Step 1: Primary Fermentation
Chill wort to pitching temp of 48°-53°F (9°-12°C), pitch adequately sized starter (decanted), set regulator to initial fermentation temp between 50°-55°F (10°-13°C), and leave the beer to ferment until it is at least 50% attenuated. I’ve found the time this takes is dependent on 2 primary factors:
- Original Gravity: a 1.080 Doppelbock is going to take longer to reach 50% attenuation than a 1.048 Helles.
- Yeast Type: in my experience, rehydrated dry lager yeasts take 12-36 hours longer to show signs of active fermentation compared to liquid yeasts built up in starters or even slurry harvested from a prior batch.
I originally advised leaving the fermenting beer at primary temp for 5 days assuming folks were checking SG prior to making temp changes. This was a mistake on my part. While it is possible even high OG beers will reach 50% attenuation in this amount of time, I’ve heard from a couple folks who experience differently. As such, here are my new better-safe-than-sorry recommendations:
OG OF WORT YEAST TYPE APPROXIMATE PRIMARY TIME
≤ 1.060 OG Liquid 4-7 days
≤ 1.060 OG Dry 5-8 days
≥ 1.061 Liquid 6-10 days
≥ 1.061 Dry 7-14 days
Another factor worth considering is your preferred primary fermentation temperature, as yeast is going to work a bit faster at 54°F (12°C) compared to 48°F/ (9°C). The original 5 day recommendation will likely hold true for most folks, as it has for me, I just want to emphasize the importance of taking SG measurements prior to making temp changes.
Step 2: The Ramp Up
Once 50% attenuation is reached, remove the probe from the side of the fermentor so it measures ambient temp in the chamber and start bumping the regulator up 5°F every 12 hours until it reaches 65°-68°F (18°-20°C). Allow the beer to remain at this temp until fermentation is complete and the yeast have cleaned-up after themselves, which can take anywhere from 4 to 10 days.
Alternate Option
Keep the temp probe attached to the fermentor and forgo the incremental temperature increases but immediately setting your regulator to 65°-68°F (18°-20°C). While I still prefer the more gentle approach to temp increases, I’ve heard from many people have had great success using this slightly less time-consuming approach.
Step 3: The Ramp Down
When FG is stable and no diacetyl or acetaldehyde is detected in the beer, begin ramping the temp down in 5°-8°F increments every 12 hours or so until it reaches 30°-32°F (-1°-0°C). Allow the beer to remain at this temp for 3-5 days, during which it will begin to drop clear.
Alternate Option 1
Setting the regulator to 30°-32°F (-1°-0°C) without gradually stepping the temp down will shave 2-3 days off of the entire process. Many brewers have done this with positive results, myself included, though I still tend to prefer the original method if only to reduce the amount of airlock fluid that gets sucked into the beer as it crashes.
Alternate Option 2
If super bright beer is something you pine for, as I do, and you’re okay with putting animal products in your beer, as I am, consider adding gelatin once the temp of the beer has reached 50°F (10°C). In my experience, this has significantly decreased the amount of time required for the beer to clear to commercial levels, I usually end up kegging 24-48 hours after adding the gelatin.
Step 4: Packaging & Storage
Once the beer is clear, it’s ready to be packaged, the process of which is obviously different depending on whether one uses kegs or bottles. Yes, bottle conditioning is absolutely possible with this method.
For Those Who Keg…
Simply transfer the cold and clear beer to your keg, place it in your keezer on gas, and leave it for 3+ days before enjoying! Using my typical kegging/carbonation method in conjunction with gelatin, I’ve found the beer is usually ready for consumption after about 5 days of “lagering” in my keezer, while others swear their beers peak after 2 weeks or so of cold storage. This is likely an issue of subjective preference mixed with a sprinkle of confirmation bias, but regardless, do what you works best for you!
