Closed-system pressurized fermentation technique! - Page 27

**lamarguy** · 12-21-2009, 03:49 PM

Here's an action shot from last Saturday when I coarse filtered (5 micron nominal) my London Porter straight from the fermenter.

I cold crashed to ~30F to promote yeast flocculation and prevent foaming, purged and pressured the destination keg to 6 psi (via the spunding valve "dongle"), and maintained 9 psi in the fermenter (via the small CO2 tank). With a 3 psi pressure differential, it took about 15 minutes to rack and filter 5 gallons of carbonated beer (2.5 volumes). No foaming whatsoever.

In the future, I plan to experiment with dry hopping in the same filter housing using a coarse filter. Sparkling beers will get an absolute 1 micron filtration experience. The filters are reusable numerous times, so I'll likely start filtering on a regular basis.

aarondrich · 12-21-2009, 04:19 PM

Lamarguy, so did you jack up your spunding valve at the end of fermentation like we discussed earlier in the thread to get to 2.5 volumes? If so at what point?

**lamarguy** · 12-21-2009, 04:37 PM

Quote:

Originally Posted by aarondrich

so did you jack up your spunding valve at the end of fermentation?

Pressure steps (by day):

1 psi @ 66F
2 psi @ 66F
4 psi @ 66F
6 psi @ 66F
12 psi @ 69F

After I cold crashed to 30F, that left me with ~2 volumes of CO2 (pressure gauge read 3 psi). I then applied 7 psi of top pressure for 48 hours @ 30F to reach 2.5 volumes of CO2 in the fermenter.

**WortMonger** · 12-21-2009, 11:04 PM

lamarguy, how do you store your filters after use? Do you clean and then store? What's your technique?

**lamarguy** · 12-21-2009, 11:27 PM

Quote:

Originally Posted by WortMonger

lamarguy, how do you store your filters after use? Do you clean and then store? What's your technique?

Disassemble the housing and rinse off the excess beer.
Soak everything in a ~120F PBW solution (oxyclean is fine) for 30 minutes.
Reassemble everything and back-flush the filter using tap water pressure.
(Optional) Sanitize the filter using a non-staining/non-acidic sanitizer and allow to air dry. I use a commercial quat, same thing I use for sanitizing kegs.

Before each use, I give the dry filter a quick dunk is a no-rinse quat solution.

1 micron filter
5 micron filter

aarondrich · 12-28-2009, 06:57 PM

I've been reading the WIKI on lagering and there are charts that reference pressurized fermentation for lagering too? The wiki assumes that this isn't an option for home brewers, but obviously for this crowd that may be wrong. I was just curious if people have played around with this, and was curious as to what their schedule/process looked like?

I would love to try a lager since I have controlled fermentation temperature as of yesterday.

Thanks in advance!

**lamarguy** · 12-28-2009, 07:14 PM

Quote:

Originally Posted by aarondrich

I've been reading the WIKI on lagering...I was just curious if people have played around with this, and was curious as to what their schedule/process looked like?

Sacc posted earlier in this thread about his successful pressurized lager experiment. I tasted this beer and it was pretty clean, other than an green apple (acetaldehyde) note.

The key is to not raise the pressure higher than ~1 psi for the first 24 - 36 hours (36 hours for a 48F lager) and not got above 1 bar (14.5 psi) after that. Otherwise, yeast growth will likely be retarded to the point the beer may not fully attenuate.

**humann_brewing** · 12-28-2009, 07:55 PM

you guys are my hero, I need to get this going. I was wondering if you guys dry hop in your serving keg then. I see lamarguy wants to do so during the filter.

Also, how are you not picking up any trub or is that another benefit of using a filter?

aarondrich · 12-28-2009, 08:00 PM

I am new to this whole thing, but made an IPA as my first pressurized fermentation and did dry hop in the keg. Since it's carbonated already, the hop addition makes a lot of foam so be quick!!! I bought one of those large herb balls and put 1 oz of hops in it and it just sank to the bottom. I've read mixed replies as to whether or not this gives a grassy flavor, but I didn't have any available method to pull it out that day. So far so good, it's been in there a couple of months and tastes great.

aarondrich · 12-28-2009, 08:38 PM

Lamarguy, just to clarify, do you believe that keeping the first 36 hours at less than 1 PSI and also the total Pressure to under 14 PSI that it will eliminate the green apple taste?