Best Method - Avoiding Oxygen While Transferring?

[mmmhops]

I've recently started to suspect that I'm picking up some oxygen during my transfer from primary to secondary/keg.

To transfer, I get a carboy cap with a stainless steel cane and push in CO2 until the transfer starts. This shouldn't be causing any issues.

The problem comes in with the receiving vessel. When transfering to a carboy, sometimes the bottom of the plastic transfer hose curls up, and I definitely feel like I'm picking up serious oxygen (even if I purge the carboy first).

Any suggestions on how to improve my transfer technique? What do the rest of you do to minimize oxygen pickup?

 

[day_trippr]

On the few times I rack between carboys I use a second cap and shorter dip tube that reaches to the very bottom of the receiving carboy with a section of plain tubing to connect between the dip tubes. When racking to keg I use the beer QD on the Out dip tube instead. In either case the longer dip tube and cap with the clamp goes on the sending carboy, and before moving any beer I flush the system end-to-end with CO2...

Cheers!

 

[TAK]

95% of the time, I'm going from primary to keg. I purge my keg by filling it 100% (and I mean 100%, this requires more attention to detail than you'd first think; I'm happy to explain how I do it, but will exclude that for now) with StarSan, and I push that out with CO2. Then, I have the out-end of my autosiphon tube setup with a liquid-out disconnect. I hook that up to the pressurized keg, which releases the pressure and purges the autosiphon. The business-end of the autosiphon is in the tip of the carboy during this, which adds some extra CO2 to the carboy. Then start the siphon, and hook up a gas-out disconnect to the keg to give the CO2 a place to go as it's replaced with beer. Done.

 

[jbaysurfer]

I'm not going to get into any debate over this, but I'll tell you my philosophy. 1) Transfer FEWER times. 2) Flush the "receiving" vessel with CO2. Whether it's a carboy or a keg.
3) Siphon carefully avoiding losing suction at all costs, re-establishing your siphon usually introduces air. 4) Make sure there's no leaks in your siphon 5) seek out ways to transfer under pressure.

#5 is last because it's usually the most involved, or most expensive (if you're doing it from a conical or something). But those are my beliefs on the subject.

 

[Woodbrews]

On the few times I rack between carboys I use a second cap and shorter dip tube that reaches to the very bottom of the receiving carboy with a section of plain tubing to connect between the dip tubes. When racking to keg I use the beer QD on the Out dip tube instead. In either case the longer dip tube and cap with the clamp goes on the sending carboy, and before moving any beer I flush the system end-to-end with CO2...

Cheers!

I use the exact same technique, but it looks like you have some nice refinements there -- can you explain how the mesh filter and stainless steel washer work? I assume it filters out the yeast & hop gunk and keeps it from getting sucked up the siphon? Does it ever get clogged?

Also, when using CO2 to transfer, all you need is about 1psi to get the siphon started. Once started, you can usually cut off the gas and the siphon continues.

Finally, can you explain what you mean by flushing the system end-to-end with CO2? Is the keg sealed when you transfer into it?

Thanks -- I'm always looking to improve my "best practices."

 

[sudsybrewer]

Why are you concerned? Are you picking up off-flavors that you think might be a result of oxygen exposure? It would be helpful to hear why you're thinking oxygen is a problem here.

Other thoughts: oxygen dissolves poorly into warmer liquids. Transferring before a cold crash rather than after might make a noticeable difference (or not...if this is even relevant to your situation in the first place...), but then you also end up transferring more gunk with the beer.

Cheers,

 

[day_trippr]

I use the exact same technique, but it looks like you have some nice refinements there -- can you explain how the mesh filter and stainless steel washer work? I assume it filters out the yeast & hop gunk and keeps it from getting sucked up the siphon? Does it ever get clogged?

I dry hop nearly every beer I brew with the exception of stouts and porters, and I almost always use free-swimming pellets in the primary fermenter (I only ever use a "secondary" for the stouts and the occasional brew that uses fruit).

After a couple of days cold-crashing everything is sitting pretty firmly on the bottom. I position the end of the dip tube so the washer is resting on the hop/trub/etc bed with the tube tip above. The washer keeps the mesh from collapsing, and there's enough material there that it's never clogged up, even when I was a little sloppy positioning the tube. When I get down to the last half gallon or so I'll typically slide the dip tube down to grab the last of the clear beer.

Also, when using CO2 to transfer, all you need is about 1psi to get the siphon started. Once started, you can usually cut off the gas and the siphon continues.

I've actually never had to go above an indicated .5 psi to get started. I'll leave the reg set there until it gets down to the last gallon when I'll close the shut-off and let gravity and the residual pressure finish up.

Finally, can you explain what you mean by flushing the system end-to-end with CO2? Is the keg sealed when you transfer into it?

I start with the sender dip tube positioned well above the wort therein, snap the beer QD on the keg Out post, and latch open the keg PRV. Then I open the CO2 shut-off and let the gas slowly flow through the carboy head space, out the dip tube, over to and down the keg Out dip tube, and up and out the keg PRV. I let the gas run until I'm satisfied that the O2 content has been significantly reduced if not eliminated, then lower the dip tube towards the bottom of the carboy and let the beer flow.

I've considered filling the keg with Star San and pushing that out as it seems compatible with my oxidation avoidance obsession but I haven't yet. I'll be kegging two batches in a week and a half and might try it then. I can push from the first keg to the second then push the second back to my Star San carboy, so it should be easy enough to do and it would take the guess work out of "How long to flush?"

fwiw, here's a close-up of the gas post. Makes the whole operation that much slicker...

Cheers!

 

[Woodbrews]

95% of the time, I'm going from primary to keg. I purge my keg by filling it 100% (and I mean 100%, this requires more attention to detail than you'd first think; I'm happy to explain how I do it, but will exclude that for now) with StarSan, and I push that out with CO2. Then, I have the out-end of my autosiphon tube setup with a liquid-out disconnect. I hook that up to the pressurized keg, which releases the pressure and purges the autosiphon. The business-end of the autosiphon is in the tip of the carboy during this, which adds some extra CO2 to the carboy. Then start the siphon, and hook up a gas-out disconnect to the keg to give the CO2 a place to go as it's replaced with beer. Done.

TAK - it sounds like you and day_trippr use a similar method. I've been using CO2 to siphon from a carboy to keg, and I fill the keg through the beer-out post (so that it fills from the bottom up), but I've never transferred into a sealed keg. Can you explain how you purge the keg and push out the StarSan with CO2? Thanks.

 

[jbaysurfer]

TAK - it sounds like you and day_trippr use a similar method. I've been using CO2 to siphon from a carboy to keg, and I fill the keg through the beer-out post (so that it fills from the bottom up), but I've never transferred into a sealed keg. Can you explain how you purge the keg and push out the StarSan with CO2? Thanks.

Fill it with Starsan, close it, hook to the Co2, flush it a few times, attach a faucet to the liquid out, use CO2 to push it out. You can also jump it with a jumper (2 Liquid out QDs one on each end of a beer line) to another keg, just loosen the PRV so you can hear the air escaping as the starsan fills the new keg. I do a quick clean of the kegs and then seal them all up and clean the dip tubes this way, then sanitize them all this way, then store them sealed and sanitized for future use.

 

[Woodbrews]

Thanks! I've been flushing my keg with starsan as a separate step. I had not thought to flush it and then fill it without ever opening it. But it makes sense. I'll have to try that on the next batch.
Woodbrews

 

[TAK]

TAK - it sounds like you and day_trippr use a similar method. I've been using CO2 to siphon from a carboy to keg, and I fill the keg through the beer-out post (so that it fills from the bottom up), but I've never transferred into a sealed keg. Can you explain how you purge the keg and push out the StarSan with CO2? Thanks.

Well...

Fill it with Starsan, close it, hook to the Co2, flush it a few times

^ This certainly works, and would be good, but I think a few extra steps is even better. Otherwise, the gas that's left above the StarSan is only ever, at best, a dilute mix of CO2 and air .

Here's what I do:

1- I fill the keg up all the way with StarSan, so it's just overflowing out the top. Then seal the lid on.

2 - I fill up a plastic water bottle with StarSan. I put a carbonator cap on that. Hook up a gas disconnect to the cap, run a short length of tube, ending with a liquid disconnect. Purge the rest of that tube with StarSan.

3 - Hook up the water bottle to the liquid out post on the keg.

4 - Squeeze the bottle and at the same time: pull the pressure release valve until StarSan comes out.

5 - Squeeze the bottle and at the same time: hook up a gas-out disconnect to that post, very briefly, until StarSan comes out.

* At this point, you may think its 100% full. However, the pressure release valve on the lid actually dips down a bit, leaving some space above it. If you shake the keg, you can hear it still sloshes around a bit, which means air. Thus...

6 - Tilt the keg upside down to get that air bubble isolated. Then, slowly tilt back with the gas-out post upward. Stop with the keg tilted at an angle, about 45 degrees. That way that air bubble is sitting right at the gas-out post.

7 - Squeeze the bottle and at the same time: remove the gas-out post from the keg, and pull out the short gas dip tube. At first StarSan foam will flow out, then it will turn to pure liquid. At that time, while still squeezing that bottle, reattach the gas-out post.

* At this point, if you shake the keg, you won't hear a darn thing because it's 100% full.

8 - Push out the StarSan (CO2 in the gas post, StarSan out the liquid post). Personally, I keep all this StarSan in a couple buckets to reuse.

It sounds like a lot, but after doing it a couple times, it's quick and easy. I just did this yesterday to one keg. I know I want to rack a carboy this week. So now I have a sanitized keg sitting in queue, filled with CO2 for whenever I decide to move the beer.

 

[jbaysurfer]

^ I said to flush the keg first before you start pushing starsan out of it. If you properly flush the keg (as anytime you rack to a keg) of the O2, you should have a clean O2 free environment inside the keg right up until you rack.

To reiterate, it's the exact same process of racking beer to the keg, then flushing, then serving (pouring through the dip tube). Only you're using starsan instead. I really don't think you need to jump through hoops to be sure every millimeter of dead space if filled with starsan. Just fill it with CO2 instead.

 

[TAK]

Agreed, I saw you said to flush. I don't think, though, that you'll ever flush out all of the air in that headspace.

It's a game of numbers, and you dilute the amount of air to a fraction by doing it that way, but will not completely get rid of it. And this is absolutely good enough to avoid oxygenation when racking. The problems I've noticed with that are after force-carbing.

The tiny bit of O2 left in there if you flush headspace won't go in when you're just moving beer. But if there's even a fraction of a percent in there, that you then force into solution when force carbing, I think that can make a difference.

Before I implemented the method above, I'd see a noticeable change, particularly in hoppy beers, immediately after carbing. After this extra purging step, that change isn't there.

Plus, flushing use more CO2. If you rely on completely pushing StarSan, then you use only a keg's worth if CO2, nothing more.

 

[orangehero]

It's hard to imagine how co2 purging the tiny headspace of a keg filled with starsan, then pushing the starsan out and filling the whole keg with co2, then transferring beer into the keg which is also releasing co2 from the agitation can leave any significant amount of O2 in the headspace after, and that the effects are noticeable especially if the beer hasn't been filtered and still contains live yeast.

30 psi (2 atmospheres) CO2 dilutes a corny full of air (one atmosphere of air) a dilution of 2:1. So starting with a keg full of air at atmospheric pressure and pressurizing and releasing with 30 psi CO2 reduces the O2 content in the keg like this, assuming good mixing in the keg: First purge cycle: 22% O2 to 7% O2, second purge gives 2.67% O2, third purge leaves 0.9 %, a fourth leaves 0.3 %, a fifth 0.1 %.

 

[dammBrewer]

I just subscribed to this thread. I have recently purchased a conical that can hold up to 5psi for transfers. I do not yet have the equipment (caps and posts and whatever else is required) to do so, but, have been thinking about better transfers. I recently stopped using a secondary (yes, that is another debate in itself) and would like a better way to get beer from fermenter/carboy to keg for carbonation/crashing, etc. I am however having a hard time wrapping my head around how you all do this. Is it possible for someone on here to put a diagram together or several pics of how this works? My visual thinking mind would greatly appreciate it.

Otherwise, great topic and awesome insights.

 

[Woodbrews]

This, from Humbolt Beer Works, is one of the best explanations I've found. An other good explanation can be found here, among back issues of MoreBeer brewing techniques. Finally, another good explanation, with a parts list, can be found here, in back issues of The Beer Journals.

HTH,
Woodbrews

 

[LovesIPA]

The tiny bit of O2 left in there if you flush headspace won't go in when you're just moving beer. But if there's even a fraction of a percent in there, that you then force into solution when force carbing, I think that can make a difference.

For me, that little bit of oxygen in the headspace was enough to noticeably oxidize most beers that I kegged. It took a lot of troubleshooting but I narrowed it down to that one issue.

How I solved it by using two kegs. I purge the keg with CO2 5-6 times and rack the beer from the primary bucket to the keg. I don't purge the autosiphon with CO2 but now that it's mentioned, I will figure out a way to start doing that with my equipment and add it to my process.

Then, I take a separate keg and fill it ALL the way up with water. I use RO water that is treated with UV so it's sterile. I purge O2 out of both tubes and pull the PRV a couple of times to eliminate tiny bit of air trapped under the lid. Then I use CO2 to push all the water out.

Now I have a keg of beer and a keg of CO2. I hook the beer keg up to the gas, and connect the two liquid side posts together. For this you just need two liquid QD's and piece of tubing. Put an extra gas disconnect on the gas side of the CO2 keg so it can vent and then just let it transfer.

This is the only method I've worked out that doesn't give me horrible tasting oxidized beer.

 

[day_trippr]

So ^the two keg thing^ is necessitated by the type of fermenter - the bucket - which I gather can't be rigged to hold enough pressure to push beer directly from it to a keg?

Cheers!

 

[helibrewer]

I just purge the receiving keg with CO2 until a flame cannot burn inside the lip of the keg....that is purged enough for me

 

[LovesIPA]

So ^the two keg thing^ is necessitated by the type of fermenter - the bucket - which I gather can't be rigged to hold enough pressure to push beer directly from it to a keg?

Cheers!

For me, it was just easier to do it this way than it was to modify all my fermenters to accept CO2.

 

[jbaysurfer]

Yeah, if you can't get enough O2 out of a keg by flushing/venting repeatedly with C02, your'e probably getting too many 02 molecules in the keg with your starsan mix too. The water you use to make it has O2 afterall.

Whatever works for you is fine, but I'm super sensitive to oxidation, and unless you're storing a beer for years and years the difference between a solid CO2 flush and a fill every last millimeter with Starsan techinique is never going to be noticeable. Probably ever.

 

[TAK]

Yeah, if you can't get enough O2 out of a keg by flushing/venting repeatedly with C02, your'e probably getting too many 02 molecules in the keg with your starsan mix too. The water you use to make it has O2 afterall.

Whatever works for you is fine, but I'm super sensitive to oxidation, and unless you're storing a beer for years and years the difference between a solid CO2 flush and a fill every last millimeter with Starsan techinique is never going to be noticeable. Probably ever.

The O2 in the StarSan solution doesn't have much opportunity to come out of solution, because it's only in there for 5-10 minutes.

If you're relying on only flushing with CO2, then you're using at least 5-6 times more CO2 to achieve the same result. Example...

Originally Posted by AiredAle
30 psi (2 atmospheres) CO2 dilutes a corny full of air (one atmosphere of air) a dilution of 2:1. So starting with a keg full of air at atmospheric pressure and pressurizing and releasing with 30 psi CO2 reduces the O2 content in the keg like this, assuming good mixing in the keg: First purge cycle: 22% O2 to 7% O2, second purge gives 2.67% O2, third purge leaves 0.9 %, a fourth leaves 0.3 %, a fifth 0.1 %.

The method seemed to make a difference to me, as I said, mostly with hoppy beers. I haven't tried mostly filling and then purging, so I can't compare. But, as Hunter S. Thompson said, "anything worth doing is worth doing right."

I'm not saying there's anything wrong, not at all, with any other method. Just, the couple extra steps to get me as 100% free of O2 as I can imagine while at the same time saving on CO2, is a 2 birds 1 stone kinda thing for me.

Also, the OP was asking about the best method to avoid oxygenation during a transfer. Although what I described is more than what others may do, I don't get the point if arguing against it.

 

[orangehero]

The method seemed to make a difference to me, as I said, mostly with hoppy beers. I haven't tried mostly filling and then purging, so I can't compare."

I read it that you were saying that was the method you were improving upon to avoid the flavor change you were experiencing. So what method were you having issues with? Why not first try mostly filling and then purging instead of going straight to playing around with bottles trying to get every cubic centimeter filled with starsan?

 

[Swiller]

I've recently started to suspect that I'm picking up some oxygen during my transfer from primary to secondary/keg.

To transfer, I get a carboy cap with a stainless steel cane and push in CO2 until the transfer starts. This shouldn't be causing any issues.

The problem comes in with the receiving vessel. When transfering to a carboy, sometimes the bottom of the plastic transfer hose curls up, and I definitely feel like I'm picking up serious oxygen (even if I purge the carboy first).

Any suggestions on how to improve my transfer technique? What do the rest of you do to minimize oxygen pickup?

Ferment under pressure with a keg and sounding valve. I sold 14 glass carboys and never looked back... Since then I upgraded to 10 gallon corny kegs for 5/6 gallon batches (I'd split a batch between two)

I've also used sanke kegs before no got my 10gal corny kegs.

Get a sanke keg and do this:
https://www.homebrewtalk.com/f51/cheap-sanke-keg-fermenter-conversion-kit-completed-447780/ it's worked well for me

But I wanted to get into the keg easier for cleaning while being able to do full volume fermenting, so just recently (finished today) I created my own full 10 gallon capacity fermenter: https://www.homebrewtalk.com/f51/ul...-your-sanke-keg-fermenter-490238/#post6358719

Not only does it eliminate oxygen, but racking to a serving keg is so freaking simple. Try it once, you'll sell all you carboys too.

 

[TAK]

I read it that you were saying that was the method you were improving upon to avoid the flavor change you were experiencing. So what method were you having issues with? Why not first try mostly filling and then purging instead of going straight to playing around with bottles trying to get every cubic centimeter filled with starsan?

Like I said, to me, anything worth doing is worth doing right. I'm not trying to improve, per se, upon the method of mostly filling, flushing, then pushing. It's just that the first time I setup to push StarSan instead of flushing, I realized there was still O2 in there. A couple more minutes of fiddling, then there was none. Prior to that, I was just flushing.

 

[jbaysurfer]

Even if you factor in reuse, C02 cost less then starsan.

 

[LovesIPA]

Whatever works for you is fine, but I'm super sensitive to oxidation, and unless you're storing a beer for years and years the difference between a solid CO2 flush and a fill every last millimeter with Starsan techinique is never going to be noticeable. Probably ever.

Define "solid CO2 flush"?

 

[jbaysurfer]

Define "solid CO2 flush"?

Unless we've got 02 meters to compare, it's a pointless endeavor. Every person that's ever kegged has to figure out what that means. I've read people that say 3 times is all you need, and Denny Conn does it 10 times. I probably lean more toward the latter.

 

[LovesIPA]

In my experience, it didn't matter how many times I vented it. I still ended up with oxidized beer. Apparently it takes VERY little O2 in the headspace to oxidize a beer in 2-3 days.

 

[duffy5018]

So, theoretically, if you do a CO2 flush on an upside down keg, and use a hose on the out port to vent it instead of the PRV, the CO2 should stay low, the O2 should rise to the dip tube, and then you can flush once, completely clear headspace of O2, and not use as much StarSan.

Unless I'm missing something here...

 

[jbaysurfer]

In my experience, it didn't matter how many times I vented it. I still ended up with oxidized beer. Apparently it takes VERY little O2 in the headspace to oxidize a beer in 2-3 days.

I don't know what to tell you then. Flushing much larger tanks with CO2 is how commercial breweries all over the country do it. Seems to work for them.

 

[jbaysurfer]

So, theoretically, if you do a CO2 flush on an upside down keg, and use a hose on the out port to vent it instead of the PRV, the CO2 should stay low, the O2 should rise to the dip tube, and then you can flush once, completely clear headspace of O2, and not use as much StarSan.

Unless I'm missing something here...

I just learned this recently, but the ideal gas law says that this won't quite get it done. while the tank is upside down some of the O2 molecules will mix in with the CO2. You'll have to do it a couple times to get O2 levels down to the point where another flush is diminishing returns. It's important to note that there is no technique outside of a laboratory that will get every last molecule of CO2 out of your tank, nor your beer.

 

[LovesIPA]

So, theoretically, if you do a CO2 flush on an upside down keg, and use a hose on the out port to vent it instead of the PRV, the CO2 should stay low, the O2 should rise to the dip tube, and then you can flush once, completely clear headspace of O2, and not use as much StarSan.

Unless I'm missing something here...

Gasses don't stratify like liquids can. It doesn't matter how long you let a tank of CO2 and air sit, the gasses inside will never stratify.

 

[TAK]

So, theoretically, if you do a CO2 flush on an upside down keg, and use a hose on the out port to vent it instead of the PRV, the CO2 should stay low, the O2 should rise to the dip tube, and then you can flush once, completely clear headspace of O2, and not use as much StarSan.

Unless I'm missing something here...

Gas will always mix. The CO2 doesn't push out the air. They mix together, diluting the O2. Doing it this way, you'd still need to purge, dilute further, purge again, and repeat.

 

[TAK]

Even if you factor in reuse, C02 cost less then starsan.

I'm not sure about this. A bottle of StarSan cost me $11. I've been brewing 2 years, and I just bought my second bottle.

Refills on my 5lb CO2 tank cost, can't recall exactly, but about $20 +/-. I was going threw my 5lb tank every 6-8 weeks or so, until this last time I upgraded to a 20lb tank.

 

[jbaysurfer]

I'm not sure about this. A bottle of StarSan cost me $11. I've been brewing 2 years, and I just bought my second bottle.

Refills on my 5lb CO2 tank cost, can't recall exactly, but about $20 +/-. I was going threw my 5lb tank every 6-8 weeks or so, until this last time I upgraded to a 20lb tank.

Are you testing the PH on your starsan, mine doesn't last that long on reuse. I think I'm right..you question that..no point in debate I figure.

 

[TAK]

Are you testing the PH on your starsan, mine doesn't last that long on reuse. I think I'm right..you question that..no point in debate I figure.

I do test occasionally, but agreed, no point in debating this.

 

[Woodbrews]

In my experience, it didn't matter how many times I vented it. I still ended up with oxidized beer. Apparently it takes VERY little O2 in the headspace to oxidize a beer in 2-3 days.

I'm not challenging this point, just trying to understand it. How will I know that my beer's been oxidized? I can't say I've ever detected the so-called cardboard taste. My racking practices are certainly not as thorough or sophisticated as those discussed here (although they're getting better thanks to this thread). Maybe I'm just drinking my beer too fast to notice!:rockin:

 

[BreezyBrew]

I'm not challenging this point, just trying to understand it. How will I know that my beer's been oxidized? I can't say I've ever detected the so-called cardboard taste. My racking practices are certainly not as thorough or sophisticated as those discussed here (although they're getting better thanks to this thread). Maybe I'm just drinking my beer too fast to notice!:rockin:

I have had most of a batch splash while I was transferring one time when the starsan foam was so thick I couldn't see the bottom. I was using vinyl tubing back then and it wasn't being very forgiving. Even that batch was hard to pick out the oxidation and it didn't seem to show up until week 3 or 4. Now, I certainly can if I'm looking for it, but it's not all that noticeable to someone who isn't studying the beer.

I've also had a very faint rotten fruit aroma before on a previous batch. I have read Fix say that can be oxygenation. That was some of my main interested in this thread.

 

[LovesIPA]

I'm not challenging this point, just trying to understand it. How will I know that my beer's been oxidized? I can't say I've ever detected the so-called cardboard taste. My racking practices are certainly not as thorough or sophisticated as those discussed here (although they're getting better thanks to this thread). Maybe I'm just drinking my beer too fast to notice!:rockin:

In my case, oxidation flavors showed up within 48 hours. If I am not extremely careful with racking and purging, the tiny bit of oxygen left in the headspace is enough to noticeably oxidize the beer.

I've also picked up the flavor in a couple of commercial beers too. I bought a sixer of Deschutes Fresh-squeezed IPA and all of them were oxidized pretty bad.

The flavor is really hard to describe for me. I wouldn't pick wet cardboard, but I have always been at a loss for adjectives for it.