Why check for complete fermentation?

[YeastFeast]

I've read over and over on the forum to leave your beer (ale's specifically) in your primary for 3-4 weeks and then bottle. So what's the point of checking the gravity, and then again in 3 days, to find out if your fermentation is complete? Certainly the fermentation process would be long done for an ale in 3-4 weeks?

There must be other reasons I don't know about?

Thanks for your feedback!

 

[kellynm]

To calculate your ABV maybe?

 

[n240sxguy]

It's just for safety's sake if you are bottling. I've only had one beer that wasn't done in two weeks. It was my pumpkin. It took several days to take off really good. I just check it before I keg to see if it is close to where I think it should be. If you bottle it, and it isn't done, they go boom!

 

[YeastFeast]

To calculate your ABV maybe?

That certainly makes sense.

 

[YeastFeast]

It's just for safety's sake if you are bottling. I've only had one beer that wasn't done in two weeks. It was my pumpkin. It took several days to take off really good. I just check it before I keg to see if it is close to where I think it should be. If you bottle it, and it isn't done, they go boom!

OK. Guess I just thought there was no way fermentation would still be going on after 10-14 days or so, never mind 21-28 days. Guess all beers/yeasts are different though?

 

[Bobby_M]

Frankly, I've never suggested checking gravity three days in a row. This advice is typical for newer brewers though because they are in such a rush to finish the beer that they will, and often do, bottle 4-5 days after pitching yeast.

 

[n240sxguy]

OK. Guess I just thought there was no way fermentation would still be going on after 10-14 days or so, never mind 21-28 days. Guess all beers/yeasts are different though?

The FG on my pumpkin ale kept dropping for nearly 5 weeks. Went to like 1.006. I had to back sweeten it with lactose to have any body at all. It is basically an imperial pumpkin at 7.9%.

 

[Desvio]

I give them a minimum of three weeks no matter what, and since I travel with work a lot this is never a problem.

There is never any problems with giving them a little extra time, but there are all kinds of problems with doing it early, bottle bombs can be scary when they go off.

 

[nukebrewer]

Also, if fermentation gets stuck for whatever reason, you kinda want to know about it. If it sticks way above your expected FG and you bottle you'll end up with anywhere from a slightly too sweet to very cloyingly sweet beer along with potential bottle bombs if the priming sugar restarts the fermentation process. Better to fix an issue like this before bottling than having to dump a batch just because you were too lazy/didn't want to sacrifice the few ounces of beer for a gravity sample.

 

[fartinmartin]

You need to know that it's done and not just having a break
You need to know for the abv
You need to know for your record keeping
Don't gamble with bottle bombs
So when you are pretty sure that it's finished on instinct, be totally sure by taking the SG.

 

[C-Rider]

Never had a stuck fermentation.
Never check FG until bottling day
Always ferment for at least 3 weeks, more often 4 weeks.
My imperial stout sat for 7 weeks.

 

[Qhrumphf]

Frankly, I've never suggested checking gravity three days in a row. This advice is typical for newer brewers though because they are in such a rush to finish the beer that they will, and often do, bottle 4-5 days after pitching yeast.

Also, if fermentation gets stuck for whatever reason, you kinda want to know about it. If it sticks way above your expected FG and you bottle you'll end up with anywhere from a slightly too sweet to very cloyingly sweet beer along with potential bottle bombs if the priming sugar restarts the fermentation process. Better to fix an issue like this before bottling than having to dump a batch just because you were too lazy/didn't want to sacrifice the few ounces of beer for a gravity sample.

I advocate checking over 3 days to new brewers, but I'm confident enough with my brews and my process to know what to expect and am rarely ever surprised. Normally I'll check FG at about 2 weeks, and then usually give it another 1-3 weeks more depending on the beer. If something is off, I'll check it again later.

But, it's a matter of safety to make sure fermentation is done. And I do make sure I double check to make sure it's done when I'm using a finicky strain (say, the Dupont strain), or when I'm using a strain I've never used before and I'm not sure what to expect.

 

[BetterSense]

If I take a gravity reading after pitching, it's just so I have a final gravity to write in my journal. I let my beers settle for at least a week or two after signs of fermentation are over. What's the rush? If you are in a hurry, you need a deeper pipeline.

 

[Potamus]

I usually leave my beers in the primary for three to four weeks. I take a single final gravity reading to calculate ABV, and if it's in the range I expected, I bottle. Never had a problem yet.

 

[fuelish]

What's the rush? If you are in a hurry, you need a deeper pipeline.

Indeed....if you're in that big of a rush, just go out and buy some good beer, relax and enjoy, and have you'll a few more empty bottles on hand.... I like having some swing-top bottles on hand, as the rubber grommets can also double as incredibly effective low-budget "strap-locks" for guitars
Yup....guitars, homebrew, mountainbike, guns...life is pretty good...

 

[green_bierz]

reasons i check gravity even though i no longer bottle my beers.
simply because im anal about it and we are brewers, so thats what we do lol.

second reason you check gravity and for complete fermentation. when you bottle you dont want to make a new thread with the title of "BOOM" lol

 

[RM-MN]

I usually leave my beers in the primary for three to four weeks. I take a single final gravity reading to calculate ABV, and if it's in the range I expected, I bottle. Never had a problem yet.

Just wait, you'll get a surprise someday just like I did. Beer in the fermenter for 3 weeks, took the hydrometer reading and it was right on the expected FG. Weighed out my priming sugar, a little lower than called for since I wanted a lower amount of carbonation and bottled. A month later when I opened a bottle it was overcarbonated, badly overcarbonated. A couple months later I discovered that 2 bottles had blown the bottom out.

Last month I had a pale ale that at 2 weeks was at 1.016, the expected FG so I dry hopped it. 3 days later the airlock was bubbling again but I thought it was probably just CO2 coming out of suspension. A week after dry hopping I checked the gravity again and it was at 1.006 and the airlock was still bubbling. It finally quit when the gravity got down to 1.002 and stayed steady for a week. Had I bottled this at 3 weeks I would have had bottle bombs by week 4.