Same. If you don't, you just end up with a hop sludge floating on the surface. I give mine a good swirl at least twice a day while dry hopping. I've often wondered if you could do some sort of large stir plate with a fermenter. Nothing crazy, just enough to get the hops moving around.
Pressurized Closed Loop Corny Keg Fermenting
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Same. If you don't, you just end up with a hop sludge floating on the surface. I give mine a good swirl at least twice a day while dry hopping. I've often wondered if you could do some sort of large stir plate with a fermenter. Nothing crazy, just enough to get the hops moving around.
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Maybe. If you are dry hopping while spunding there is going to be a lot less agitation than doing it at high krausen.
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I swirled aggressively once and dislodged the floating dip tube. Pumps and stir bars are definitely on my radar. schematix, what tubing are you thinking for the peristaltic pump? You would want it to be less permeable than silicone and able to handle higher pressure.
Probably something like a thick walled or double walled pvc (beer line?). Definitely not silicone due to permeability.
Also one of the reasons i'm thinking to only recirc for a few hours is to limit exposure time. Obviously great care would need to be taken to purge the recirculation loop, hops, etc. I still think spunding is part of the solution too.
Also one of the reasons i'm thinking to only recirc for a few hours is to limit exposure time. Obviously great care would need to be taken to purge the recirculation loop, hops, etc. I still think spunding is part of the solution too.
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The pump works by positive displacement i.e. squeezing the tubing. So it needs to be very flexible.
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Transferring takes what, 30 mins? Is that enough time to extract from the hops?
Yah i had the same realization on my drive home last night.... thick walled beer line definitely not the way to go.
Not a lot of time to dedicate currently but some other ideas could be a diaphram pump, or just use silicone (?) tubing and limit exposure time.
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stickyfinger
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I'm sure McMaster Carr or Cole Parmer have the perfect tubing for the job, some soft, food grade peristaltic pump tubing that maybe would be decent at keeping out oxygen. Though, for the short contact time, I don't know how bad the oxygen exposure would really be. I mean, is oxygen really going to get through the tubing in a day, maybe. Anyway, where there is a wallet, there is a way.
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This stuff is low my priorities too but I want to revisit at some point and get it nailed down.
stickyfinger
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My first spunding setup was just delivered today, woo hoo. I have a couple questions about the process:
- once i remove the blowoff setup from the FV and reattach the gas out post and poppet, should i pressurize the FV with my CO2 cylinder to like 5 PSI and attach the spunding valve to it to ensure the oxygen that was introduced when i took off the blowoff setup is removed (before connecting the jumper to the SV?)
- how long should i wait to attach the SV to the FV and move the spunding valve over to the SV so that pure CO2 can purge the SV?
- when doing a dry hop, i would take off the jumper, add the dry hops to the FV, seal up the FV and then purge the head space with my CO2 cylinder a few times? Would I then move the spunding valve back over to the FV from the SV so that the oxygen introduced during dry hopping can escape or be consumed by yeast? How long do I have to wait for the oxygen to be consumed? Should I set the spunding valve to 20 PSI at that point or keep it low ( I assumed why not set it high at that point.)
- Once I am confident the oxygen introduced into the FV during dry hopping is purged or consumed, I assume I can then reattach the jumper (after purging it by using the pressure in the SV) b/w the FV and SK and let the pressures equilibrate. The 4-5 points of gravity is enough to both carbonate the beer and pressurize the SV to 20 PSI?
- once i remove the blowoff setup from the FV and reattach the gas out post and poppet, should i pressurize the FV with my CO2 cylinder to like 5 PSI and attach the spunding valve to it to ensure the oxygen that was introduced when i took off the blowoff setup is removed (before connecting the jumper to the SV?)
- how long should i wait to attach the SV to the FV and move the spunding valve over to the SV so that pure CO2 can purge the SV?
- when doing a dry hop, i would take off the jumper, add the dry hops to the FV, seal up the FV and then purge the head space with my CO2 cylinder a few times? Would I then move the spunding valve back over to the FV from the SV so that the oxygen introduced during dry hopping can escape or be consumed by yeast? How long do I have to wait for the oxygen to be consumed? Should I set the spunding valve to 20 PSI at that point or keep it low ( I assumed why not set it high at that point.)
- Once I am confident the oxygen introduced into the FV during dry hopping is purged or consumed, I assume I can then reattach the jumper (after purging it by using the pressure in the SV) b/w the FV and SK and let the pressures equilibrate. The 4-5 points of gravity is enough to both carbonate the beer and pressurize the SV to 20 PSI?
One question about purging with fermentation C02 - should I see the jar of sanitizer bubble up, like a normal airlock would? This is connected to the serving keg via a quick disconnect attached to the gas out post.
stickyfinger
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i would think you have to use a spunding valve or there wont be enough pressure to seal the keg lids, but i might be wrong.
It seals well enough and once fermentation begins it’s no problems what so ever.
stickyfinger
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wow! really?! I had assumed you needed a little back pressure from the spunding valve to seal the kegs. I wonder what the pressure is in the kegs when the fermentation is going strong? I guess it depends on the diameter of the tubing you are using?
I HAVE noticed that my brand new kegs with good o-rings and no dents do hold pressure at pretty low PSI. I guess if this is true then you could probably do all of this without a spunding setup if you needed to. Also, if you filled up a large column of water or starsan for the output, you could increase the pressure in the kegs.
Not sure what the internal pressure is off the top of my head. Maybe i’ll math it out in the morning. Suffice to say it’s more than enough for a good seal and enough to prevent oxygen ingress.
Damn straight. I ordered some "lightly used" kegs from one of the most common keg suppliers for homebrewers and they looked like they were run over by tanks. From now on, I just buy new AEB kegs. Awesome build quality and I don't have to worry about mixing up lids, posts and poppets.
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I see bubbles like you do in an airlock.
1 psi is equivalent to 27.7 inches of water.
stickyfinger
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That's why I usually fill up a bucket with mercury. ha ha ha
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That would work. What could possibly go wrong.
Hmmm. Cause I'm not seeing them. This is my first time using an SS conical, so it should be more airtight than my previous big mouth bubbler.
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Check the connections and figure out where that C02 is going because it's got to be going somewhere. Could be a loose lid.
Or maybe the fermentation is lagging or stalled.
Or maybe the fermentation is lagging or stalled.
Turns out it was a loose hose barb...had the wrong size for the tube I was using. Doh! Fixed that, and it started bubbling right away. Awesome! Thanks
Can some one explain the need for the priming sugar during transfer?
If the "dilution game" holds true for o2 then the reverse is also true and there should be little to no o2 remaining in the serving keg with the water purge and all the co2 from fermentation if you're spunding through it.
Then if that's true, should you be able to ramp the pressure up at the end of fermentation and carb from that alone?
If the "dilution game" holds true for o2 then the reverse is also true and there should be little to no o2 remaining in the serving keg with the water purge and all the co2 from fermentation if you're spunding through it.
Then if that's true, should you be able to ramp the pressure up at the end of fermentation and carb from that alone?
stickyfinger
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I think there are at least 3 reasons for using priming sugar:
a) too lazy to do a forced ferment test and then pressurize right around 4-5 pts left (could just up the pressure anytime, but not everyone wants to ferment under higher pressure I presume)
b) you miss the time period to ramp up pressure due to the beer dropping really fast or whatever else goes on in life so you need more food for more CO2 (as appears to have happened on my first attempt at spunding a saison!)
c) you want to add dry hops at the same time as ramping up the pressure and don't really want any of the gas to escape so it needs to be pretty close to the right amount of CO2 production left to carbonate the keg
a) too lazy to do a forced ferment test and then pressurize right around 4-5 pts left (could just up the pressure anytime, but not everyone wants to ferment under higher pressure I presume)
b) you miss the time period to ramp up pressure due to the beer dropping really fast or whatever else goes on in life so you need more food for more CO2 (as appears to have happened on my first attempt at spunding a saison!)
c) you want to add dry hops at the same time as ramping up the pressure and don't really want any of the gas to escape so it needs to be pretty close to the right amount of CO2 production left to carbonate the keg
stickyfinger
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OK, so I just tried my first closed fermentation. It has gone off pretty well so far! I filled a keg pretty full with saison wort with the yeast added as it was filling, oxygenated, sealed it up and put on a blowoff. At 24 hrs or so from pitch it was thumping away and no blowoff, so I attached a sanitized keg (not purged, as I didn't have enough gas left in my cylinder (great timing) and set it to spund at around 4 PSI. I came back around 12 hrs later and it was at around 4 PSI slowly hissing from the valve, awesome.
I came back about 12 hrs later again and the pressure has already dropped to maybe 3 PSI and there is not leaking gas, so I took off the valve. I guess it is done fermenting!? I didn't realize my fermentations were happening so fast!
So, I only got maybe 24 hrs of purging of my serving keg, and now I don't have any fermentables left to carbonate. So, my plan is to hope I got enough purging of my serving keg, add priming sugar to through the keg PRV, purge headspace, let rest for a few hours, then hook up to the serving keg and let it transfer over, hopefully with a few points of sugar left to scrub some O2 from the serving keg.
I came back about 12 hrs later again and the pressure has already dropped to maybe 3 PSI and there is not leaking gas, so I took off the valve. I guess it is done fermenting!? I didn't realize my fermentations were happening so fast!
So, I only got maybe 24 hrs of purging of my serving keg, and now I don't have any fermentables left to carbonate. So, my plan is to hope I got enough purging of my serving keg, add priming sugar to through the keg PRV, purge headspace, let rest for a few hours, then hook up to the serving keg and let it transfer over, hopefully with a few points of sugar left to scrub some O2 from the serving keg.
Ok. If I dry hop it's usually a biotransform happening on day one leaving ample time for fermentation to remove o2. I've yet to try of dry hopping right at yeast pitch but this certainly would merit it.
What's the best way to add the priming sugar? Seems like a royal PITA. I imagine you could push it with another keg? Anyone out there doing this with great success without priming sugar?
stickyfinger
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schematix recommended a very low pressure purge of the headspace with a co2 cylinder while using a 100 mL syringe to inject the soln through the PRV. I plan to try it soon.
The PRV on the spunding valve? Or the PRV on the top of the keg. Most of my kegs dont have the latter.
stickyfinger
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the keg PRV. maybe you could crack the lid and inject it while purging?
Yeah. Or I was thinking a valve with a nipple on a disconnect through the gas post may work.
Its preferred to inject the priming solution into the fermenter first, but if you're already in the serving keg this is what you can do:
1. Make your priming solution. Boil for at least 5 minutes. Use a little more water than you normally would to accoutn for boil off.
2. Put in ice bath (we want to perform this procedure as quickly as possible so the priming solution doeesn't pick up O2 from the air.)
3. Apply bottle CO2 pressure to keg via gas post. Maybe 3-5 psi... enough to get flow.
4. Relieve pressure and unscrew PRV. You should immediately feel gas coming out - if not, crank up pressure.
5. Draw in required amount of priming solution into large 100mL syringe.
6. Insert syringe into PRV hole. NOTE: be sure you have hold of the plunger so it doesn't rocket backwards towards you.
7. Force priming solution in.
8. Reinstall PRV.
9. Allow keg to minimally pressurize so the lid seats.
Then monitor the pressure.
I don't install my spund valve at all unless i hit target pressure because it has a very slow leak, which prevents carbonation over many days. I normally only attach it for a few hours, or at most overnight, at a time so i don't lose all my pressure when fermentation winds down.
1. Make your priming solution. Boil for at least 5 minutes. Use a little more water than you normally would to accoutn for boil off.
2. Put in ice bath (we want to perform this procedure as quickly as possible so the priming solution doeesn't pick up O2 from the air.)
3. Apply bottle CO2 pressure to keg via gas post. Maybe 3-5 psi... enough to get flow.
4. Relieve pressure and unscrew PRV. You should immediately feel gas coming out - if not, crank up pressure.
5. Draw in required amount of priming solution into large 100mL syringe.
6. Insert syringe into PRV hole. NOTE: be sure you have hold of the plunger so it doesn't rocket backwards towards you.
7. Force priming solution in.
8. Reinstall PRV.
9. Allow keg to minimally pressurize so the lid seats.
Then monitor the pressure.
I don't install my spund valve at all unless i hit target pressure because it has a very slow leak, which prevents carbonation over many days. I normally only attach it for a few hours, or at most overnight, at a time so i don't lose all my pressure when fermentation winds down.
stickyfinger
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is the 75g of priming sucrose enough to pressurize the serving keg and carbonate the beer to 2 vols or so? I was planning on injecting the priming solution to primary with purging, let rest a few hours or so to scrub some O2 and get yeast activity to build a little pressure in both kegs and then transfer to the serving keg. (my serving keg is only at maybe 3 PSI after primary fermentation.)
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there are calculators out there that'll tell you... you're in the ball park, but it all depends upon the remaining sugar and the current/max temperature the batch has been exposed to.
Can you comment if a guy can get away without the priming sugar racket?
