Pressure lagering

[Animus75]

I was thinking about trying pressure fermenting , i heard that it accelerates the fermentation process , but how do a calculate the fermentation time, for example ; some lager can take up to 4 weeks at conventional method , but under pressure it goes much faster , how do i know how long?
if someone can help

thank you

 

[Pappers_]

Welcome to HBT, Animus. I can't help you with your question, but you might just not worry about predicting the fermentation time and just monitor it for when its finished.

Also, I've moved this from the Introductions forum to the Fermentation forum

 

[ebbelwoi]

OK, I'll take a stab at this. First off, you're talking about fermenting a lager under pressure, so the title Pressure lagering doesn't quite fit your question.

I've done a few small pressurized lager batches. From what I understand (and someone please correct me if I'm mistaken), it's not the pressure that lets you ferment a lager faster. It's the higher temperatures. The pressure helps suppress the esters that would normally form at higher temperatures.

I haven't tried this yet, but I would fill a 500ml or 1L PET soda bottle with the same wort and yeast as in your pressurized batch, but ferment it without pressure. Use that to check your gravity. When that one's done, your pressurized batch should be done, too. Theoretically. Can anyone confirm this?

 

[Iseneye]

Pitch the right amount of healthy yeast and you won't need to muck around with pressure fermentation.

 

[Animus75]

Thanks guys

 

[jimmypop13]

I just finished a keg of a beer I made with w34/70 in my closet with 20psi of pressure. Took around 5 days to hit fg. Then i cold crashed at 34* and added gelatin and waited a few days. The beer was great. No pronounced yeast character, no sulfur, no esters or off flavors. I would definitely recommend trying it if you don't feel like getting a fermentation fridge

 

[Nathan Graen]

Is there a need to do a diacetyl rest? If you're already at room temperature, would that be blowing off the pressure?

Also, if I'm going to pressure ferment in five gallon corny kegs, do I need to scale my batches down to four gallons to allow adequate headspace, leaving only 3.5 gallons of finished beer above the trub?

 

[Vale71]

There's no need to do a diacetyl rest at those temperatures. That's one more factor that accelerates production by shortening the conditioning phase as well, which is the main reason pressure fermentation of lagers is done at commercial breweries.
If you have issues with blow-off and don't want to lose capacity you should consider using some form of anti-foam agent.

 

[renstyle]

I just finished a keg of a beer I made with w34/70 in my closet with 20psi of pressure. Took around 5 days to hit fg. Then i cold crashed at 34* and added gelatin and waited a few days. The beer was great. No pronounced yeast character, no sulfur, no esters or off flavors. I would definitely recommend trying it if you don't feel like getting a fermentation fridge

5 days is sweet!

Had a few questions:

What vessel were you doing the pressure ferm in? conical/fermzilla/corny?

What spunding solution worked for you? I've got a blowtie but thinking of doing a DIY valve also.

Are you able to introduce the gelatin O2 free? (syringe or pressurized bottle)?

What was the ambient temp that helped hit FG in 5 days?

I'm fermenting ales in corny kegs and would hope to someday mirror your results with a lager.

 

[renstyle]

Also, if I'm going to pressure ferment in five gallon corny kegs, do I need to scale my batches down to four gallons to allow adequate headspace, leaving only 3.5 gallons of finished beer above the trub?

The yeast and temp will dictate some of the krausen height/activity, but for MOST batches sub-1.055 OG, I've had decent luck with a 4.5 gal batch size into ferm-keg in BeerSmith.

I picked up some FermCap, and use 1-2 drops per gallon either during the boil or in the ferm-keg just before pitching.

Use a blow off with a gas QD+hose first 3 days, then spund at pressure till FG is hit. I've seen ranges from 2-3 PSI all the way up to 20PSI (earlier in this thread) on the spund.

No blow offs, and using a floating dip tube in the ferm-keg, I was able to retrieve 4 gal into the serving keg.