Fementation temp profile for a lager?

[Charlie]

Hey! Anybody got a suggestion for a temp profile for fermenting a lager? I'm using WLP-820 Oktoberfest/Marzen (optimum temp 52-58F).

I brewed last Sunday (Jan 24) and pitched a 2L culture into 5 gallons. Then I put it in the FC at 68F overnight to establish activity (and it did), and then dropped the temp to 54F where it has been ever since.

I expect it to stay there for a couple more weeks, but what about a diacetyl rest? Do I need to bring the temp back up after it's done so the yeast can eat the diacetyl? What's my target temp, and for how long?

[cascadiabrewer]

No pitchy warmy, pitchy cooly!
Never drop temp after pitching lager yeast. Instead try to cool to 50ish degrees F then pitch. With a starter the wort will rise a couple of degrees and do its job. Fermet out around 54ish then you can raise the temp to 60 degrees for a diacetyl rest.
You are not encouraging the yeast to do their job by cooling the wort when they are just waking up hungry with a lot of food around, just slowing them down.

[brewinhard]

The last few years I have subscribed to Tasty's fermentation schedule for lagers (more or less). Basically I pitch a healthy starter (slurry only) into 48F wort and aerate heavily. Depending on the gravity I typically let it stay between 48-50F for about 5-7 days and as the krausen starts to drop back in to the beer, I gradually raise the temps 3-4 degrees F (or so) every couple days (to keep the yeast active, happy, and warm) until I get the temps up to the mid 60's where I will hold it for 2-3 days for a diacetyl rest. Seems to produce a pretty clean lager in a shorter period of time, at least IME.

[Daddy Biers]

The last few years I have subscribed to Tasty's fermentation schedule for lagers (more or less). Basically I pitch a healthy starter (slurry only) into 48F wort and aerate heavily. Depending on the gravity I typically let it stay between 48-50F for about 5-7 days and as the krausen starts to drop back in to the beer, I gradually raise the temps 3-4 degrees F (or so) every couple days (to keep the yeast active, happy, and warm) until I get the temps up to the mid 60's where I will hold it for 2-3 days for a diacetyl rest. Seems to produce a pretty clean lager in a shorter period of time, at least IME.

The man speaking pure knowledge!!!!!! He has helped me with me first Pilsner and it's going GREAT!!!!!

Daddy Biers!

[Klickitat Jim]

Pitching warm to get it started the dropping makes sense only if you are focusing on trying to get your pitched yeast rolling before an infection can take over.

But, where does lacto, pedio, aceto like to be? Warm right? Plus, the major portion of flavors come in the first 48 or so hours. So starting at 68 is counterintuitive to fermenting a lager.

My method is simple. Pitch at 48° or less. Set temp control to 50°. In about 3 or 4 days when I notice airlock activity slowing down I start a one degree per day increase till I get to 60. Then I take a gravity reading. When I'm within 4 or 5 points of expected FG I set my temp at 68°. At terminal gravity I drop it to 32° and hold for a week. Keg, carb, lager, tap

[brewinhard]

You gotta love turnin' those lagers around quickly! I have found that they do improve in flavor and mouthfeel with some extended lagering (i.e. 4 wks or so). But it is nice to ferment them out quickly so they don't tie up the fermentation chamber for too long.

[Charlie]

Pitch at 48° or less. Set temp control to 50°. In about 3 or 4 days when I notice airlock activity slowing down I start a one degree per day increase till I get to 60. Then I take a gravity reading. When I'm within 4 or 5 points of expected FG I set my temp at 68°. At terminal gravity I drop it to 32° and hold for a week. Keg, carb, lager, tap

That sounds like a plan!

[biertourist]

I agree in general with most of what was said here. Never pitch warm.

BUT you should know that 820 is a strange and pain-in-the-ass lager strain. I have used it almost exclusively for my lager brewing; I LOVE malty oktoberfests and bocks with it and nothing else will do, BUT it is like yeast in slow motion and it is INSANELY slow at taking up diacetyl.

Be ready to take the general schedule / practices of Tasty's and just extend them out for far longer with this yeast strain.

The first time you brew lager, it's like an ale fermentation in slow motion and you can clearly watch the different theoretical phases, but with 820 it's like hitting the 4x slow motion button unless you have a HUGE starter.



DEFINITELY ramp your way up to diacetyl rest temps, but keep checking the gravity and start it once you have only 3 points left to your estimated FG; it might take more than 5-7 days for this strain if you didn't pitch a LOT of yeast. Then do a "Diacetyl force test" before you finish your D-rest or the dreaded diacetyl will show up once you transfer to keg and chill. -If this DOES happen, make another starter with the yeast and pitch a "krausen beer" after warming the keg back up to D-rest temps.

People talk about the Fuller's strain being diacetyl-prone and the Budwar/Czechvar Czech Lager strain, but, IMHO, nothing is as slow as taking up diacetyl as 820.


Alternatively, add 5 drops of this: http://www.hopinhomebrew.com/products/v ... biomat-dar to your fermenter at the same time you pitch your yeast. If you don't want your fermenter tied up for 4-8 weeks, BioMat DAR is cheap "WLP 820 insurance".


Adam