Author Topic: Keg dry hoping + keg purge, how to do that?  (Read 1120 times)

Offline Philbrew

  • Brewmaster
  • *****
  • Posts: 866
    • View Profile
Keg dry hoping + keg purge, how to do that?
« on: June 26, 2017, 01:07:28 AM »
Lately it's become good practice to CO2 purge your kegs before filling to help prevent beer staling.  That's easy to do with a little set up to completely fill kegs with Star-San and then blow the Star-San out with CO2. 

The question is how do you then get a mesh bag of hops (pellet or whole) into the keg without screwing up the nice purge? 
Or do you put the hops in before the purge and the Star-San doesn't screw up the hops? 
Or do you say "screw the purge, this beer will get drunk-up too fast to matter"?

Lots of screwing going on here.   ;D
Many of us would be on a strict liquid diet if it weren't for pretzels.

Offline Stevie

  • Official Poobah of No Life.
  • *
  • Posts: 6858
    • View Profile
Re: Keg dry hoping + keg purge, how to do that?
« Reply #1 on: June 26, 2017, 01:10:26 AM »
I just pop it open and hope for the best. I do try to move quickly. Connecting a gas line to the liquid post and letting it run on low might be a solid plan.

Offline Philbrew

  • Brewmaster
  • *****
  • Posts: 866
    • View Profile
Re: Keg dry hoping + keg purge, how to do that?
« Reply #2 on: June 26, 2017, 01:15:31 AM »
I just pop it open and hope for the best. I do try to move quickly. Connecting a gas line to the liquid post and letting it run on low might be a solid plan.
Hmmm,  Good thought.
Many of us would be on a strict liquid diet if it weren't for pretzels.

Offline The Beerery

  • Senior Brewmaster
  • ******
  • Posts: 1499
  • More you know, the more you know you don't know!
    • View Profile
Re: Keg dry hoping + keg purge, how to do that?
« Reply #3 on: June 26, 2017, 02:14:29 AM »
Real low. Due to gas mixing laws you want to stop as much swirling as possible.


Sent from my iPhone using Tapatalk
Herr, wirf Hirn vom Himmel!
(Oder Steine, Hauptsache er trifft.)
Check us out at www.lowoxygenbrewing.com (Now with forums)
"Consistently successful brewers are invariably the ones who operate low oxygen systems." -George Fix Circa 1999
Taplist and Fermentation Cellar
"Progress is impossible without change, and those who cannot change their minds cannot change"

Offline Stevie

  • Official Poobah of No Life.
  • *
  • Posts: 6858
    • View Profile
Re: Keg dry hoping + keg purge, how to do that?
« Reply #4 on: June 26, 2017, 02:17:03 AM »
Real low. Due to gas mixing laws you want to stop as much swirling as possible.


Sent from my iPhone using Tapatalk
No doubt, just enough to hear it. Using the gas post would likely cause issues here as well.

Offline HoosierBrew

  • Global Moderator
  • I must live here
  • *****
  • Posts: 13030
  • Indianapolis,IN
    • View Profile
Re: Keg dry hoping + keg purge, how to do that?
« Reply #5 on: June 26, 2017, 02:24:02 AM »
I purge the keg, then open to add the hop bag quickly, with 2 or 3 lbs of CO2 blowing in the keg when I pull the lid.
Jon H.

Offline blatz

  • Official Poobah of No Life.
  • *
  • Posts: 3423
  • Paul Blatz - Jupiter, FL
    • View Profile
Re: Keg dry hoping + keg purge, how to do that?
« Reply #6 on: June 26, 2017, 05:41:47 PM »
my new method is to conduct the usual purge method (fill to overflow with sanitizer, push out with CO2) then degas keg, hook gas up to the liquid post and run 2-3PSI and pop in the hops quickly and reseat the lid asap.  then proceed as normal, filling the keg under pressure.

The happiest people don’t necessarily have the best of everything; they just make the best of everything they have.

BJCP National: F0281

Offline kramerog

  • Senior Brewmaster
  • ******
  • Posts: 1809
    • View Profile
    • My LinkedIn page
Re: Keg dry hoping + keg purge, how to do that?
« Reply #7 on: June 26, 2017, 06:05:39 PM »
1. Push starsan out.
2. Transfer beer through out post
3. Open and put hops in quickly
4. Close
5. Purge headspace ~ 4 times by pressurizing Keg with CO2 to 5-10 psi and pull vent.

I don't blow in CO2 while keg is open because I believe headspace purging to have a sounder theoretical basis.


Offline brewsumore

  • Brewmaster
  • *****
  • Posts: 622
  • Spokane, WA
    • View Profile
Re: Keg dry hoping + keg purge, how to do that?
« Reply #8 on: July 04, 2017, 12:21:17 AM »
For IPA and pale ale, before racking finished beer from fermenter buckets into kegs via an auto-siphon, I just lower an open-ended sanitized gas line from a spare 5-lb co2 tank with gauge, down towards the bottom of the sanitized empty receiving keg and gently/slowly add co2 gas until it blows out a lighter (the long one used to light a BBQ grill) held above the keg opening.  That is, once co2 displaces all of the oxygen from the keg the outgoing co2 blows out the lighter.  Then I add a keg lid until I'm ready to rack in the beer.  co2 is heavier than o2 so the co2 stays in there during racking.

Then I add keg hops in a sanitized fine-mesh nylon hop bag, cinched and knotted closed, and tied into the hole in the welded tab on the underside of a keg lid.  I buy these manufactured - a bit spendy but most people only need one, a couple, or a few of them.

After the beer is racked into the keg, I lower the hops-filled bag (normally a 9" x 12" bag holding 3 oz pellet hops) that is tied off to the lid, and secure the keg lid.

Then I immediately purge the keg head space as follows: 1) attach co2 gas to "in" poppet via QD, 2) fill head space with co2 at ~12 psi, 3) turn off gas, 4) displace all gas/air in headspace via pressure release valve, 5) repeat for a total of 10 times, 6) begin to carbonate the beer in my kegerator.

 

Offline The Beerery

  • Senior Brewmaster
  • ******
  • Posts: 1499
  • More you know, the more you know you don't know!
    • View Profile
Re: Keg dry hoping + keg purge, how to do that?
« Reply #9 on: July 04, 2017, 12:32:05 AM »
Co2 is heavier than air, yes, however not by much.  It doesn't really stratify like folks think.


Sent from my iPhone using Tapatalk
Herr, wirf Hirn vom Himmel!
(Oder Steine, Hauptsache er trifft.)
Check us out at www.lowoxygenbrewing.com (Now with forums)
"Consistently successful brewers are invariably the ones who operate low oxygen systems." -George Fix Circa 1999
Taplist and Fermentation Cellar
"Progress is impossible without change, and those who cannot change their minds cannot change"

Offline Stevie

  • Official Poobah of No Life.
  • *
  • Posts: 6858
    • View Profile
Keg dry hoping + keg purge, how to do that?
« Reply #10 on: July 04, 2017, 12:37:42 AM »
It's about 37.5% heavier than oxygen. The issue is, with convection, it all mixes up readily..

Offline The Beerery

  • Senior Brewmaster
  • ******
  • Posts: 1499
  • More you know, the more you know you don't know!
    • View Profile
Re: Keg dry hoping + keg purge, how to do that?
« Reply #11 on: July 04, 2017, 12:46:06 AM »
It's about 37.5% heavier than oxygen. The issue is, with convection, it all mixes up readily..
Ideal gas laws are a bia bia.


Sent from my iPhone using Tapatalk
Herr, wirf Hirn vom Himmel!
(Oder Steine, Hauptsache er trifft.)
Check us out at www.lowoxygenbrewing.com (Now with forums)
"Consistently successful brewers are invariably the ones who operate low oxygen systems." -George Fix Circa 1999
Taplist and Fermentation Cellar
"Progress is impossible without change, and those who cannot change their minds cannot change"

Offline brewsumore

  • Brewmaster
  • *****
  • Posts: 622
  • Spokane, WA
    • View Profile
Re: Keg dry hoping + keg purge, how to do that?
« Reply #12 on: July 04, 2017, 01:02:14 AM »
Using a 1/2" autosiphon with racking tube to the bottom of the keg I can fill a purged keg with beer in the matter of a few minutes.  Seeing that the keg is completely full with co2 to start with I'm pretty confident that very little o2 is getting to the beer.  At least I'm the only one I have to satisfy and I'm ok with my method.  I like not having any star san residing in my keg - just beer.  Each to their own.
« Last Edit: July 04, 2017, 01:04:38 AM by brewsumore »

Online coolman26

  • Brewmaster
  • *****
  • Posts: 778
    • View Profile
Re: Keg dry hoping + keg purge, how to do that?
« Reply #13 on: July 04, 2017, 02:06:04 PM »
Using a 1/2" autosiphon with racking tube to the bottom of the keg I can fill a purged keg with beer in the matter of a few minutes.  Seeing that the keg is completely full with co2 to start with I'm pretty confident that very little o2 is getting to the beer.  At least I'm the only one I have to satisfy and I'm ok with my method.  I like not having any star san residing in my keg - just beer.  Each to their own.
Your process is similar to mine. It is the best I can do for now. I would like to do closed transfers. I just haven't put it all together. I've not been keg hopping with a bag. I'm going that route on my IPA that is coming up. I have bought a mound of equipment pieces for changes. I'm too busy to get it done. I'm also thinking about keg conditioning to clean up some 02 in my less than perfect filling. 


Sent from my iPhone using Tapatalk
Jeff B

Offline The Beerery

  • Senior Brewmaster
  • ******
  • Posts: 1499
  • More you know, the more you know you don't know!
    • View Profile
Re: Keg dry hoping + keg purge, how to do that?
« Reply #14 on: July 04, 2017, 02:09:56 PM »
Using a 1/2" autosiphon with racking tube to the bottom of the keg I can fill a purged keg with beer in the matter of a few minutes.  Seeing that the keg is completely full with co2 to start with I'm pretty confident that very little o2 is getting to the beer.  At least I'm the only one I have to satisfy and I'm ok with my method.  I like not having any star san residing in my keg - just beer.  Each to their own.

Trim your gas dip tube short, as it basically serves no purpose anyways (I do flush). After the push out invert the keg, tilt towards the gas post and attach the QD, it will push all all remaining sani. Due to gas mixing laws, that is the only way for us that use corny's to get a good purge. Even then its not perfect. Vacuum and purge on a sanke is where its at.
Herr, wirf Hirn vom Himmel!
(Oder Steine, Hauptsache er trifft.)
Check us out at www.lowoxygenbrewing.com (Now with forums)
"Consistently successful brewers are invariably the ones who operate low oxygen systems." -George Fix Circa 1999
Taplist and Fermentation Cellar
"Progress is impossible without change, and those who cannot change their minds cannot change"