Fermenting Under Pressure

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Hoffdegg said:
Hi Wobbly,

Im really interested in your method as it seems so quick, especially for lagers. I have just finished my lager in the traditional way (2 week at 9 degrees then 4 weeks at 4 degrees to lager) and it's way to long to wait!
I have just ordered myself a kegking pressure fermenter. Looking forward to testing it out...

When you do it your method under pressure, do you get a sulphar taste in the beer? Not that I or those that drink my beer can tatse
Do you still have to condition/lager the beer as you normally would have to with a lager? I don't normally brew lagers but the two that I have I have started drinking after about 9-10 days and they have lasted in the machine for about a few weeks and I haven't noticed any age related conditioning effects over time.
So it is pretty much ready to drink after 7 days? And it matches up with a lager that has been fermented over 6-8 weeks? In the Machine/Fermenter I have the standard cycle using dry yeast is 3 days at 15C followed by a further 3 days at 18C then cold crash to 1C for 12 hours to drop yeast out followed by two days of clarification phase using Silica Dioxide. All of this is carried out with the pressure relief valve set at 1.5bar
The high pressure doesn't do anything to the yeast and produces a nice clean tasting lager? I ferment at 1.5bar (21psi) and that has no detrimental effect on the yeast. Think about a large brewer where the tanks are 10 meters high and the pressure at the bottom of the tank is about 1.5bar. My understanding is that at pressure above 3 bar you will start to impact on yeast health
Can yoh pitch off the yeast cake after fermenting at thag pressure or does the pressure kill the yeast over time? Can't comment as I have never tried this with either lager or Ale yeast but I don't see why you couldn't harvest yeast for reuse after washing etc
Any information you can be given will be very much appreciated... You might want to down load the user manual from this site as that may be a good starting point for you http://www.williamswarn.com/Our-User-Manuals#.Vxgssf2Q-M8
Hoff
I have not seen the Keg King Pressure Fermenters so I'm not in a position to comment. The machine I use has been designed to do a number of sequences I mentioned in post #16 so I don't have to worry about things like temperature and pressure control, yeast harvesting, cold crashing, clarification and serving but hey that comes at a price (which I was and still are) happy to pay. It's not necessary to leave the finished beer in the machine until it is all consumed it is easy enough to transfer the carbonated beer to bottles or a keg if that suits you

As stated above down load this manual and have a read as it may answer a few of your questions http://www.williamswarn.com/Our-User-Manuals#.Vxgssf2Q-M8 There is also a hundred pages plus on the subject on Homebrewtalk that can be viewed at this thread. http://www.homebrewtalk.com/showthread.php?t=44344

Happy for you to PM me if you think I can be of further assistance

Cheers

Wobbly

edit for spelling
 
wobbly said:
OK at the risk of copping a bagging (again) I will offer details on the standard Williamswarn process for pressure fermenting
  • Set the VPRV (spuding valve) to control at 1.5bar (21psi) for both Lagers and Ales - No issues with my brews (I haven't brewed any Belgians or Stouts) but the recommended procedures are the same
  • Fermentation temperatures using dry yeast - Ale 23C for 4 days by which time terminal gravity is achieved PIlsner/Lagers 15C for 3 days followed by 18C for a further 3 days "D" rest - No issues with my beers
  • At terminal gravity cold crash to 1C in one setting from fermentation temp and hold for 12/24 hours so as to drop the yeast out of suspension - No need to set temp to change in small daily increments
  • I have brewed with US-05, Nottingham, W34/70, S23 and SO4 with no noticeable issues with the above temp/pressure/time regimes
  • Following dropping the yeast then I clarify using a Colloidal Silica product at a rate of 2mls per liter over 24/36 hours and then consume
Wobbly
 
Hi Wobbly,

Im really interested in your method as it seems so quick, especially for lagers. I have just finished my lager in the traditional way (2 week at 9 degrees then 4 weeks at 4 degrees to lager) and it's way to long to wait!
I have just ordered myself a kegking pressure fermenter. Looking forward to testing it out...

When you do it your method under pressure, do you get a sulphar taste in the beer?
Do you still have to condition/lager the beer as you normally would have to with a lager?
So it is pretty much ready to drink after 7 days? And it matches up with a lager that has been fermented over 6-8 weeks?
The high pressure doesn't do anything to the yeast and produces a nice clean tasting lager?
Can yoh pitch off the yeast cake after fermenting at thag pressure or does the pressure kill the yeast over time?
Any information you can be given will be very much appreciated...
Hoff
 
Thank you very much for all this information. Can't wait to give it all a go, guess all you can do is experiement/trial and error.

Thanks again
Hoff
 
The 7 day cycle for Ales and 9 days for lagers is predicated on the basis that you can or are able to progress seamlessly from one step to the next using the machine/fermenter I have.

Being able to drop/dump the yeast at the end of fermentation is basically the same as could be achieved with a conical that has a bottom dump vale fitted - On my machine it requires no intervention, just happens and you can see where it is at.

The clarification phase is also easier as the system is built to be able to "Inject" it into the beer without having to release the Co2 pressure and open the device and thereby letting in Oxygen which isn't really desirable. Undoubtedly you could rig something to carry this phase out using a/the racking port somehow and "Inject" the clarification liquid in with Co2 pressure

I use Colloidal Silica Dioxide as my clarification liquid in preference to Gelatin as a personal preference for Mineral additions rather than Animal based

As for aging Lagers/Pilsners I don't see the need as the two I have brewed have turned out fine after 9 to 10 days "grain to brain". People talk about the need to allow the beer to "clean itself up" and I'm not sure just what they mean by this. If it's allowing time for the yeast to come out of suspension and take with it some of the sulfur taste then the clarification phase on my machine does this in a mater of a couple of days.

There is another topic on here somewhere that talks about using modified kegs to ferment under pressure and in that topic they mention that the lagers fermented under pressure are very clean to the taste and don't require the so called mandatory weeks of conditioning etc but I'm not sure if they also use some form of clarification liquid. I'm not knocking those that see it as being necessary brewing under atmospheric conditions it's just something I and others have found to not be required when pressure fermenting.

Cheers

Wobbly
 
What's the highest pressure anyone has gone up to during the active ferment?

I just got back from a work trip, I had a munich dunkel fermenting at 10 degrees at 15 psi for 10 days before I left and thought it was close to done so I capped the fermenter. It was a pitch onto a previous yeast cake of 2308 and only my second lager under pressure. I got back today and tried to put on the spunding valve and the pressure guage flatlined. I released what seemed like heaps of pressure to get it back down to 15 psi. So how high have the pressure fermenters among us gone?

I wiill update after a sample.
 
neal32 said:
What's the highest pressure anyone has gone up to during the active ferment?

I just got back from a work trip, I had a munich dunkel fermenting at 10 degrees at 15 psi for 10 days before I left and thought it was close to done so I capped the fermenter. It was a pitch onto a previous yeast cake of 2308 and only my second lager under pressure. I got back today and tried to put on the spunding valve and the pressure guage flatlined. I released what seemed like heaps of pressure to get it back down to 15 psi. So how high have the pressure fermenters among us gone?

I wiill update after a sample.
This was discussed in another thread, you should be fine, maybe a lil over carbed perhaps?!
 
The sample tasted great and it was at 1.011. I'm slowing bleeding pressure until I get to 15 psi and then will recap, do a d-rest(unnecessary based on the sample but good practice) then down to 4 degrees for a couple of weeks until a keg frees up
 
What type of spunding valve have you got on youre set up Neal
 
Like so many things it is not a wonder drug, but it works. I started mucking about in a very manual way some years ago after reading about german lager production. At the time I was unaware of the other factors such as ester reduction, but became after the publication of the excellent book "Yeast" by Chris White and Jamil Zainasheff. The Keg King Spundling valve was a godsend for me !!
I ferment most of beers under pressure in either Fermentokegs or quickies in 9 litre party kegs. My normal pressure is 0.5 to 0.8bar (say 10psi) and my normal batch 27 to 30 litres in a Fermentokeg.
Overall observation is that the quality of the beer does not improve, the fermentation time is the same as normal, there may be some reduction of esters in lagers but this is not apparent in ales.
I have noted, however, that this is a very good way to make high alcohol beers (say triples).
So apart from high ABV which I rarely make, why bother?
----I seriously like pouring beer and drinking it straight from the fermentor
---So long as I keep my pressure below a bit under a bar there will be no detrimental effects on the yeast,I can dispense half a keg or so out the fermentor, keg the remaining on my next brew day and just ferment on the yeast cake without wasting energy cleaning the fermentor
---The totally closed (no way in) environment is the perfect match for my septic (to some) brewing practices......

K
 
You could no chill, ferment and dispense all from the same vessel drK.

Like VB??
 
I guess that depends on your recipe. To each their own. I won't judge you.
 
Hi,

I am extremely keen to purchase one of the oxebar pressure fermenters but have a few questions about pressure fermenting?

1. Do I need spunding valve to achieve this and why, could I not just carbonate using my existing keg system instead?
2. Do I need to connect relief valve to my CO2 tank before connection to fermenter so I don't accidentally over pressurise it?
3. Do I need to connect my CO2 tank to fermenter after transferring wort or should I let pressure build naturally?
4. I have read that pressure fermenting reduces fermentation periods, is this the case and do you have any guidelines you could point me towards?
5. I note that brewery's that pressure ferment put their dry hops in fermenter straight away, is this something we can do with your fermenter and do you know what sort of ratio of dry hops to use?
6. Do I need to add CO2 from my bottle to transfer finished beer to keg?
7. Is opening from valve to collection bottle large enough that muck/yeast doesn't get stuck when trying to dump/collect?
8. Lastly I am real keen on using fresh fruit such as watermelon in the later stages of fermentation, how would you add these to a pressure fermenter such as yours?

Many thanks for your response in advance,

Cheers
Callum

Sent from my iPhone
 
Hey there,

I recently bought one of these Oxebar jobbies and am fermenting a blonde ale in it now. I'll see if I can answer some of your questions...

Wnkmox said:
1. Do I need spunding valve to achieve this and why, could I not just carbonate using my existing keg system instead?

You don't need a spunding valve and the default package doesn't come with the pressure kit so unless you intend on fermenting under pressure you can just use the normal type of bubbler airlock that comes with the fermentasaurus. If you do intend to femrent under pressure with the pressure kit you could probably get away with attaching a quick disconnect to a hose and making a type of blow off vessel. Or you could periodically vent the PRV on the lid. You just won't be able to regulate it is all. I do believe the PRV is set to rlease pressure at a certain point for safety but that point may be too high for your desired CO2 level.

2. Do I need to connect relief valve to my CO2 tank before connection to fermenter so I don't accidentally over pressurise it?

To connect your fermenter to your CO2 tank, as long as you have a one-way check valve on your gas line, that should cover any back blow that could occur from the pressure inside the fermenter to the regulator. Otherwise you just attach your gas line to the post on the fermenter and slowly crank up the pressure inside until your CO2 regulator reads what you want it to for whatever it is you are doing, ie. transferring to keg, purging, carbonating.

3. Do I need to connect my CO2 tank to fermenter after transferring wort or should I let pressure build naturally?

The pressure will build naturally as the wort ferments and turns into beer. There is just no-where for it to go when it is under pressure so it stays in solution in the beer up to the point at which any spunding valve is set to.

4. I have read that pressure fermenting reduces fermentation periods, is this the case and do you have any guidelines you could point me towards?

This was something I was unaware of but from the single batch I have done, it would seem to be the case. I had a batch of Blonde Ale with an OG of 1.042 and pitched a starter of 1272 American Ale 2. I think it was at 1.010 within about 4 days, maybe even sooner, that was my first check I have no guidelines, I'm sorry!

5. I note that brewery's that pressure ferment put their dry hops in fermenter straight away, is this something we can do with your fermenter and do you know what sort of ratio of dry hops to use?

I'm not usually one to dry hop that much but I wanted to give it a go with this new bit of kit because it looked like an interesting process. Once I saw that the beer was pretty much ready, I removed the dump bottle/yeast collection jar thingy, emptied the trub that had been collected in it. I then cleaned the jar, sanitised it with star-san and put about 20g of Cascade pellets in, flushed that with some CO2 and then rescrewed the jar onto the base of the fermenter. Open the butterfly valve, flush she goes, the hops get all swirled around with the brief change in pressure so the rise to the top, swill about a bit, get a bit of rehydration in the wort and then gradually begin to settle back down into the bottom and eventually back into the jar having done their job. That sediment is then away from the beer due to the conical shape and easy to leave behind or discard. Quite ingenious.

6. Do I need to add CO2 from my bottle to transfer finished beer to keg?

You could probably use a bit of the pressure from the fermenter but it wouldn't push the entire volume over to a keg. Take the spunding valve off, whack it onto your totally pressurised keg, making sure the valve is closed. Then attach the CO2 to the fermenter, but not with the gas on. Attach the liquid out post on the fermenter to the liquid out post on the keg, ease open the CO2 on your cylinder and ease open the valve on the spunding valve until you have a gradual transfer from fermenter to keg. Totatlly closed system.

7. Is opening from valve to collection bottle large enough that muck/yeast doesn't get stuck when trying to dump/collect?

It's a satisfactory size. Certainly big enough to collect anything you could think of that needs collecting/dumping. There's always going to be a bit of gunk lurking around when you are dealing with trub/yeast/sediment. I should probably spray the opening with star san or some other cleaning agent before reattaching the jar. I'll try that next time. Also if it is fermenting under pressure, unscrewing that jar can be fizz central so make sure there is a tray underneath and do it really slowly or you'll get a face full of yeast.

8. Lastly I am real keen on using fresh fruit such as watermelon in the later stages of fermentation, how would you add these to a pressure fermenter such as yours?

I may have to pass that one on to someone with a bit more knowledge about brewing with fruit but I guess you could always add it to the collection jar. Anything added to that gets shot up into the fermenter when the butterfly valve is opened again due to the pressure differential. So anything you can fit into that jar, and it's not really that big, you could theoretically add to your fermeneter.
I hope that helps.
It's a pretty awesome bit of gear actually. Bulky though. Make sure your fermentation has the space to accommodate it. Keg King have the measurements on their site and it's worth checking that before your drop your hard earned.
Here's how it looks in my ferm fridge.
2017-04-04 15.10.07.jpg

Goddamn image orientation! How does that even happen?

If anyone has any other questions, I'll do my best to help where I can.

Cheers,
John
 
Excellent points.
I have a Fermentasurus, in fact I have three, and have made cider and a number of ales in them.
To say that they are fantastic is almost an understatement, its suprising but its actually nice to watch the ferment.
I ferment chill and dispense,that floating pickup works a treat, when I need it again I keg whats left and clean it out (incredibly easy) maybe I keep the yeast, maybe not.
I use WLP002 a hell of a lot and its pretty easy to recover....

K
 
Pity they don't have a squatter version that would fit in their own KegMate (I have 3).
 
Thanks heaps for replays, very helpful. I have made the leap and purchased one, just waiting for it to arrive. Couple further questions, has anyone fermented to the Williams warns schedule and has anyone dry hopped 50-100g and if so how? Thanks in advance!
 

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