Primary time during pressure fermentation?

[Feasterbrew]

Trying out pressure fermentation in a corny for the first time. Fermentation is going well with diamond lager going as expected with my 1.053 wort at 64 deg F and 12 PSI. Now for the question, does anyone with experience typically bump up the temp during pressure fermentation for a diacetyl rest even though the fermentation temp is already elevated to 64 deg F? How long do you typically rest for yourself? I am away on vacay so it'll be about a week rest so not expecting an issue but more curious to see what people do!

 

[DuncB]

I do tend to bump up a couple of degrees C, although these days using ALDC I probably don't need to bother.
I would ask in this thread as you'll see it's been a busy one.

https://www.homebrewtalk.com/threads/warm-fermented-lager-thread.592169/

 

[Franktalk]

I am pretty sure that pressure fermentation suppresses diacetyl, so you'll be fine at 64F.

 

[DuncB]

I am pretty sure that pressure fermentation suppresses diacetyl, so you'll be fine at 64F.

Not sure about this, it suppresses esters and sulphurs but lots of commercial breweries using cylindroconicals use ALDC and this would be a waste if not necessary.

 

[Franktalk]

Look for the podcast by John Blichmann with Chris White as a guest. They did some batches at homebrew sizes and shared the data, and it showed a reduction in diacytel at all pressures and temps. See attached findings.

 

[Feasterbrew]

I do tend to bump up a couple of degrees C, although these days using ALDC I probably don't need to bother.
I would ask in this thread as you'll see it's been a busy one.

https://www.homebrewtalk.com/threads/warm-fermented-lager-thread.592169/

I was looking for something like this! Thank you. New to the forum and figuring out the best way to navigate to find info.

 

[Feasterbrew]

Look for the podcast by John Blichmann with Chris White as a guest. They did some batches at homebrew sizes and shared the data, and it showed a reduction in diacytel at all pressures and temps. See attached findings.

Awesome info! Thank you

 

[Jag75]

While pressure fermenting does help with reduction of diacetyl, its not an end all. You still should do a rest. However your at about that temp were diacetyl rests are done . So you might be just fine, but it wouldn't hurt to bump up a tad towards the end of your fermentation.

 

[Broothru]

While pressure fermenting does help with reduction of diacetyl, its not an end all. You still should do a rest. However your at about that temp were diacetyl rests are done . So you might be just fine, but it wouldn't hurt to bump up a tad towards the end of your fermentation.

Agree. When doing pressure fermentations I usually target 63F-65F, and 1 BAR/14.7 psig. When at or near 5 points of predicted FG (Specific Gravity, not Plato) I increase temp 5-7 degrees F for lagers and 7-10F for ales and hybrids, maintaining 1 BAR, and hold for three days.

Probably overkill because I also add ALDC enzyme when pitching the yeast, so in theory there should be no diacetyl anyway. Between the pressure fermentation, ALDC, and d-rest, diacetyl in the finished beer exists only in the mind of the judge who needs something to criticize.