. This step is mainly to get the beer off of the trub. I do BIAB and get a lot of grain dust and some hop pellet junk in the fermenter and I don't want it getting in the way when I bottle. The sugar is to activate the yeast again; the CO2 forces the air out of the headspace and the yeast metabolize the dissolved oxygen. That's my theory anyway. Some of the headspace oxygen makes it into the beer, but hopefully that gets eaten by the yeast too. I call this a "brite tank" rather than a secondary fermenter. I guess it would be a secondary if I added fruit or something at this step.
I have seen this idea (transferring to a narrow neck carboy, then adding sugar to purge O2) a couple of times over the last year.

Maybe something was "lost" with the introduction of wide neck fermenters? 🤷‍♀️



[1] bottle conditioning done in a beverage cooler with water at 75° F.
[2] For best results, bottles should have been chilled (40° F) for a day (or two).
[3] Next time I brew this recipe, I may leave it in primary for another week, but that's not the point.
 
What was the hop schedule (hop stand? dry hop)?

Each 1 gallon batch got a very small addition (0.21 oz) of Pahto hops at 10 minutes (total boil time was 10 minutes).

If the yeast consume O2 as part of bottle conditioning, faster may be better.

It could definitely be a factor and my couple bottles seemed to point at that. I wonder if part of @SRJHops success is that he is using a Tilt to monitor fermentation which might mean he can bottle beers a little earlier while there is a bit more active yeast.
 
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