O2 free transfer paranoia ???

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Willy

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Watching a Guinness stout clone homebrew after a pour ... I noticed a line of CO2 bubbles form at the bottom of the glass. So I looked up - which is a heavier gas, CO2 or Nitrogen? Then I did the same for O2. And guess what, CO2 is heavier by far than either oxygen or nitrogen.

Before I did O2 free transfers using corny keg posts, I just carefully dropped a tube into the bottom of a corny keg, and pushed a little CO2 into it to clear out any O2. While not perfect (might be a little churning of gases... But who knows??) I never had a problem with O2 spoiling the beer. I used this method so many times and it always worked fine.

Doing the O2 free transfer can be soooo slow, and also "blind" since I have no idea how much is in the corny other than guess by weight. So, I think I am just going back to my old method... Just carefully fill the corny with beer from the bottom up and purge with CO2 from time to time. I place saran wrap over the lid and just leave enough room for the tube to go in, and let out gas.

Anyway... I think most people, myself included... Get a little paranoid with O2 infiltration at racking... If you are careful it can be done well without all the fuss. CO2 sinks... And is heavier than O2. So ... Slow movements, keep the gas area as still as possible, fill , bottom up and down a purge of CO2 from time to time. My own experience is - you will be fine.
 
Your tap water has dissolved oxygen in solution this is removed when the water is boiled. Transferring the beer to the keg will not add much back if the transfer is gentle and the area of beer in contact with oxygen is small. Time in contact with oxygen is also important so something like 15 minutes is irrelevant. Once the keg is filled purge the headspace with CO2 and purge 2 or 3 times.
 
If you were completely happy with open transfers, you don't need our approval to go back. The speculation about gas weights and all that doesn't account for the way gases behave. CO2 doesn't "fill up" the keg. It mostly co mingles as if there was nothing else already in there. If you keep adding enough CO2, eventually collisions will push some of the nitrogen and O2 out, but never all of it and it doesn't prevent new oxygen from coming in the open top as you fill.

I think the problem many people have is an intuition that CO2 molecules act like glass marbles while O2 molecules act like small helium balloons. If that were true, we'd all be dead.

Anectodes are generally meaningless, but given the improvements I've seen in my beer, there's no way I'd go back to open fills. The brewing industry at large knows that oxygen destroys beer quality. If you don't think the juice is worth the squeeze, it's your beer.
 
If you were completely happy with open transfers, you don't need our approval to go back. The speculation about gas weights and all that doesn't account for the way gases behave. CO2 doesn't "fill up" the keg. It mostly co mingles as if there was nothing else already in there. If you keep adding enough CO2, eventually collisions will push some of the nitrogen and O2 out, but never all of it and it doesn't prevent new oxygen from coming in the open top as you fill.

I think the problem many people have is an intuition that CO2 molecules act like glass marbles while O2 molecules act like small helium balloons. If that were true, we'd all be dead.

Anectodes are generally meaningless, but given the improvements I've seen in my beer, there's no way I'd go back to open fills. The brewing industry at large knows that oxygen destroys beer quality. If you don't think the juice is worth the squeeze, it's your beer.
My top is not open... The top is covered in saran wrap, with a small space for the tube and to let gas out (no oxygen comes in... I have a border wall :) haha). The pressure in the corny is slightly higher so air is exiting the corny to counteract the beer coming in and displacing the CO2 in the keg.

I can't tell any difference using this method... And yeah, I have tasted beer that is been poorly treated during transfer... It tastes a little flat tasting for lack of a better word, despite being carbonated.

I am from Milwaukee, so I care about my beer more than normal people do. It is in the blood. In my experience, if you are careful about it, you can do a good transfer and not ruin it by oxygen exposure. If it didn't work... I would have abandoned the practice long ago. And probably not be brewing for 20+ years, because I like good beer.
 
Everything is on a gradient scale. The method you describe is not as good as a liquid displacement purge and closed transfer but it's not as bad as picking up and pouring the beer in. Where it lands on that scale is probably different every time you perform it. Then there are all the factors about the beer styles and their likelihood of oxidation making itself known in your drinking timeframe.

Stepping back from this specific topic to look at the big picture. The beer in the glass is the result of 100 different processes that can be performed optimally or suboptimally. I try to be as proactively optimal as possible knowing that I will fail on some of them due to circumstances outside of my control and/or understanding. It gets me better beer despite my common errors.

Being in a homebrew club that collectively went from doing pretty well at competitions to absolute domination in a few years shows the contagion of best practices. We get to see members making their beer better, one mistake correction at a time. Oxidation is a big one, in perhaps five big ones. YMMV.
 
i have to agree my beer is much better now that i close transfer
and when i get lazy and dont or when i have a little left over in the FV that dont fit in the keg and tranfser that without closed transfer the difference in taste and shelf life is very clear.
 
Everything is on a gradient scale. The method you describe is not as good as a liquid displacement purge and closed transfer but it's not as bad as picking up and pouring the beer in. Where it lands on that scale is probably different every time you perform it. Then there are all the factors about the beer styles and their likelihood of oxidation making itself known in your drinking timeframe.

Stepping back from this specific topic to look at the big picture. The beer in the glass is the result of 100 different processes that can be performed optimally or suboptimally. I try to be as proactively optimal as possible knowing that I will fail on some of them due to circumstances outside of my control and/or understanding. It gets me better beer despite my common errors.

Being in a homebrew club that collectively went from doing pretty well at competitions to absolute domination in a few years shows the contagion of best practices. We get to see members making their beer better, one mistake correction at a time. Oxidation is a big one, in perhaps five big ones. YMMV.
Agree with all you said 100%. Great beer is all about a million little things. And... I believe this... The love you put into making beer is crucial to the process, because you do those little things with joy and your whole heart. That matters as you avoid shortcuts.

Not everyone has the capability of doing O2 free transfers... And I do think some methods are much better at reducing O2 contamination by methods that emphasize
1) put the tube all the way to the bottom of the keg.
2) purge keg with co2: before you start transferring
3) cover top with saran wrap to reduce air disturbances which can bring in unwanted O2.
4) put on the top and purge well 3 or 4 times to clear the headspace.
5) time is of the essence. Finish and clear up headspace with CO2. Even if some O2 came in, it doesn't have time to sit in the keg after a good round of purging.
 
Good posts here. In the end, trying hard(er) is up to the brewer. Let go of the weight of CO2 gas is heavier myth and you will be better off! The O2 conversation is always tough because keeping oxygen out is difficult. Many do not want to go to the extreme which is perfectly fine. But the science and proof is there - Keep O2 out and your beer is better and lasts longer.

If the transfer takes to long use a larger diameter transfer hose. I made my jumper out of the largest EVA Barrier tubing (9.5mm) and it helps the transfer speed. One thing that is a positive is that you do not need to baby the transfer. Just get it going (I use gravity) and leave for a while.
 
Agree with all you said 100%. Great beer is all about a million little things. And... I believe this... The love you put into making beer is crucial to the process, because you do those little things with joy and your whole heart. That matters as you avoid shortcuts.

Not everyone has the capability of doing O2 free transfers... And I do think some methods are much better at reducing O2 contamination by methods that emphasize
1) put the tube all the way to the bottom of the keg.
2) purge keg with co2: before you start transferring
3) cover top with saran wrap to reduce air disturbances which can bring in unwanted O2.
4) put on the top and purge well 3 or 4 times to clear the headspace.
5) time is of the essence. Finish and clear up headspace with CO2. Even if some O2 came in, it doesn't have time to sit in the keg after a good round of purging.
Describe your fermentation/keg setup or post a picture. Maybe it can be improved?
 
Describe your fermentation/keg setup or post a picture. Maybe it can be improved?
Right now I have just a few vessels capable of doing an oxygen free transfer. (A CF10, and a few large corny kegs)... The other fermenters are just 7 g buckets.

I do O2 free transfers using the corny kegs or the Spike CF-10. The buckets I use the method described above... And I put a tube in the blowoff hole on the bucket lid that is attached to a balloon filled with CO2. I have not noticed any difference in beer quality based on which fermenter I'm using or the transfer method.
 
Then spigot + gravity = closed transfer. I run the first bit out of the fermenter into a soda/water bottle and pull the QD while flowing to purge all of the O2 out before then hooking up to the keg. I then then hook up a return from the keg back into the fermenter to make a closed loop.

Do you fermentation gas purge your kegs? Closed transfers can not get much easier with the whole setup. Let the fermentation gas purge the keg, hook up the transfer line, run a bit off and connect the keg. This is as easy as when I did the old method of opening keg and much better.

Here is a video I made about my process (which was taught to me by fellow brewers). -

Hope it can help in any way.
 
I do closed keg transfers with my Fermonster fermenters. I adopted the process when I started thinking about brewing NEIPA style beers. There were times when I thought "it is just a Irish Ale or Porter, so no need for the extra time to purge and transfer." Maybe it is just my bias, but I swear those beers started to take on some oxidation character after a few months in the keg. These days I do all my beers with a closed transfer. Yeah, it takes 10 minutes to purge a keg and the transfer takes an extra 10 minutes, but it is an easy step that I know will help the quality of my beers (or if there are flaws with the beer, I won't be able to blame my sloppy kegging process).

My video:
 
I had an interesting problem while doing an O2 free transfer - I was getting all kinds of little bubbles in the beer line during transfer. Huh?

Finally figured it out and I suspect it might happen to others - so, make good beer and learn from my mistake.

The hose was a little too big for the spigot on my fermenter bucket... And air was getting "sucked in" the line where the hose was supposed to be real airtight at the spigot. Ooops. Thankfully... I had some Irish and German and Czech friends over along with some local rebels and we finished it off joyfully before the dreaded cardboard taste set in. But it could have been a disaster!
 
I had an interesting problem while doing an O2 free transfer - I was getting all kinds of little bubbles in the beer line during transfer. Huh?

Finally figured it out and I suspect it might happen to others - so, make good beer and learn from my mistake.

The hose was a little too big for the spigot on my fermenter bucket... And air was getting "sucked in" the line where the hose was supposed to be real airtight at the spigot. Ooops. Thankfully... I had some Irish and German and Czech friends over along with some local rebels and we finished it off joyfully before the dreaded cardboard taste set in. But it could have been a disaster!
This happens on racking canes too. If the hose is just pushed onto the top of the cane, the bend on the cane breaks the seal a tiny bit sometimes. I would just flick the hose a few times to move the bubbles. If they come back, the seal is not so good there. A clamp of some sort generally fixes it. I have a better sealed racking cane and cap setup now that I use with a slight bit of CO2 for a pressurized transfer when using carboys.
 
I have found that if you brew beers that are largely defined by hop character (IPAs), the oxygen thing is real and can make the difference in good beer vs really good beer. So the extra PitA and equipment are warranted. Other, more malt forward beers and beers that have a lot of yeast defined character are not so sensitive. (European styles). I expect those to be more complex flavor-wise and couldn't tell a diacetyl from a pterodactyl most of the time. Saisons may be the exception there, but as long as I finish them with Saaz, they don't mind a swift open transfer either. Purge headspace twice and force carb and there ya go.

Also, I secondary unless the yeast I'm using flocs like silly putty. That's an easy airless transfer since I can usually see the level in the vessel. Not a fan of drinking past the keg mud.

Of course I have to footnote here by saying this all comes from my humble subjective opinion. I don't compete and the judge of my beers is pretty much me and maybe a small group of folks highly influenced by free beer. Quality is judged relative to previous versions of my own beer, other home brewers I share with and vs local craft brewery fare and examples of what may be over-aged and mistreated imports that are not in prime condition. But lots of them. And over a long period.

Does that jive with the experience of anybody here or am I just blissfully ignorant and everybody's eye-rolling me?
 
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The batch was for an Americanized light Brown ale. I agree - malt forward beers are not as susceptible as high hop beer, lagers, pilsners & blondes.
 
I have found that if you brew beers that are largely defined by hop character (IPAs), the oxygen thing is real and can make the difference in good beer vs really good beer. So the extra PitA and equipment are warranted. Other, more malt forward beers and beers that have a lot of yeast defined character are not so sensitive. (European styles). I expect those to be more complex flavor-wise and couldn't tell a diacetyl from a pterodactyl most of the time. Saisons may be the exception there, but as long as I finish them with Saaz, they don't mind a swift open transfer either. Purge headspace twice and force carb and there ya go.

Also, I secondary unless the yeast I'm using flocs like silly putty. That's an easy airless transfer since I can usually see the level in the vessel. Not a fan of drinking past the keg mud.

Of course I have to footnote here by saying this all comes from my humble subjective opinion. I don't compete and the judge of my beers is pretty much me and maybe a small group of folks highly influenced by free beer. Quality is judged relative to previous versions of my own beer, other home brewers I share with and vs local craft brewery fare and examples of what may be over-aged and mistreated imports that are not in prime condition. But lots of them. And over a long period.

Does that jive with the experience of anybody here or am I just blissfully ignorant and everybody's eye-rolling me?
There is wiggle room for sure on this topic. In my experience, low oxygen practice really helps aroma. So I follow it for all styles.
 
malt forward beers are not as susceptible as high hop beer, lagers, pilsners & blondes.

Or, we might actually like a bit of it. Maybe what we call "smoothing out" the flavors is simple oxidation. We like that in dark beers but not the light ones. I sometimes wonder if allowing a little oxidation / splashing might help an imperial stout "age" faster.
 
Or, we might actually like a bit of it. Maybe what we call "smoothing out" the flavors is simple oxidation. We like that in dark beers but not the light ones. I sometimes wonder if allowing a little oxidation / splashing might help an imperial stout "age" faster.
Possible. Trust me - I don't know much about anything, other than I really don't know. Ha.
 
Style-dependent, absolutely. I'm a firm believer the "flavor" of English beer is oxidation. Many commercial beers are deliberately oxidized. Some oxidative flavors are good, some are bad. Even certified beer judges have strengths and weaknesses when it comes to off-flavors where everyone has a different detection threshold. I'm really good at picking out acetaldehyde, DMS (and other sulfur compounds), and nonenal but I'm not very good with diacetyl. I went to a fellow homebrewer's house who was doing open transfers and all of his light beers were loaded with acetaldehyde but he had absolutely no idea. The second I got him doing closed transfers, the problem went away. Not everyone is trying to win homebrew competitions like us obviously, but even if I'm brewing for myself, I don't want my beers to have diacetyl, even if it's below the threshold I can detect, because I want everyone to enjoy my beer, even my friends who are very sensitive to diacetyl.

I think claiming that open transfers do not make any difference at all is just silly. It just plain does. Low oxygen breweries like Sierra Nevada and Weihenstephaner would not practice what they do if they did not have sensory and actual studies with GC/MS data to back it up.
 
Style-dependent, absolutely. I'm a firm believer the "flavor" of English beer is oxidation. Many commercial beers are deliberately oxidized. Some oxidative flavors are good, some are bad. Even certified beer judges have strengths and weaknesses when it comes to off-flavors where everyone has a different detection threshold. I'm really good at picking out acetaldehyde, DMS (and other sulfur compounds), and nonenal but I'm not very good with diacetyl. I went to a fellow homebrewer's house who was doing open transfers and all of his light beers were loaded with acetaldehyde but he had absolutely no idea. The second I got him doing closed transfers, the problem went away. Not everyone is trying to win homebrew competitions like us obviously, but even if I'm brewing for myself, I don't want my beers to have diacetyl, even if it's below the threshold I can detect, because I want everyone to enjoy my beer, even my friends who are very sensitive to diacetyl.

I think claiming that open transfers do not make any difference at all is just silly. It just plain does. Low oxygen breweries like Sierra Nevada and Weihenstephaner would not practice what they do if they did not have sensory and actual studies with GC/MS data to back it up.
I totally agree with (most of) this. And if I was who you were responding to, thank you for your response. You are more of a perfectionist than I am, but you understand. In a perfect world with an unlimited budget and a motivated nature, I would build the perfect oxygen avoidance system for all my brews. BUT - If English beer flavor is oxidation, then screw all you guys cause I'm where I need to be.:) When the beer gets stale, my tune will change. Until then, <pbthlllt> :rock:
 
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It is paranoia. You don't want to splash any more than necessary, but push transfers are a fad and not needed. No one 10 years ago was doing it. And lots of good homebrew was made. Better with it? Nope. Yes, my opinion. If you do try and do O2 free transfers, knock yourself out.
I will say here that to the question "Better with it?" my answer would be "Yes". I'm just not into this enough to strictly adopt practices that make me dread transferring.
 
FWIW, there are threads on the topic that are more than 10 years old.
And eventually there will be threads 100 years old. Unless future humans realize that, in order to travel the galaxy at any speed approaching that of light, we must shed our physical forms and have no mass. In which case beer would probably not be that big a deal.
 
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I will say here that to the question "Better with it?" my answer would be "Yes". I'm just not into this enough to strictly adopt practices that make me dread transferring.
The closed transfer does take a little longer, but for me, it’s a joy sitting there sipping on a cold beverage and watching all that brew going through the line into a keg that will soon make it to my cooler!
Yes, the last one was a bit agonizing; I had decided to abandon the old vinyl transfer hoses and use eva barrier line. Between the small id and a duotight connector not sealing tightly onto the fermenter, it took FOREVER!
However, I have a package of the large diameter eva hose sitting at the PO right now waiting to be picked up and outfitted with my standard barbs and connectors.
When it goes as usual, I don’t dread the transfer at all; I actually enjoy it. 🤷🏻‍♂️
 
When it goes as usual, I don’t dread the transfer at all; I actually enjoy it. 🤷🏻‍♂️
Sometimes I think it comes down to convenience and even personality. If it's a rainy day and I got nothing else going on, I will dig out the gear and the tanks and setup for the push. If it's nice out and I just need that brew in the keg so I can get back to hanging out - it's quick fill and purge.
Also, I'm not the scientific or perfectionist type. I know this is the perfect hobby for someone who is and I kind of envy that - but I can be ok with good enough for govmt work.
 
Also, I'm not the scientific or perfectionist type. I know this is the perfect hobby for someone who is and I kind of envy that - but I can be ok with good enough for govmt work.
We’re in the same boat there. I’m glad this hobby has room for the scientific/perfectionist; I can learn a lot from them. However I am just here to make a decent beer and enjoy doing it; I don’t want to make work out of it. I realize that the definition of “work” is very subjective.
I actually brewed for decades without ever taking an OG or FG; I figured I’d get what I would get and shrug it off. I have still yet to measure my mash ph even though I have a brand new unused meter still in the box. (Since it hasn’t been my routine, I kinda forget about it until after the brew.) I filter my water, but do nothing else to it. I can hear heads popping right now at my blasphemies. 🤣

I just look at my lapses as new territories for future exploration and development; I will eventually go there, but in the meantime I am going to just RDWHAHB!
 
@Willy, a simple improvement to the process for your bucket transfers could be to put a ball lock on the end of your transfer hose and connect it to the out port on the corny. Eliminates the need for saharan wrap because you can put the corny lid on and just vent through the PRV. Also eliminates having to put the hose into the fermenter.
 
@Willy, a simple improvement to the process for your bucket transfers could be to put a ball lock on the end of your transfer hose and connect it to the out port on the corny. Eliminates the need for saharan wrap because you can put the corny lid on and just vent through the PRV. Also eliminates having to put the hose into the fermenter.
I have done that method and usually transfer out of a bucket via the spigot into the corny liquid out. Gas out goes to a sanitized starsan and water. I like the saran wrap mostly cuz it goes faster by far and also I can see the full line. I might just get a corny lid with 1 1/2" triclamp on the lid and put a sight glass on it.

Currently doing more 10 gallon batches - filling 2 corny kegs. One to serve immediately and the other to fully lager in peace or condition if it's a stout, ale etc.
 
I have done that method and usually transfer out of a bucket via the spigot into the corny liquid out. Gas out goes to a sanitized starsan and water. I like the saran wrap mostly cuz it goes faster by far and also I can see the full line. I might just get a corny lid with 1 1/2" triclamp on the lid and put a sight glass on it.

Currently doing more 10 gallon batches - filling 2 corny kegs. One to serve immediately and the other to fully lager in peace or condition if it's a stout, ale etc.

If your beer is cold while you are transferring you can see the fill level on the outside of the keg as condensation.
 
We’re in the same boat there. I’m glad this hobby has room for the scientific/perfectionist; I can learn a lot from them. However I am just here to make a decent beer and enjoy doing it; I don’t want to make work out of it. I realize that the definition of “work” is very subjective.
I actually brewed for decades without ever taking an OG or FG; I figured I’d get what I would get and shrug it off. I have still yet to measure my mash ph even though I have a brand new unused meter still in the box. (Since it hasn’t been my routine, I kinda forget about it until after the brew.) I filter my water, but do nothing else to it. I can hear heads popping right now at my blasphemies. 🤣

I just look at my lapses as new territories for future exploration and development; I will eventually go there, but in the meantime I am going to just RDWHAHB!
I have never checked a ph. And if I didn't have a Tilt I'd never know the gravity of anything. I just got it cause it integrated into the Grainfather process well. I gave up hydrometers long ago after the second one broke. I bought a cheap 2 roller mill last black Friday and have been crushing my own grain with the squeaky hand crank for about the last 3 brews. I can tell the new is gonna wear off of that process pretty quick and I'll be back to buying it milled again.
I'm a lazy brewer. But I'm good with that.
 
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I wonder how much excellent beer has been brewed by simple people whose process was to heat wet grain, add herbs, toss in yeast and then come back and check under the burlap every so often until it's time to drain it into an amphora.
 
I wonder just how bad a lot of that "beer" was...

Probably pretty bad. I know that when I first started so long ago we thought our beer was pretty awesome. Looking back though, nope, it was pretty bad compared to today.

I'd be interested to know if "good" breweries 100 years ago did something akin to closed transfers. I'd bet exposure to "air" was known to be different than not. If that's true, then this idea that being scared of O2 is a new thing we can ignore would be quite false.
 
I’m with you hoss, but “good” is a very relative term. There was a time, way, way back when Bud & PBR was a good (enough) beer for me.
What you described may be better than what was available elsewhere, but might be considered a dumper by many folks here.
I know some of the folks here are WAY more persnickety than I am about their process. I know that I have read and learned from them and my beer is better than it used to be.
The oxidation thing has been one area that has been a fairly easy fix with demonstrable improvements in my beer. Just tonight, I had a CO2 tank give out and I switched it, regulator and all out with one that I had just outfitted with new EVA barrier hose. I also just replaced the hose on the regulator I removed so that it is ready to go back in service better than before.

I am not looking to win ribbons or trophies. I am not striving to have everyone say my beer is best. I just want a good beer that I can produce reliably with a reasonable amount of effort. But at the end of the day, I just want to RDWHAHB
 
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