How Long Should I Ferment?

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Fenix26

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Hey everyone,

I read a lot of recipe kits declare a fermentation longevity on average of about 2 weeks. But I heard a lot of home brewers like to ferment longer than what is even declared from the recipe, on average a month.

I was just wondering if the extra 2 weeks makes for a better brew, or is this just the ego of the home brewer that we all know and love coming out?

If the recipe is correct, duration wise, why would people let it ferment longer?
If it is better to let ferment longer, why would the recipes disagree? Also, if it is better to let ferment longer at what point would you cease the fermentation process and then start to bottle or leg (type of beer depending)?

Thanks, Brew Force!!!!!
 
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Fenix26

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*Cease fermenting due to degradation of the brew is what I meant per the above
 

day_trippr

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I don't know where you are gathering your statistics or what level of brewers you're citing, but unless there's a defect that needs attenuation via time, there's rarely a good reason to leave an ale on yeast that long. Lagers, maybe.

If I had to guess, 9 out of 10 batches I brew are off the yeast cake ~two weeks from pitching, and that includes dry hopping and a couple of days of cold-crashing...

Cheers!
 

Talgrath

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In essence, there's little reason to let it ferment longer, unless you think something isn't working right or going well. My general rule of thumb on an ale is 2 weeks, sometimes you can do it in as few as 9 days. The only reason to leave the beer on the yeast cake for longer than 2 weeks, beyond some sort of fermentation problem (like a sudden drop in temperature) is maybe to let it clear up a bit more, but I've never noticed a difference in clarity from letting the beer sit longer myself though. If you let the yeast sit longer than a month on the yeast cake the yeast dying off can start to create weird flavors and you may need to add more yeast when you bottle to get proper carbonation. Particularly for an extract kit (I'm assuming this is an extract kit and not an all-grain kit) 2 weeks should be more than enough time, bottle after that, let it sit at least a week in the bottles and then chill and enjoy.
 

RM-MN

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You don't ferment beer, the yeast do. They take exactly as long as they want and you have no control over that.

With that said, ale yeasts usually take less than a week to completely ferment out all the sugars and perhaps another day or 2 to clean up. All time after that is allowing the yeast to flocculate and settle out. At that point it is a question of how much sediment you want in your bottles. I've bottled at day 7 and had a quarter inch of sediment in my bottles. I've waited 9 weeks to bottle and had so little sediment it was hard to see even in a clear bottle. I prefer less sediment so I leave my beers longer now but the difference between 3 weeks and 4 weeks is slight.
 

RM-MN

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In essence, there's little reason to let it ferment longer, unless you think something isn't working right or going well. My general rule of thumb on an ale is 2 weeks, sometimes you can do it in as few as 9 days. The only reason to leave the beer on the yeast cake for longer than 2 weeks, beyond some sort of fermentation problem (like a sudden drop in temperature) is maybe to let it clear up a bit more, but I've never noticed a difference in clarity from letting the beer sit longer myself though. If you let the yeast sit longer than a month on the yeast cake the yeast dying off can start to create weird flavors and you may need to add more yeast when you bottle to get proper carbonation. Particularly for an extract kit (I'm assuming this is an extract kit and not an all-grain kit) 2 weeks should be more than enough time, bottle after that, let it sit at least a week in the bottles and then chill and enjoy.
if you change the time from one month to 6 months I'll believe you but one report I got said that 6 months was not too long. The weird flavors come from autolysis and that rarely happens with the quantities homebrewers work with.
 

Aristotelian

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If you are trying to get it into keg/bottles as quickly as possible, the risk you are taking is that it is still actively fermenting. This could affect your carbonation and explode your bottles (if bottling). If you are bottling, you should take gravity readings and make absolutely sure it is finished whether you are bottling at 2 weeks or 4 weeks.
 

mongoose33

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I'm one of those who tends to leave beer in the primary for up to 4 weeks.

It isn't the fermentation that is occurring after two weeks; it's conditioning. I've kegged beer after two weeks that tasted pretty green, but after a couple weeks on the gas, it smooths right out to what I was looking for.

Someone here had suggested leaving the beer in the primary for four weeks as opposed to conditioning in the keg; I tried it and voila! Very nice beer. So it's what I do.

I have a fermenter of Funky Rye that has been there for 23 days sitting and quietly getting better. It's about time to cold-crash it, fine it, and then keg and carbonate it. I might start crashing it tonite, but since I have a partial keg of it on tap, there's no hurry.

That's the beautiful thing about having a pipeline; I've learned patience!
 

myndflyte

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The best way to be sure is to let gravity readings tell you if it's done. For me, I wait at least 2 weeks, usually 3 weeks, but that is just my personal preference.
 
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Fenix26

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The angle I was most accurately describing would be the conditioning as mentioned earlier.
I just breed a malt extract imperial stout, let it ferment gor 2 weeks before bottling, let it sit for 2 weeks in the bottle, and I couldn't believe it, but I had absolutely no sediment in my bottles.

Considering I didn't let it sit inthe primary for 4 weeks, I'd be pretty interested if I could let it sit in the primary for that long, as long as it doesn't disrupt the quality of the beer.

How true is this though? Does an extra set of weeks usually produce a better quality beer, or at least help with sediment deposit?

Thanks!
 

Yooper

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How true is this though? Does an extra set of weeks usually produce a better quality beer, or at least help with sediment deposit?

Thanks!
No. Age is age, no matter what the vessel is. Beer will age in the fermenter, in the keg, or in the bottle. Temperature plays a huge rule, so if the beer needs to age keep it at room temperature. If you want to keep it the way it is, keep it at fridge temps which will slow down the aging.

If you have a very non-flocculant yeast, perhaps you may get less sediment in the bottles if you wait for a month, but for most people once a beer has been at FG for at least 3 days and starting to clear (or is clear), it won't get "doner" or drop less sediment later.
 

BigFloyd

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What Yooper mentioned is one of the more consistent (and easily done) practices for ales. Simply let it ride 10 days, check gravity. Check it again in 3 days. If it's the same, it's ready for a cold crash or bottling/kegging.
 

psujeeperman02

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To add, I'm on week two of my fermentation. I took a reading and it's damn close to what my recipe calls for. The issue is...I still see little bubbles floating up from the yeast cake to the top of the fermenter. Not many, but there are some. Do you think it's safe to package it up even after it's hit the numbers yet still slightly bubbling?
 

RM-MN

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When your beer is fermenting the yeast excretes lots of CO2 and some of this gets dissolved into the beer. When the fermentation is complete there is more CO2 dissolved than the beer can hold so some of it outgasses and this can continue for some time. How much the beer can hold is dependant on temperature so a priming calculator will ask for the beer temp to decide on how much residual carbonation there is so it can compute the amount of sugar needed to get you to the right amount of carbonation.

The bubbles you see rising from the yeast layer are just the residual CO2 outgassing. Use your hydrometer to determine if any more fermentation is occurring. Two reading a couple days apart that match says the the fermentation is done and you can then bottle.
 

ncbrewer

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Since I bottle, I take two SG readings two days apart to be sure fermentation is finished - bottle on the day of the second reading. But I also like to minimize the exposure to the air (not everyone agrees with this). So I go with three weeks in the fermenter. After three weeks it's always been finished (as indicated by stable gravity), so I don't have to open and sample again. As a side benefit, it results in clearer beer than I have gotten when I bottled after two weeks.
 

BearHillEast

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How true is this though? Does an extra set of weeks usually produce a better quality beer, or at least help with sediment deposit?

Thanks!

The longer the beer sits after it has fermented the more sediment drops out and collects. There is a point of diminishing returns with this in that after a certain span of time there's just less there to actually drop out.

The span of time necessary can depend on a number of factors including how much you pitched, what temperature it fermented at (whether it was conducive to the yeast or not), etc.

I think what most homebrewers find is that with their technique they are able to gauge how well a typical beer will ferment out with an average yeast after a few batches. If you have someone making a really effective starter and fermenting in a controlled chamber you're going to have a shorter span of time than someone who doesn't do a starter and makes the yeast work at a temperature it's not comfortable at.

Initially as a homebrewer without doing starters and not having a fermentation chamber I needed 30 days to guarantee that the end product would be of a quality that I didn't feel like it had too much sediment. As time has gone on and I make starters and use a fermentation chamber and can really control the temperature I'm finding better results at an earlier span of time.
 

skraeling

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Hey everyone,

I read a lot of recipe kits declare a fermentation longevity on average of about 2 weeks. But I heard a lot of home brewers like to ferment longer than what is even declared from the recipe, on average a month.

I was just wondering if the extra 2 weeks makes for a better brew, or is this just the ego of the home brewer that we all know and love coming out?

If the recipe is correct, duration wise, why would people let it ferment longer?
If it is better to let ferment longer, why would the recipes disagree? Also, if it is better to let ferment longer at what point would you cease the fermentation process and then start to bottle or leg (type of beer depending)?

Thanks, Brew Force!!!!!
I'm one of those who tends to leave beer in the primary for up to 4 weeks.

It isn't the fermentation that is occurring after two weeks; it's conditioning. I've kegged beer after two weeks that tasted pretty green, but after a couple weeks on the gas, it smooths right out to what I was looking for.

Someone here had suggested leaving the beer in the primary for four weeks as opposed to conditioning in the keg; I tried it and voila! Very nice beer. So it's what I do.

I have a fermenter of Funky Rye that has been there for 23 days sitting and quietly getting better. It's about time to cold-crash it, fine it, and then keg and carbonate it. I might start crashing it tonite, but since I have a partial keg of it on tap, there's no hurry.

That's the beautiful thing about having a pipeline; I've learned patience!
At minium a week. The holiday ale I just did? Took three weeks. It all depends, but ive never had anything actively ferment longer than 4 weeks ever.
 

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