Fermentation Process for a Lager

[Malik506]

I am brewing my first lager (1 gallon batch) and I've completed 2 weeks at 55 degrees and 3 days at room temp for the diacetyl rest. I've hit my final gravity. Last night I returned it to the fridge and lowered the temp to 35 degrees. I am now realizing that some recommend lowering the temp gradually after the diacetyl rest - like 5 degrees a day until you get to the target 35 degrees. What is the purpose of this and how big an issue is it that I went straight to 35 degrees??

Also, since I am only making a 1 gallon batch, is 30 days enough time at 35 degrees? My recipe says 60 days, but its for a 5 gallon batch. I don't know if a smaller volume requires less lagering time? 2 months is a lot of time to wait for a gallon of beer!!

Thanks in advance for the help and advise. I have learned so much from this community.
Mark

 

[GuldTuborg]

This seems to be one of those perennial debates. Suffice to say that it's not incorrect to do it either way, but some people feel strongly or claim to have compelling evidence that one way is better than the other. I'll let you decide if you want to go down that rabbit hole.

As to the lagering time, I don't have a definitive answer based on science, but my gut tells me there's no real impact volume should have. If you had to double your lagering time every time you went up 4x in volume (1 gallon to 5 gallons, taking this example), produicers of American light lagers would be lagering for decades. But they don't, of course. The real secret here is to get a pipeline going. Once your initial batch starts lagering, brew another!

 

[ba-brewer]

And 12oz bottles in a week.

My 3gal batches take as much lager time as my 5gal batches.

How do you plan to package your beer?

If you plan to bottle, might be better to do that now verse later when your yeast had all fallen out.

I dont crash my lagers(or ales), they go in the keg once the diacetyl rest is over and crash/carb while conditioning.

 

[McKnuckle]

The better approach with bottling would be to do a brief, "normal" cold crash in the fermenter, and then bottle. Carbonate warm for 3 weeks, and only after that would you lager in the bottles for the duration.

If you first lager in the fermenter for weeks, you'll possibly have a more complicated time bottling. Not definitely, but it at least becomes a concern.

About the timing of the temperature drop; the reason for doing that slowly was because in traditional lagering, it was important to prevent the residual yeast population from being shocked and going completely dormant. It was expected that they would continue to slowly metabolize and clean up the beer's flavor over the long haul. By dropping temp slowly, apparently that could be achieved.

 

[Malik506]

Thanks for the input guys. Sounds like good news and bad news. Good news that going straight to 35 degrees doesn’t sound like a problem. Bad news that it sounds like I’m still looking at 60 days of lagering! I will definitely have to get the pipeline going...

Not bottling. I have a 1 gallon “keg” with C02 and regulator. after the diacetyl rest I siphoned into a secondary carboy for lagering. after 60 days I’ll move to the keg and force carbonate. In retrospect I guess I could have just lagered in the keg and saved a step. Still learning here...

 

[McKnuckle]

^ your last sentence, exactly. Kegs are the perfect lagering vessel. After 2 weeks, it's (mostly) fully carbonated, then you can sample periodically - just a little at a time - every few days.

 

[Vale71]

As to the lagering time, I don't have a definitive answer based on science, but my gut tells me there's no real impact volume should have. If you had to double your lagering time every time you went up 4x in volume (1 gallon to 5 gallons, taking this example), produicers of American light lagers would be lagering for decades. But they don't, of course. The real secret here is to get a pipeline going. Once your initial batch starts lagering, brew another!

Science tells us that at least as far as the beer clearing naturally by sedimentation volume, or better yet depth of the liquid, does have a definite impact. Since suspended particles need to travel up to the whole depth to finally make it to the bottom the time it takes for the beer to clear sufficiently scales linearly with size and geometry of the vessel. That's the reason why traditionally maturation tanks where laid on their side and not standing up, to make the beer clear faster by natural sedimentation. This is still the case in very old breweries in Europe. At the homebrew level you'd notice a difference between 5 gal and 2.5 gal cornys for example, with the former being exactly half as tall as the latter and therefore clearing about twice as fast.

Producers of American light lager nowadays ferment warm under pressure, condition warm and then centrifuge and filter the heck out of their product so their process and their timings cannot be meaningfully compared to ours .

 

[Sunfire96]

Something to consider for your next lager...a 1 gallon batch probably finished fermenting after 2 weeks (even with lager yeast), so it's possible that the yeast weren't able to complete a diacetyl rest. Next time, try to bump up your temperature after about 90% of fermentation is complete, but not 100% finished. Assuming that you can check your SG in a safe way

As far as lowering your temp to 35 quickly, I think the speed mostly affects how much suck back/oxidation occurs by a quick temp change. If you've found a way to avoid that and drop fast, then that's awesome whatever works for you! Have you seen the brulosophy quick lagering method? That helped me understand the mechanics of lagering (even with small batches). Cheers!

 

[charlesbrewer]

I personally categorize those that no one have definite proof for benefit as myth or at least not a factor for 5-10 gal batches. Do once or twice and be the judge yourself. If you think its better then do it, otherwise let it go.

As long as you lager at 35F of so for up to 4 weeks you'll really see the difference.

 

[GuldTuborg]

Science tells us that at least as far as the beer clearing naturally by sedimentation volume, or better yet depth of the liquid, does have a definite impact. Since suspended particles need to travel up to the whole depth to finally make it to the bottom the time it takes for the beer to clear sufficiently scales linearly with size and geometry of the vessel. That's the reason why traditionally maturation tanks where laid on their side and not standing up, to make the beer clear faster by natural sedimentation. This is still the case in very old breweries in Europe. At the homebrew level you'd notice a difference between 5 gal and 2.5 gal cornys for example, with the former being exactly half as tall as the latter and therefore clearing about twice as fast.

Producers of American light lager nowadays ferment warm under pressure, condition warm and then centrifuge and filter the heck out of their product so their process and their timings cannot be meaningfully compared to ours .

While I'm sure there is *some* impact, I have difficulty seeing that the need for time scales linearly with volume or height. At any rate, what I'm talking about here is not the duration of time it takes for a particle to travel top to bottom (that doesn't seem controversial here) but rather the "recommended" lagering times.

 

[Tobor_8thMan]

[QUOTE="McKnuckle, post: 9020582, member: 183976"
If you first lager in the fermenter for weeks, you'll possibly have a more complicated time bottling. Not definitely, but it at least becomes a concern.[/QUOTE]

I believe @McKnuckle means there will be CO2 in the beer. I only post as OP writes this is their first lager and I am trying to help.

 

[VikeMan]

If you first lager in the fermenter for weeks, you'll possibly have a more complicated time bottling. Not definitely, but it at least becomes a concern.

I believe @McKnuckle means there will be CO2 in the beer. I only post as OP writes this is their first lager and I am trying to help.

I'm pretty sure he meant the yeast might settle out so much that carbonating in the bottle might be hindered. That's usually not an issue, but it can be sometimes.

 

[McKnuckle]

^Indeed. Not usually a fatal problem, but if you have much less yeast in the bottles, carbonation will take longer - possibly a lot longer. And if you are impatient and/or inexperienced with bottling, you may read about typical carbonation times here on HBT, and then wonder why it didn't work for you. Prompting another thread, of course.

 

[Beermeister32]

There are other taste profile improvements that occur with lagering in addition to clarifying the beer. The taste improves as it matures.

If you have lagered your beer and you are worried there is no yeast left in suspension for bottling, take a little yeast in small mason jar and use a new and sanitized eye dropper to add a tiny squirt into the beer bottle prior to capping. Yeast type is not as important at this stage, don't feel the need to use the same type, even mixing up a little US-05 ale yeast will work. Don't re-use the droppers for your eyes, keep them with your beer things!

 

[Brooothru]

There are other taste profile improvements that occur with lagering in addition to clarifying the beer. The taste improves as it matures.

If you have lagered your beer and you are worried there is no yeast left in suspension for bottling, take a little yeast in small mason jar and use a new and sanitized eye dropper to add a tiny squirt into the beer bottle prior to capping. Yeast type is not as important at this stage, don't feel the need to use the same type, even mixing up a little US-05 ale yeast will work. Don't re-use the droppers for your eyes, keep them with your beer things!

Better yet, make a mini-starter, wait for fermentation to start, then introduce a millimeter or so into each bottle just before capping and conditioning. Voila! Instant krausening. Just be VERY careful to be at or near terminal gravity to avoid bottle bombs.

Brooo Brother

 

[Malik506]

Thanks for the great feedback! I just read brulosophy’s article on quick layering method and it is really helpful in understanding the overall process. I’ll probably give it 30 days in the secondary then rack to keg, carbonate and taste test to see where I’m at to determine if I need the full 60 days.