How long does it take yeast to clean up off-flavors?

[jakehoodlum]

Brewing a blonde ale w/ nottingham yeast - Krausen took 24 hrs to form and dissipated in 2 days, so now I am trying to figure out how long to leave in the primary to clean up diacetyl, acetaldehyde, etc. Any thoughts? I am fermenting at 67F in a ferment chamber

 

[EJay]

Brewing a blonde ale w/ nottingham yeast - Krausen took 24 hrs to form and dissipated in 2 days, so now I am trying to figure out how long to leave in the primary to clean up diacetyl, acetaldehyde, etc. Any thoughts? I am fermenting at 67F in a ferment chamber

You'll get a lot of opinions, but I like to go 3 weeks in primary for normal gravity beers.

 

[HB_in_Subic]

You'll get a lot of opinions, but I like to go 3 weeks in primary for normal gravity beers.

I do the same. My ales usually stop bubbling within 4 days. I have noticed a better tasting brew since I started doing this.

 

[PrinceOfThePoint]

I think you'll get lots of anecdotal evidence here about how most beers given ample time to sit and "clean up" will tend to taste cleaner and better. That is also what I have found in my experience. However, if the gravity isn't still dropping you can prepare it for drinking at any time. It might taste a slightly different in it's slightly immature state but it'll still be good beer. So it's up to you

 

[Yooper]

The 'clean up' phase of the yeast, where yeast are still active once fermentation slows and finishes, is about 24 hours. That's when they digest their own waste products like diacetyl. Acetaldehyde is a precursor to alcohol, and usually that cleans up by the end of fermentation but if not if it's oxidized. That may fade with some time, but it's not a function of the yeast by that time.

Generally, the 'clean up' that is talked about here lasts from just before FG is reached to about a day after. The beer will clear after that, and sometimes the yeast flocculating out is what some homebrewers will mistake for part of that "clean up" process.

 

[ChelisHubby]

Yooper most normal gravity beers are done fermentating in 8 to 10 days so the yeast is done cleaning up say 2 days later? So if I understand you any changes after the yeast is done is just conditioning or aging or the yeast flocculating

. I am guessing a normal ale being 1.060 gravity more or less.

 

[jakehoodlum]

You'll get a lot of opinions, but I like to go 3 weeks in primary for normal gravity beers.

From what I have read on this thread, if most processes are done around 14 days, what will leaving it in the primary for 3 weeks do better? I am brewing a 1.044 OG blonde ale and obviously getting antsy to drink it! Would going ahead and kegging it at the 14 day mark be any different than the 21 day mark?

I might get crap for saying this, but I am hesitant to check my FG readings frequently to make sure its at a constant gravity because I am trying really hard not to take off the airlock and risk oxidation or contaminating off-flavors. I am fairly confident the beer will be fully attenuated by then.

 

[Talgrath]

3 weeks is, more or less, "I'm sure it's done", additionally three weeks means additional time for the beer to clear as the dead yeast and other debris fall to the bottom. Strictly speaking, three weeks is not necessary; I usually do two (possibly with one more week for dry-hopping or other additions).

As for your original question, as Yooper said, it takes about 24 hours for the yeast to "clean up"; but this can vary slightly between yeasts I've found. Usually American yeast strains do their magic in 24 or less, but I've found that Belgian yeasts generally take about two days (though they're usually a little cloudier anyway); but this is all anecdotal. There's not a single right answer in part because other factors are likely in play here, temperature, yeast nutrients available in your wort, oxygenation and other things all play a factor in how quickly your yeast does its work. In commercial setups (even for craft brewers) you can often turn a beer around in a week or so because you can dial things in exactly for each beer, but home brewing is hampered a bit by the fact that we don't have pro setups.

 

[Yooper]

From what I have read on this thread, if most processes are done around 14 days, what will leaving it in the primary for 3 weeks do better? I am brewing a 1.044 OG blonde ale and obviously getting antsy to drink it! Would going ahead and kegging it at the 14 day mark be any different than the 21 day mark?

I might get crap for saying this, but I am hesitant to check my FG readings frequently to make sure its at a constant gravity because I am trying really hard not to take off the airlock and risk oxidation or contaminating off-flavors. I am fairly confident the beer will be fully attenuated by then.

It depends on what you mean by "better". A 1.044 OG ale should be done fermenting in just a couple days. I'd normally wait at least three days after FG is reached, or when the beer is clear (or clearing) before packaging. Others like the flavors imparted by a longer contact time with the trub. I listened to a podcast by Basic Brewing about this very thing- the same beer with a primary only, a primary/secondary, and a longer time on the yeast cake. The results were pretty evenly divided, with preferences for each.

My preference is less time on the trub, but still not a super short time (about 7-10 days total assuming a well made beer). You may prefer the flavor of a shorter or longer time on the trub. I can't tell you what your preference is.

 

[tagz]

If you pitch the right amount of yeast and control temps most ales are done fermenting after 3-4 days. I usually give it 2-3 days after the krausen drops to clean up, then cold crash for a couple more to knock the rest of the yeast out. I almost always package around 10 days.

I should mention that I brew < 1.060. But for me, fresher is better!

 

[philosofool]

Yeah, I am in the "as long as you do it right from the start, "clean up is not a long process" camp. I let my beers go until they're fermentated, wait two days, and then cold crash or transfer (for aging beers, lagers, etc.)--of course, I sometimes take awhile to get around to that, espcially if it's a barleywine that I can't be in any rush for. I cold condition most beers for at least four days; lagers get a month or more. Cold conditioning is really just about clarity, not flavor, except when it's long. That long conditioning is not a yeast activity: it's other chemical changes that happen in all beers as they age and are, in my opinion, necessary in true lagers.

I think fermentation control up front is important.

 

[EJay]

From what I have read on this thread, if most processes are done around 14 days, what will leaving it in the primary for 3 weeks do better? I am brewing a 1.044 OG blonde ale and obviously getting antsy to drink it! Would going ahead and kegging it at the 14 day mark be any different than the 21 day mark?

I might get crap for saying this, but I am hesitant to check my FG readings frequently to make sure its at a constant gravity because I am trying really hard not to take off the airlock and risk oxidation or contaminating off-flavors. I am fairly confident the beer will be fully attenuated by then.

MY reasoning for usually going 3 weeks in primary is this:

• My pipeline is usually pretty full, so I'm in no rush.
• I have a bunch of fermenters, so I'm in no rush to vacate one (I do 2.5G batches and I use Brewdemon and Mr Beer LBKs).
• I'm lazy, and don't want to risk contamination, so I don't often check gravity except AT 3 weeks to just make sure the FG is near predicted (and not, say, stuck 15 points too high).
• The old rule of thumb used to be 1-2-3 (1 in primary, 2 secondary, 3 in bottle). Its pretty well-established these days I think that secondaries are usually unnecessary, but the total of 3 weeks in fermenters still works for me.
• MY beers just seem to taste better when I let them primary for 3.

YMMV of course, and I've certainly done much sooner or later when I've been antsy. In fact, I've got a Yooper Pale Ale in the fermenter right now that I think has been there a month.