Pressurized Closed Loop Corny Keg Fermenting

[enormous13]

Pressurized Closed Loop Corny Keg Fermenting
https://www.homebrewtalk.com/forum/index.php?posts/8278917/

The post above.

Wow, that's ingenious...Could you do hop extract in the same way? To get around opening the keg for dry hopping...

 

[Hannabrew]

Wow, that's ingenious...Could you do hop extract in the same way? To get around opening the keg for dry hopping...

I have yet to use hop extract but I would worry about it being too sticky to pass through everything.

the syringe method may work better for hops extract as there is less to go through, you can make sure it's all pushed through, and it's easier to clean if it is sticky

 

[ba-brewer]

I thought hop extracts were for adding bitterness and not really for flavor or aroma.

 

[schematix]

I thought hop extracts were for adding bitterness and not really for flavor or aroma.

There are different types. Up until recently only non-isomerized (you have to boil them) oils were widely available.

 

[crane]

Do you remember the post? I'd like to see those numbers. The pressure up and release is very ineffective but that's not the method I'm talking about here, which is hooking the gas up and having it flow out an open picnic tap via the beverage post dip tube at atmospheric pressure. In a perfect world, all you'd need is one keg volume of CO2 displaced through but obviously there is no way to ensure that all the CO2 you're putting in is 100% displacing O2, there is a lot of mixing happening.

This isn't the original post on the topic, but has the same data.

https://www.homebrewtalk.com/forum/index.php?posts/8351644

 

[stickyfinger]

For example:

https://www.morebeer.com/products/distilled-hop-oil-chinook-1-ml.html

Do they have oils that are from dried hops though? I think most of them are from wet hops aren't they? That would be very different in character.

There are different types. Up until recently only non-isomerized (you have to boil them) oils were widely available.

 

[Andre3000]

This isn't the original post on the topic, but has the same data.

https://www.homebrewtalk.com/forum/index.php?posts/8351644

See, that is a "pressure and release" purge and I believe those numbers are sound for that method. But like I said what I do is different: hook the CO2 cylinder up to the gas post and a picnic tap up to the bevage post. Once I drain the remaining starsan, I allow the CO2 to run through the keg for a bit.

 

[schematix]

For example:

https://www.morebeer.com/products/distilled-hop-oil-chinook-1-ml.html

Do they have oils that are from dried hops though? I think most of them are from wet hops aren't they? That would be very different in character.

I just got some of that stuff a couple weeks ago and am planning to use it soon. Going to make my IPA the same as always, except halve the dry hops (down to about 6oz from 12oz) and split the 1mL between 2 kegs. Will probably add it to some vodka first so i can get a more accurate dosing.

I've never made a 'wet hop' beer before so i'm not really sure what to expect.

AFAIK there are hop oils made from steam distillation of pellet hops, as well as supercritical CO2 extraction. I believe the CO2 stuff is what you normally see as like a HopShot and is used for bittering. It must be boiled.

 

[stickyfinger]

I just got some of that stuff a couple weeks ago and am planning to use it soon. Going to make my IPA the same as always, except halve the dry hops (down to about 6oz from 12oz) and split the 1mL between 2 kegs. Will probably add it to some vodka first so i can get a more accurate dosing.

I've never made a 'wet hop' beer before so i'm not really sure what to expect.

AFAIK there are hop oils made from steam distillation of pellet hops, as well as supercritical CO2 extraction. I believe the CO2 stuff is what you normally see as like a HopShot and is used for bittering. It must be boiled.

interested to see how it tastes

 

[stickyfinger]

Have you used the Hornindal from Omega? I thought it had very nice flavor. It seemed to really attenuate more than I expected though. Have you seen higher than usual attenuation using the kveik strains?

I don't see any reason to rest it at 70. I have pushed all the Omega Kveik strains into the 90's and have been pleased with the results. What did your fermentation schedule look like? I like to give it a few days to clean up after reaching FG. Either that or do a forced diacetyl test to be sure any precursors are gone.

It sounds like you're pulling from the bottom. If you pick up a floating dip tube, you can pressure transfer to a keg with the floating dip tube installed, crash then use that for your SV.

I have not experienced any issues with pressure fermenting the Kveik strains. I have Hothead and Escarpment Labs Hornindal on tap now. They actually got away from me during fermentation, maxed my 60 psi gauges and they're both drinking great (had to bleed them of course).

I feel like Voss has the most farmhouse character of the 3. You'll get a lot of citrus and even a bit of tartness so just a heads up; your final product will probably resemble a saison more than a blonde.

 

[TimmyWit]

Have you used the Hornindal from Omega? I thought it had very nice flavor. It seemed to really attenuate more than I expected though. Have you seen higher than usual attenuation using the kveik strains?

As far as attenuation; maybe a bit but nothing too crazy that I recall. I have used Hornindal from Omega and it is very nice. The only one from Omega I haven't tried yet is Jovaru but it is waiting for me in the fridge for my next brew day.

 

[Andre3000]

I discovered another nifty technique that I've been playing around with, maybe others do this as well but I'll mention it anyway. This may be appealing to you CO2 purists. If you're fully spunding to carb, disregard this post.

I will mention that I cold crash before transfer which seems to be working extremely well with the floating dip tube especially if you transfer under a higher pressure than spund to keep foaming down. I have also gone away from high spunding pressures because of trapping undesirable compounds / dry hopping issues. YMMV on that topic.

So instead of hooking gas-gas and liquid-liquid and starting a siphon, I hook the gas post up on the fermenter to my CO2 cylinder and liquid-liquid up (obviously) and pressure transfer. This way I do not have to move the fermenter after it's been cold crashed. I then open the gas on the cylinder and slowly increase the pressure until the transfer starts. Depending on headspace and spund pressure, you can usually transfer off the entire thing and end up with compressing all that pure CO2 in the serving keg with the beer and either shake to carb or just let it sit. If the pressure gets too high in the serving keg while you're transferring you shake it a bit to absorb the CO2 and continue the transfer. The beer won't be fully carbed using this method but it gets it quite close depending on spunding pressure.

In most instances, this method works so well there is literally nothing left except a dry yeast cake.

 

[leesmith]

I discovered another nifty technique that I've been playing around with, maybe others do this as well but I'll mention it anyway. This may be appealing to you CO2 purists. If you're fully spunding to carb, disregard this post.

I will mention that I cold crash before transfer which seems to be working extremely well with the floating dip tube especially if you transfer under a higher pressure than spund to keep foaming down. I have also gone away from high spunding pressures because of trapping undesirable compounds / dry hopping issues. YMMV on that topic.

So instead of hooking gas-gas and liquid-liquid and starting a siphon, I hook the gas post up on the fermenter to my CO2 cylinder and liquid-liquid up (obviously) and pressure transfer. This way I do not have to move the fermenter after it's been cold crashed. I then open the gas on the cylinder and slowly increase the pressure until the transfer starts. Depending on headspace and spund pressure, you can usually transfer off the entire thing and end up with compressing all that pure CO2 in the serving keg with the beer and either shake to carb or just let it sit. If the pressure gets too high in the serving keg while you're transferring you shake it a bit to absorb the CO2 and continue the transfer. The beer won't be fully carbed using this method but it gets it quite close depending on spunding pressure.

In most instances, this method works so well there is literally nothing left except a dry yeast cake.

Could you share some pictures to help with the description?

 

[Andre3000]

Could you share some pictures to help with the description?

Sorry this took so long.

Keep in mind this is just for transferring. I use the same blow through serving keg with spunding value during fermentation. I believe this method of transferring has the following benefits:

-Allows you to cold crash and transfer without moving the fermenter at all. Especially useful with a floating dip tube since the yeast/trub will be nicely compacted and undisturbed.
-Faster transfer than the double connection siphon (though that is still a great method).
-Uses up all that valuable pure CO2 that was created during fermentation.

You effectively don't need the spunding valve on the serving keg while your transfer either as the balance of the cylinder regulator with the compressed CO2 headspace dictates the system pressure.

 

[leesmith]

Sorry this took so long.
View attachment 596899

Keep in mind this is just for transferring. I use the same blow through serving keg with spunding value during fermentation. I believe this method of transferring has the following benefits:

-Allows you to cold crash and transfer without moving the fermenter at all. Especially useful with a floating dip tube since the yeast/trub will be nicely compacted and undisturbed.
-Faster transfer than the double connection siphon (though that is still a great method).
-Uses up all that valuable pure CO2 that was created during fermentation.

You effectively don't need the spunding valve on the serving keg while your transfer either as the balance of the cylinder regulator with the compressed CO2 headspace dictates the system pressure.

No worries....thanks for posting.
When you cold crash do you hook gas up to the FV to deal with suck back?

 

[Andre3000]

No worries....thanks for posting.
When you cold crash do you hook gas up to the FV to deal with suck back?

Hooking up the gas isn't necessary. As long as you've spunded above atmospheric at 5 psi or so, "suckback" will just result in a small pressure drop of the system due to the cooling and contraction of the headspace CO2. Out of curiosity, I did a quick calc assuming 25% headspace in the fermentation keg, cold crashed from 68-37°F, and it resulted in less than a .1 psi pressure drop in the system.

Edit: Thanks to member Crane for highlighting a caveat/error with this post. I don't cold crash for very long, 24-48 hours. You will definitely experience suckback if you allow the beer to fully dissolve the CO2 at its new cold crashed temperature. See his post below.

 

[FunkedOut]

I posted this in another thread, thinking that thread was this one.
Anyway, here’s the repost:

Got a plan for dry hopping in the fermentation keg. Put it into play yesterday.

Sanitized a hop sock and some thin nylon thread in a jar of starsan.
Filled sock with dry hop charge (and a stainless bar for weight) and tied it off with the thread.

After pitching yeast into keg, I seal it up and pressurize with pure O2, shake it up for a while then vent.

Now I removed the safety valve, removed the lid and fed the thread through the safety valve opening, then reinstalled the safety valve.

I only let the bag down far enough to hang in the air above the beer.
Once fermentation is done, I will quickly pull the safety valve ring, allowing the hop sock to fall to the bottom.
It worked perfectly during the dry runs.

The thread is thin enough that the valve still holds pressure just fine.
Just have to remember to sanitize the thread again (or cut it) before pulling the ring.

 

[afro_lou]

Hooking up the gas isn't necessary. As long as you've spunded above atmospheric at 5 psi or so, "suckback" will just result in a small pressure drop of the system due to the cooling and contraction of the headspace CO2. Out of curiosity, I did a quick calc assuming 25% headspace in the fermentation keg, cold crashed from 68-37°F, and it resulted in less than a .1 psi pressure drop in the system.

Thanks for posting this! I was just about to ask what the general pressure drop during cold crashing would be.

Does anyone see any issue with spunding to 8psi during the cold crash and carbonating in the fermentation vessel before (close-system) transferring to a serving keg?

 

[crane]

Hooking up the gas isn't necessary. As long as you've spunded above atmospheric at 5 psi or so, "suckback" will just result in a small pressure drop of the system due to the cooling and contraction of the headspace CO2. Out of curiosity, I did a quick calc assuming 25% headspace in the fermentation keg, cold crashed from 68-37°F, and it resulted in less than a .1 psi pressure drop in the system.

Not sure how you did your math, but all the carbonation charts posted all over the internet tend to disagree with your conclusion. In my experience, if I finish fermentation in the upper 60s and at 20-25 psi I will have somewhere between 2.2 and 2.4 volumes of CO2. After cold crashing the pressure drops down to 8-10 psi and maintains the same carbonation level.

If I plug 1.35 volumes of CO2 and 65f into beersmiths carbonation calculator I get 8.38psi. When I keep the volumes of CO2 the same and drop the temperature to 40f, the resulting pressure is 0 psi. If you start with 1.5 volumes of CO2, you will still have 1.37psi after cold crashing. 1.5 volumes of CO2 would require 10.68psi at 65f. So if you start with 8psi before cold crashing you may still experience suck back, but if you start at 10psi you will still have positive pressure after cold crashing which will prevent suck back from happening.

 

[Andre3000]

Not sure how you did your math, but all the carbonation charts posted all over the internet tend to disagree with your conclusion. In my experience, if I finish fermentation in the upper 60s and at 20-25 psi I will have somewhere between 2.2 and 2.4 volumes of CO2. After cold crashing the pressure drops down to 8-10 psi and maintains the same carbonation level.

If I plug 1.35 volumes of CO2 and 65f into beersmiths carbonation calculator I get 8.38psi. When I keep the volumes of CO2 the same and drop the temperature to 40f, the resulting pressure is 0 psi. If you start with 1.5 volumes of CO2, you will still have 1.37psi after cold crashing. 1.5 volumes of CO2 would require 10.68psi at 65f. So if you start with 8psi before cold crashing you may still experience suck back, but if you start at 10psi you will still have positive pressure after cold crashing which will prevent suck back from happening.

Thank you good sir. You've highlighted a bit of a caveat I should have mentioned and you raise a a very valid point. I did not consider CO2 solubility at all! But I am not cold crashing for a long period of time before I transfer; 24-48 hours. I have never really noticed a pressure drop in that amount of time.

You've got me wondering, how long will it take for it to actually hit 0 psi under my initial assumptions. I think I'll test that.

Thanks for posting this! I was just about to ask what the general pressure drop during cold crashing would be.

Does anyone see any issue with spunding to 8psi during the cold crash and carbonating in the fermentation vessel before (close-system) transferring to a serving keg?

See Crane's post above, as what I initially told you may not be correct in your application. I think the answer you were looking for is what he posted.

 

[afro_lou]

Thanks for the updates! And actually, the above does bear out! I just cold crashed a beer at 8psi at 70°F(11 gallons in a 1/2bbl sanke fermenter), and once it hit 32° the spunding read 0psi. I spent a good amount of time before using the sanke testing how well it held pressure, and it is solid up to 20psi or so, so I don’t think it was leaks or anything.

Next time I’ll try 10psi and see what happens.


Thanks!

 

[4of7]

I set the gas out as a blow off first then switch to the spunding 20psi... other pic of the transfer

 

[Andre3000]

I set the gas out as a blow off first then switch to the spunding 20psi... other pic of the transfer

That's an awesome fermenter! How did you attach the triclamp to the keg?

 

[gnor]

It looks like this one, https://www.morebeer.com/products/kegmenter-fermentation-keg-132-gal.html

 

[4of7]

I bought it way...I like that it has 4inch tri clamp..it it easy for me to get my hand in

 

[4of7]

It looks like this one, https://www.morebeer.com/products/kegmenter-fermentation-keg-132-gal.html

Yes that is the one.. works great for me.. like that I can harvest yeast.saving . money

 

[Adam Zerwick]

After studying this awesome thread for a while I finally got around to trying it out and effed up a little... I was hoping to get your advice on whether or not I should use the serving keg with the second dry hop addition. When I jumped the FV to the SV there was so much activity (or I did something wrong) that a bunch of beer transferred over to the SV. So right now I've got a majority of the beer still in the FV with a small amount of beer/yeast and DDH in the SV. My feeling is that is should be fine to transfer over to the SV. Any help would be greatly appreciated!!

I ferment in corny kegs - always do split batches of 7gal - 3.5gal into each keg.
Day 0 - fermenting keg, water purged and wort added.
Day 0 - serving keg, water purged then dryhop added (keg hops) - hold for now
12-24hrs - gas "in" from fermenting keg to "out" of serving keg with dryhops. "In" of serving keg to sanitzer so that ferment gas flows thru bith an escapes. This CO2 purging continued until about 60-72hrs post pitch.
60-72hrs - biotrans dryhop added to fermenting keg. Gas out removed from serving keg to allow pressure to build in both fermenting & serving kegs. Spund to 22lbs. Separate & seal serving keg.
Day 10 cold crash fermenting keg for two days.
Day 12 transfer to serving keg for the final dryhop (serving keg still pressurized) beer naturally carbed from spund.
Day 14 chill, gas and serve

 

[leesmith]

After studying this awesome thread for a while I finally got around to trying it out and effed up a little... I was hoping to get your advice on whether or not I should use the serving keg with the second dry hop addition. When I jumped the FV to the SV there was so much activity (or I did something wrong) that a bunch of beer transferred over to the SV. So right now I've got a majority of the beer still in the FV with a small amount of beer/yeast and DDH in the SV. My feeling is that is should be fine to transfer over to the SV. Any help would be greatly appreciated!!

Use it.
It should be fine as long as you’ve kept it low o2....purged and then purged through fermentation.

I’d be interested to see if this technique works with the hops in the serving keg....any loss of aroma/flavor due to extended time with blow off attached and at fermentation temp. Compared to other dry hopping methods of course.

 

[Siouxerbrewer]

Yes that is the one.. works great for me.. like that I can harvest yeast.saving . money

Do you mind sharing your yeast harvesting technique with the kegmenter please? Cool setup!

 

[4of7]

Do you mind sharing your yeast harvesting technique with the kegmenter please? Cool setup!

First. No disrespect to the thread starter.. My learning curve was more of a Beer shower.. thanks.now you can roast me.. okay I choose this set up for a reason. But first I need explain the process.I am not a"Beer Troll" kegmenter is the primary , I ferment for two weeks or more under pressure mostly 20 PSI on spunding.. Transfer day. prep receiving keg or kegs . you know starsan. The primary keg is still under 20 PSI. I will put a pinic tap on the gas and pull a taste.it will pull from the bottom some yeast and trub and beer..if all is good..look at my thread,as I do not take readings NEVER...if it's still good .... I will pull the prv to release or Purge all the pressure.then I will put gas on at 5psi from the co2.. the receiving keg I will Purge fill it and Purge..the liquid out side of the primary to the liquid out side of the receiving keg .pull up the prv on the receiving keg .. Hook up primary liquid first the receiving keg..... Transfer the beer it will have some trub and yeast in the line at first but it will run clear. This the reason I got this keg . because it has ball locks...wh wh you see the transfer line change ... what happens I think is the area around the dip tube collapse the cone.... yes what you have in the line is some trub and yeast..... take off the liquid lines and put the picnic tap on.. I will have a half gallon Mason jar to use.. of course it's starsan ..

...b pale took off into the first phase with in 45 minutes of pitching.