Membership questions? Log in issues? Email info@brewersassociation.org

Author Topic: Length of time between FG and kegging/bottling?  (Read 3017 times)

Offline trapae

  • Brewer
  • ****
  • Posts: 402
Length of time between FG and kegging/bottling?
« on: October 19, 2021, 08:26:06 am »
So I just got a tilt hydrometer.
My typical schedule for ale is/was:
After brew day I ferment at around 64° temperature controlled for about a week..
Then I raise the temperature to around 70° and leave it for about 2 1/2 weeks to clear out unwanted “stuff“.
Cold Crash three days and then keg. Take a final gravity prior to kegging.
So about four weeks from brew day to keg.

Typically not too worried about time and just want a good beer. But now with the tilt, I just brewed on Saturday and 48 hours later I am at final gravity. Going to raise the temperature today to 70° for a ale Diacetyl rest. Now I’m rethinking my four week schedule and wondering if I’ve been wasting a ton of time this whole last decade.
-so I was wondering what everyone else does and how much time people leave the beer in the fermenter after final gravity is established prior to bottling/Kegging? Thanks.
I am a great believer in luck, and I find the harder I work, the more I have of it.

Offline BrewBama

  • Official Poobah of No Life. (I Got Ban Hammered by Drew)
  • *********
  • Posts: 6055
Length of time between FG and kegging/bottling?
« Reply #1 on: October 19, 2021, 08:39:53 am »
As soon as I hit terminal gravity (~4-6 days for Ales), I closed transfer to keg and cold crash/condition/lager/carbonate (simultaneously). I move the keg to serving when I need it (usually a cpl weeks to one month).

I don’t like leaving the beer in the fermenter after terminal gravity because I don’t want to pick up O2. In my opinion, when it’s done it’s done.
« Last Edit: October 19, 2021, 08:48:07 am by BrewBama »

Offline RC

  • Brewmaster
  • *****
  • Posts: 669
Re: Length of time between FG and kegging/bottling?
« Reply #2 on: October 19, 2021, 09:19:42 am »
By the time the beer has reached a stable final gravity, all the unwanted byproducts should be cleaned up (with a caveat; more below), and it's ready for packaging. But it won't hurt to let the beer sit around for a few extra days, or even weeks. So while your schedule for an ale is longer than it needs to be, you haven't been doing any harm.

My ale schedule for grain-to-glass is typically 2-3 weeks, with dry hopped beers on the longer side. I could shorten this but I am in no rush. And to take FG, I have to open the fermenter, which introduces oxygen. And so I generally do not monitor FG before kegging. With me, waiting a little longer is just insurance to guarantee full attenuation and cleanup. I use plastic fermenters and have never had oxidation issues, even after 6 months in the carboy.

The caveat is if you have too fast a fermentation--and 48 hrs to reach FG strikes me as too fast. You don't want a slow fermentation but you also don't want too fast a fermentation. With rapid fermentations, such as what you get when overpitching by a lot, the yeast might go dormant before they have a chance to clean up. Residual acetaldehyde is common in this situation, more so than diacetyl.

Fermentation is indeed done when it's done, and usually cleanup is at the same time, but not always.

I suggest tasting that beer before cold-crashing and also do a forced VDK test to ensure that at least the diacetyl precursor isn't present.

Offline Megary

  • Senior Brewmaster
  • ******
  • Posts: 1129
Re: Length of time between FG and kegging/bottling?
« Reply #3 on: October 19, 2021, 09:38:40 am »
I agree with the "when its done its done" sentiment, but I'm not always ready to keg when that bell goes off.  Still, for ales, I've never gone longer than 2 weeks in the fermenter and sometimes only one for those particular yeasts that are quick to retire (Windsor, London...).

Offline Drewch

  • Brewmaster
  • *****
  • Posts: 582
  • Just this guy, you know?
Re: Length of time between FG and kegging/bottling?
« Reply #4 on: October 19, 2021, 10:05:10 am »
...for ales, I've never gone longer than 2 weeks in the fermenter...

I don't know where this falls on the ale vs. lager spectrum, but I had a batch with Lachancea (vs. Sacc C. or Sacc P.) that kept dropping a point or so every two days for a month.
The Other Drew

Home fermentations since 2019.

Member at large of the Central Alabama Brewers Society and the League of Drews.

Offline denny

  • Administrator
  • Retired with too much time on my hands
  • *****
  • Posts: 27093
  • Noti OR [1991.4, 287.6deg] AR
    • Dennybrew
Re: Length of time between FG and kegging/bottling?
« Reply #5 on: October 19, 2021, 10:08:47 am »
Here's some info from John Palmer that may have a bit of relevance...

100-150 years ago, fermentation was open, followed by maturation in a wooden cask. The beer
was prone to contamination. This could be mitigated by heavy hopping and long warm
maturation to wait for the bitterness to die down, or by long cold maturation (lagering) to use
temperature to keep the contamination down.
Yeast have 3 phases in their life cycle: Adaptation, High Growth, and Stationary. (See Yeast by
CW and Jamil) They do not have a maturation phase where they clean up byproducts. Adaptation
phase is where they take in oxygen and build sterols and other lipids, assess the sugar
composition and build enzymes, etc. Once those activities are done, they start the High Growth
Phase, eating and reproducing. The number of cell divisions is limited by their lipid reserves they
made during Adaptation. These reserves are shared with each daughter cell. When those lipid
reserves are exhausted, the cell stops reproducing. In addition, when those reserves are
exhausted, the cell is old and cannot eat or excrete waste efficiently across it’s cell membrane. A
yeast cell typically can reproduce about 4 times during a typical fermentation, after that it is old
and tired and tends to enter Stationary phase where it shuts down most of its metabolism and
flocculates, waiting for the next batch of aerated wort. Stationary phase is essentially an
inactivity phase, resting on the bottom.
Like I said, no conditioning phase as far as the yeast are concerned. Byproducts can be consumed
at any point during the high growth phase, but they are a lower energy source than sugar, so
guess what? Byproducts are not a biological priority. The brewer therefore needs to plan his
pitching rate and fermentation conditions such that the yeast run out of fermentable wort sugar
before their lipid reserves are exhausted and they go into stationary phase. Now you have a
majority of vigorous yeast that have only undergone 2 reproductions (for example), the sugar is
gone, and they are still hungry, so they turn to acetaldehyde and diacetyl as alternate energy
sources and maturate the beer. You can help this by doing a diacetyl rest by raising the
temperature a few degrees after the first half of fermentation, to keep the yeast active and eating.
Where in the fermentation? after the first half, 2/3 to 3/4, when most of the attenuation has
occured and raising the temperature is not going to cause rampant growth and the off-flavors
associated with it.
Today, we have closed stainless steel tanks which allow us to prevent oxidation, pull the yeast,
and control the temperature. This plus our understanding of the yeast cycle above changes the
way we ferment lagers, so now lager beer fermentation is started cooler to control yeast growth
and allowed or controlled to rise during fermentation to the diacetyl rest, such that ALL of the
fermentation and maturation is complete before the beer is cooled to lagering temperature. The
effect of temperature at this stage is strictly physical, increasing the strength of hydrogen bonds
to coagulate beer haze and help it settle out. The yeast are still susceptible to temperature shock
and lipid excretion, so the cooling to lager temperature 35-38F still has to be slow, i.e. 5F per
day.
Please note that this behavior and fermentation technique is applicable to ALL beers, not just
lager beer.
Life begins at 60.....1.060, that is!

www.dennybrew.com

The best, sharpest, funniest, weirdest and most knowledgable minds in home brewing contribute on the AHA forum. - Alewyfe

"The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts." - Bertrand Russell

Offline ynotbrusum

  • Official Poobah of No Life. (I Got Ban Hammered by Drew)
  • *********
  • Posts: 4882
Re: Length of time between FG and kegging/bottling?
« Reply #6 on: October 19, 2021, 11:25:03 am »
The Tilt is really a wonderful tool.  I don't use it for exact (absolute) final gravity measurement, rather to establish that there is no longer any change occurring with time.  I pressure ferment these days a lot and it seems that the FG with the Tilt is skewed a bit lower under pressure, but as I said, I just wait for no changes in gravity for 2-3 days and then drop the fermenter to cooler temps before racking.  I have had many beers finish in 3-4 days, but usually, there are a few points left after 3 days and those final points may take up to another 3 days to complete.  If I have a beer in the fermenter longer than 8 days, it is an anomaly or I don't have an open keg to transfer into.  I purge all of my kegs during active fermentation and they usually purge out fairly quickly, so I typically have a few that are ready for filling (but sometimes I have to leave a fermented beer in primary for a little while longer than necessary, all without any problems).  That is usually a time to see if there are some low kegs to dump or push into growlers....
« Last Edit: October 19, 2021, 11:26:48 am by ynotbrusum »
Hodge Garage Brewing: "Brew with a glad heart!"

Offline trapae

  • Brewer
  • ****
  • Posts: 402
Re: Length of time between FG and kegging/bottling?
« Reply #7 on: October 20, 2021, 06:34:31 am »
Thanks, seems I’ve been waisting a bit of time.
I am a great believer in luck, and I find the harder I work, the more I have of it.

Offline Kevin

  • Brewmaster
  • *****
  • Posts: 726
  • Great beer. Less work. More fun.
Re: Length of time between FG and kegging/bottling?
« Reply #8 on: October 22, 2021, 07:28:22 am »
I started using Kveik yeast this past summer and my typical procedure was pitch the yeast and four days later its in the keg.
“He was a wise man who invented beer.”
- Plato

Offline Richard

  • Senior Brewmaster
  • ******
  • Posts: 1012
Re: Length of time between FG and kegging/bottling?
« Reply #9 on: October 22, 2021, 11:55:37 am »
The information that Denny provided about yeast is correct, but it omits one detail: not every single yeast cell will change from one phase to another at the same time. That means that the boundaries between the phases are not sharp and well-determined in time but are a bit blurred. Part of the yeast culture may be "finished" while the rest is still working.  I am sure that many of us have experienced yeast that are slow to finish, with gravity dropping a point or so a day for a few days at the end of the main fermentation. That could either be that all the yeast are still working slowly, but I think it is more likely that some are done and there are some that are behind in the process and are still working. I usually give a few extra days after reaching FG just to be sure that all the yeast are finished before I cold crash.
Original Gravity - that would be Newton's

Offline scwells72

  • 1st Kit
  • *
  • Posts: 1
Re: Length of time between FG and kegging/bottling?
« Reply #10 on: October 23, 2021, 02:18:51 pm »
So I just got a tilt hydrometer.
My typical schedule for ale is/was:
After brew day I ferment at around 64° temperature controlled for about a week..
Then I raise the temperature to around 70° and leave it for about 2 1/2 weeks to clear out unwanted “stuff“.
Cold Crash three days and then keg. Take a final gravity prior to kegging.
So about four weeks from brew day to keg.

Typically not too worried about time and just want a good beer. But now with the tilt, I just brewed on Saturday and 48 hours later I am at final gravity. Going to raise the temperature today to 70° for a ale Diacetyl rest. Now I’m rethinking my four week schedule and wondering if I’ve been wasting a ton of time this whole last decade.
-so I was wondering what everyone else does and how much time people leave the beer in the fermenter after final gravity is established prior to bottling/Kegging? Thanks.
I started using Kveik yeast this past summer and my typical procedure was pitch the yeast and four days later its in the keg.
I kk m nary 0 nm

Offline tommymorris

  • Official Poobah of No Life. (I Got Ban Hammered by Drew)
  • *********
  • Posts: 3869
Re: Length of time between FG and kegging/bottling?
« Reply #11 on: October 23, 2021, 02:27:57 pm »
I wait at least 3 days after FG is hit. That ensures FG is actually achieved and allows any clean up; especially diacetyl removal. In practice I often wait longer because I generally only do beer work on the weekend.