How long can a beer stay in primary?

5 years is way too long

More serious answer, it depends, but 4 - 6 weeks should not be a big problem for most beers. What kind of beer are you asking about? Where would it be kept, i.e. basement with stable temps or a sunny porch with lots of temp fluctuations?

 

The answer is "so long that lots of yeast start to burst (autolysis) or the trub starts turning into soap." When those things start would depend on lot of factors that you really can't quantify. A lot of people would say that 4 weeks is generally safe, and I agree. Beyond that is when I would personally start to think about getting nervous.

Why do you want to leave it in the primary for a long time? And why do you want to transfer it to a secondary after that? Are you going to rack onto fruit or some other special ingredient in the secondary?

 

@Peter_Wolfe posted on this topic in a prior thread:

"You'll start seeing low level autolysis after about 3 weeks, IF 1) you started with healthy yeast, and 2) the fermentation temp was kept low (68F or under the whole time). If you start with unhealthy yeast or heat stress it, it'll happen sooner. It takes 6-8 weeks to start seeing wholesale autolysis that gives off the soy sauce flavor if you never transfer off of primary. In a big dark beers (especially stouts), this flavor is pretty effectively masked until it gets really bad, but it shows up like crazy in pale ales.

As they autolyze, the yeast release enzymes, lipids, and metal cations that all have a negative effect on flavor."

Cheers!

 

@Peter_Wolfe were you referring to homebrew or to commercial brewing in the quote above? My understanding is that one important factor in yeast autolysis is pressure, which is much lower in a bucket/carboy conical than in a large, multi-barrel conical.

I can add that I have had some slowly fermenting saisons in primary for about 6 weeks without any hint of autolysis derived off flavors.

 

OP, you mentioned a secondary, so that invites a comment. I don't know your reason for saying that, but if your recipe instructions is the reason, I'll suggest against doing it. Using a secondary fermentor is only necessary if you are going to bulk age a beer, or if you want to allow a beer to sit on fruit or oak for a period of time before packaging. Transferring froma primary to a secondary to your bottling bucket or keg adds one unnecessary transfer into the picture during which oxygenation of the beer can occur.

 

I've gone 6-8 weeks in a bucket, still with good results. After you hit FG and 2 weeks later, you should be moving your beer to package or secondary. Life gets in the way sometimes.

 

THIS. autolysis is a non-issue for homebrewers making 5 gallon batches.

 

I don't think it's a non issue, because people have experienced it. But I do think it's not a very common problem in homebrew.

 

This seems like a much shorter time than experience suggests. I don't necessarily doubt that it might be happening that early, but I question the impact on beer at this stage. I wonder whether in the earliest stages of autolysis, there may be active yeast cells that are taking up or breaking down the compounds released by the dying cells, so that autolysis goes unnoticed for some time, until a majority of cells die. I'm sure it is well studied. I don't know the answer.

 

uncommon indeed. i have never heard of a single verified instance of autolysis occuring in a small-batch homebrew. i myself have left beers in primary for months with no ill-effects

 

Peter, I do not have much personal experience to provide here. I typically package my ales with less than 3 weeks of primary; for moderate gravity ales where I do not dry hop I typically package after 1 week of primary time.

I know that a fair number of BAs post that they keep the beer in the primary for something like 3 weeks but frankly I do not see the need/reason for such a long time in the primary.

Maybe now would be a good time to repeat what I have posted numerous times before: Homebrew the beers you like and brew them the way you like.

Cheers!

Jack

 

I second this.

The following is only a single example, so it doesn't prove anything. I'll describe it anyway. I made a beer with my brother one Thanksgiving. The following July we kegged it from the primary. It was awesome.

 

I typically package at the 2 week mark for ales, and the three or four week mark for lagers (since I am only averaging about 1 lager per year, I'm not sure I have established a definitive standard yet). But I have no qualms about going 2-3 weeks longer if I am struggling to get my act together. I never have tasted anything like autolysis; I worry more about oxidation.

 

As Peter Wolfe posted it takes a bit longer for very noticeable flavors to be noticed: "It takes 6-8 weeks to start seeing wholesale autolysis that gives off the soy sauce flavor if you never transfer off of primary."

In the shorter timeframe the presence of autolysis will be less but apparently there nonetheless: "As they autolyze, the yeast release enzymes, lipids, and metal cations that all have a negative effect on flavor."

Again, I can't provide personal feedback since I package my ales in less than 3 weeks.

You should continue to do what you are doing if you are satisfied with your practice.

Cheers!

 

Righto. No one can argue with that.

 

Homebrewing. It'll happen way faster in large commercial fermenters (both because of hydrostatic pressure and because most homebrewers are using low generation yeast). I should note though that you can have a fair amount of autolysis occur before you start seeing off-flavors from it. The easiest way to track it analytically is to look at iron - yeast will sequester iron intracellularly and then release it when they lyse. If you look at iron levels in the beer you'll see it steady for weeks and then slowly start to rise as yeast die off. This precedes all other more obvious indications.

The initial autolysis will be handled by other living yeast - they'll (somewhat) reabsorb the iron, acetaldehyde, etc. that the first round of dead yeast spill out into your beer. It's similar to pH buffering capacity in a sense. However, even a small amount of lysis will have a negative impact on your beer - cytoplasm proteases (not bound to membrane, in other words) will go to work on residual proteins in the beer and have a significant impact on foam stability/retention. The iron/copper that isn't readsorbed will increase the oxidation rate of the beer exponentially.

What I'm saying is there's negative impacts long before you get to the point where you can "taste" autolysis. There's nothing good to be gained from leaving beer on primary too long, especially when it's so easily remedied simply by dumping the cone or transferring to a new bucket/carboy.