Questions of Pressure Fermentation

[msa8967]

Not sure if there is a special section for questions of fermenting under pressure (if so please let me know to post there). Looks like my spunding valves got clogged up in my first few efforts for fermenting under pressure in 5 gallon corney kegs so the beer pressure climbed to the 20-25 psi range for ales for about 12-24 hours on day four of fermentation. I might have had to little head space so kraussen got pushed through the valves. Is this going to really affect the end results and how much head space do others leave in a 5 gallon keg? My initial gravity was at 1050 and I used a full packet of US-05 Yeast. Thanks for any input you might have.

 

[11thStBrewing]

That should be just fine. Some people up the pressure to 30-35PSI towards the end of fermentation at ale temps so the beer is naturally fully carbonated when it’s done fermenting.

Cheers!

 

[Bassman2003]

You will be fine. The beers taste more "commercial" as you get towards 20 to 30 PSI. I brew lagers with a 30 PSI starting pressure and keep it there the entire ferment.

As far as head space, I do not know.

 

[msa8967]

Thank you.

 

[jackbflyin]

Here a video with pressure fermentation information.

 

[Clint Yeastwood]

I put Fermcap in my fermenter last time I used pressure. I wanted to keep the foam down. I also use a 6-gallon keg.

 

[odie]

I've rarely had any issues with krausen blowing out my spunding valve. I get a full 5 gal in the keg and target around 5-10 psi for lagers.

For ales I've always used a blow off tube for the first few days and then switch to a spunding valve.

Both ales and largers I will remove the spunding valve towards the end and let the PSI rise to the PRV venting point. But I use the "red" PRV valves which are in the 25-30 PSI range.

 

[100miles]

i am starting to pressure ferment using the FermZilla allrounder and spunding valve blow tie type. I wanted to ask that just after i pitch in yeast should i keep my spunding valve closed to let pressure build up for atleast 1 day or if i shall let it slight open then how much ?

 

[Bassman2003]

Yes, keep it closed and monitor as the yeast start putting off CO2. As the pressure builds to your desired fermenting pressure, then open the valve just enough to where you get a release. The batch will then stay at that pressure until you change it. I know this as a "natural build" as opposed to pressurizing the fermenter with CO2 from the start. For hoppy beers, pressurizing from the start with a certain amount of CO2 really keeps the hop aroma and flavor. Lots to experiment with in pressure fermenting.

 

[VikeMan]

i am starting to pressure ferment using the FermZilla allrounder and spunding valve blow tie type. I wanted to ask that just after i pitch in yeast should i keep my spunding valve closed to let pressure build up for atleast 1 day or if i shall let it slight open then how much ?

Set your valve to begin releasing pressure at whatever pressure you want to ferment at. It will be functionally "closed" until the pressure reaches that set point. There's no reason to keep it completely closed (by cranking it all the way tight) at any time. In fact, there's a geed reason not to, which is safety (if your setup doesn't also include an emergency PRV).

 

[Bassman2003]

Somewhere in the middle between what VikeMan and I posted! I know from my spunding valves that an unpressurized fermenter makes the spunding valve setting a guess. Yes, as long as your spunding valve is set to BELOW your PRV safety pressure, you are good. "Closed" is sort of relative but safety always has to be a concern with pressure vessels.

 

[100miles]

Yes, keep it closed and monitor as the yeast start putting off CO2. As the pressure builds to your desired fermenting pressure, then open the valve just enough to where you get a release. The batch will then stay at that pressure until you change it. I know this as a "natural build" as opposed to pressurizing the fermenter with CO2 from the start. For hoppy beers, pressurizing from the start with a certain amount of CO2 really keeps the hop aroma and flavor. Lots to experiment with in pressure fermenting.

thanks for your advice. its been 24 hours there are visible signs of fermentation bubbles . however the pressure is still at 0 bar , with closed valve. However, I am only fermenting 2 gallons using pilsner malt with Lutra kveik yeat(added 4.5gms) you think it might take more time to build pressure due to low height of wort inside fermenter. can i check if my allrounder is leaking now ? it gives a slight yeast smell but I am not sure if that can be concluded as leak ? ( i ordered a co2 cylinder and attachments which will arrive in 4-5 days so i can check leakage as well as pressurize enough if needed )

 

[100miles]

Set your valve to begin releasing pressure at whatever pressure you want to ferment at. It will be functionally "closed" until the pressure reaches that set point. There's no reason to keep it completely closed (by cranking it all the way tight) at any time. In fact, there's a geed reason not to, which is safety (if your setup doesn't also include an emergency PRV).

yes got PRV

 

[Clint Yeastwood]

I have learned to shoot CO2 into fermenters at the start to make sure they're sealed.

 

[Bassman2003]

Yes, a leak check is always the first thing if zero is reading but there is plenty of yeast activity.

 

[IDMaynard]

You should be able to spray a little StarSan (or soapy water) on all the joints to see if you have a leak, or just listen for escaping CO2.

 

[Dr_Jeff]

I've fermented under pressure for years, and currently use kegmenters, that have the red 25-30 psi PRVs, and they stay on from beginning to end.

 

[DuncB]

Take the spunding valve off and have a listen, you might hear a leak. Check the seals on the red caps with some soapy water spray.

Leave the vessel for a couple of hours and then put spunding valve back on and it should read a pressure if no leak in vessel. If gas gushes out of spunding valve then tighten it up.

 

[DuncB]

Is your ball lock connector fully on? I can't fully tell from the picture but it looks a bit high, lift the collar on the connector and push it down hard it should then click into place.
This might be why the reading is zero at the moment.

 

[Clint Yeastwood]

There are a billion ways to skin a cat. Especially a neighbor's cat that walks on your car's hood and leaves footprints. But I would consider getting a 6-gallon Torpedo keg for fermenting. The All-Rounder is neat, but the manufacturer admits they eventually turn into bombs when used under pressure.

The manual doesn't actually contain the word "bomb." I added that part.

 

[DuncB]

Anyone near a red gas connector and post to confirm whether that connection is on correctly? Zoom in on the photo.

 

[100miles]

Is your ball lock connector fully on? I can't fully tell from the picture but it looks a bit high, lift the collar on the connector and push it down hard it should then click into place.
This might be why the reading is zero at the moment.

you were right, it was not fully closed. thanks for pointing out. So I eventually had my poressure regulator for Co2 cylinder and now I pumped in 23 psi of CO2 inside. This force carbonation, how long does it take as after 24 hours I am seeing a drop in pressure to 12 psi. I dont hear any hissing sound so I am thinking the drop is due to the dissolved Co2 in liquid part. is that correct ?

 

[100miles]

So I eventually had my pressure regulator for Co2 cylinder and now I pumped in 23 psi of CO2 inside. With this forced carbonation, how long must i wait ( are there any clues or readings to look out for ) as after 24 hours I am seeing a drop in pressure to 12 psi. I dont hear any hissing sound so I am thinking the drop is due to the dissolved Co2 in liquid part and not leak. is that correct ?