Logistics of warm lager fermentation for homebrewers
Posted: Fri Jun 10, 2016 8:56 am
I just saw a thread on FB about Mike's lager talk...and the warm lager fermentation schedule. Not zeroing in on Mike, it just prompted me to post some thoughts and a question.
Since switching to brewing lodo, I feel like I have been looking at fermentation more as a tool to preserve flavor and manage oxygen throughout the process, not only 'turn sugar into alcohol'. Using a cold fermentation and spunden I now have far better control over managing flavor development and oxidation protection as the beer moves through the process.
So in the context of oxygen management (not to mention smoothness of flavor and fermentation character) it seems to me a warmer fermentation schedule makes less sense for a homebrewer. For a big brewery that can dial in fermentation pressure to suppress esters, and can do excellent closed transfers via gas purging, I'm sure it works (as it is commonly used). But the schedule seems to neglect unique issues homebrewers have where the cold ferm/spunden makes a lot of sense.
If you ferment starting warmish (10C), then keep going up, at the end of fermentation you are left with a warm beer at FG in a fermenter (carboy or similar for a typical homebrewer). How do you transfer it without introducing oxygen and oxidizing the beer? Seems like the beer is totally unprotected and has no defenses (including benefits from sulfur). And in my experience, I've burned much of the flavor out of the beer at those temps. Never mind preserving the malt flavor of a lodo mash and tuned boil.
And if you crash (or even slow) cool it, pressure differential changes and for many folks the cooling sucks air into the fermenter.
If you have appropriate equipment to manage fermenting under pressure, purge lines and assure no oxygen ingress, it may work, but I would think that is more work to design for vs cold fermentation in the first place.
I'm on my 4th cold/spunden fermentation now so will post more thoughts and experiences as I have them, but using a 6.5g keg, fermenting in my lagering freezer with heater and Brew Pi temp controls, I can chill to 7C, pitch and manage temps quite accurately up and down. These most recent beers never warm past 10C (now staying lower since I can pre-chill colder), so I can slowly drop temps for secondary and take a nice gradual ramp down. I have 1 beer that finished up and is now at freezer temps, one that is in secondary and holding, and one that is actively fermenting from brewing earlier this week. And I freed up an entire freezer.
What are your thoughts and experiences with the different fermentation temp schedules?
Since switching to brewing lodo, I feel like I have been looking at fermentation more as a tool to preserve flavor and manage oxygen throughout the process, not only 'turn sugar into alcohol'. Using a cold fermentation and spunden I now have far better control over managing flavor development and oxidation protection as the beer moves through the process.
So in the context of oxygen management (not to mention smoothness of flavor and fermentation character) it seems to me a warmer fermentation schedule makes less sense for a homebrewer. For a big brewery that can dial in fermentation pressure to suppress esters, and can do excellent closed transfers via gas purging, I'm sure it works (as it is commonly used). But the schedule seems to neglect unique issues homebrewers have where the cold ferm/spunden makes a lot of sense.
If you ferment starting warmish (10C), then keep going up, at the end of fermentation you are left with a warm beer at FG in a fermenter (carboy or similar for a typical homebrewer). How do you transfer it without introducing oxygen and oxidizing the beer? Seems like the beer is totally unprotected and has no defenses (including benefits from sulfur). And in my experience, I've burned much of the flavor out of the beer at those temps. Never mind preserving the malt flavor of a lodo mash and tuned boil.
And if you crash (or even slow) cool it, pressure differential changes and for many folks the cooling sucks air into the fermenter.
If you have appropriate equipment to manage fermenting under pressure, purge lines and assure no oxygen ingress, it may work, but I would think that is more work to design for vs cold fermentation in the first place.
I'm on my 4th cold/spunden fermentation now so will post more thoughts and experiences as I have them, but using a 6.5g keg, fermenting in my lagering freezer with heater and Brew Pi temp controls, I can chill to 7C, pitch and manage temps quite accurately up and down. These most recent beers never warm past 10C (now staying lower since I can pre-chill colder), so I can slowly drop temps for secondary and take a nice gradual ramp down. I have 1 beer that finished up and is now at freezer temps, one that is in secondary and holding, and one that is actively fermenting from brewing earlier this week. And I freed up an entire freezer.
What are your thoughts and experiences with the different fermentation temp schedules?