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Subject: How do I know when fermentation is done?
Author: Newbrew2010
Feb 3rd, 2010
12:01 am
Is there an easy way to tell when a brew is done fermenting. My last home brew i made was a pale ale, I let it ferment for 7 days and then bottled it and it turned out great. Is 7 days the usual time to let a beer ferment or does it depend on the style of beer you are making. I have a Hefeweizen in my carboy fermenting right now, and just wanted to know how to tell when fermenting is done. thanx
Subject: Re: How do I know when fermentation is done?
Author: brewkid
Feb 3rd, 2010
12:06 am
mine are usually finished in around 7 or 8, but ive had them finish in 3 days and some in 10 days. it depends on all sorts of stuff, the yeast, the gravity of the beer. I shine a cellphone through my batches to see if i can see the light from the other side, and then take a gravity reading, but since is a hefeweizen you should take a gravity reading. if you have doubts just wait.
Subject: Re: How do I know when fermentation is done?
Author: djeffbee
Feb 3rd, 2010
12:06 am
Most likely it is done, but the only way to be sure is to take a gravity reading... What was the OG?


Edit - Aidan beat me to it
Subject: Re: How do I know when fermentation is done?
Author: mpbrewer
Feb 3rd, 2010
12:07 am
Hey newbrew2010. the sure fire way is to take another gravity reading. the recipe you followed should have had an O.G. (original gravity) and an F.G. (final gravity) listed. they may have been termed anticipated OG/FG. so take a reading and compare to the recipe.
Subject: Re: How do I know when fermentation is done?
Author: jjbrewhead
Feb 3rd, 2010
12:13 am
Excellent muddypuddle, the sure way is taking a gravity reading, I give mine (depending on the brew)
at least 10days then check with the hydrometer. I always log every brew. O.G./F.G. Safe/then Sorry.
Subject: Re: How do I know when fermentation is done?
Author: OneHoppyGuy
Feb 3rd, 2010
12:18 am
7 days is VERY short. To know if primary fermentation is done is to measure the specific gravity. If the gravity is within the expected range, then it is done with it's primary fermenting. However, the time to reach the expected gravity is based on many factors: type of beer, original gravity, type of yeast, fermenting temperature, health of yeast at pitching, amount of oxygen yeast received at pitching, the shoes you were wearing and the moon's phase.
But wait! There's more!!! Just because the desired gravity has been reached, the beer still needs time. This is where you will get 1,483 opinions from each person on the website. I age mine in the primary for two or until it hits the gravity I am looking for whichever is longer. Then I transfer to a secondary and let it sit for 2 to 3 weeks. I keg, so from there the beer is 'crashed' dropped to about 38 degrees for a few days (sorta like a bright tank) and then I filter. Even I don't have this written in stone, if it's a really big beer I let it sit for a couple of months. If it's a session beer (-1.035 - 4% ABV) it's two and a half to three weeks from brew to drink.
Whew!
I hope that helps
Subject: Re: How do I know when fermentation is done?
Author: henrythe9th
Feb 3rd, 2010
12:55 am
usually go around 30 days in primary, (no sec,) but depends on the beer, I'm bottling a English brown tonight that was brewed on jan 10th..
but the black IPA (brewed the same day jan 10,) will be dry hopping for atleast 2 more weeks..
again FG is what matters most, but longer means clearer beer I don't even check gravity for at least 3 weeks after brewing.
time is of a essence more = better beer
Subject: Re: How do I know when fermentation is done?
Author: jtrainer
Feb 3rd, 2010
3:01 am
The only true way to tell if your done is multiple gravity readings over a few days. If no change is measured for a few days your done (or should be). There are a number of reasons you may not be at the expected FG especially if done as an extract.

I typically primary for 2 weeks minimum before I think about racking to keg.I've had beers in the keg and serving on day 11.... That was a major rush job and I think it showed.

Subject: Re: How do I know when fermentation is done?
Author: Angler
Feb 3rd, 2010
10:44 am
When I first started brewing I was impatient, despite being an accomplished dry fly fisher. Over time I acquired even more patience, and now when I brew after I see the airlock start bubbling I usually don't even look at that fermenter for two weeks**.

You never know just how your yeast is going to act. Just when you think you've got it figured out it pulls a fast one on you. I recently had a 10% abv beer finish it's primary fermentation in about six days with a one gallon starter, 60 degree ferm temp, and minimal aeration**. And it's a really good brew**. Normally I don't even check gravity until about two weeks, but since I used small incremental infusions of refined sugar which I haven't done a lot of in the past, I did more checks than normal and was stupefied when I saw the readings. At three weeks I'm hesitant to keg/bottle because know that a the brew will benefit from some aging.

All that said, seven days is a short time to get to bottling/kegging**. I'd dump a hefe into bottles/kegs in two weeks, but prolly not before then and if I did do it at two weeks I'd have a dryer lint filter over the racking tube to keep the "chunks" out**.

I haven't done a freakin' secondary since my 3rd or 4th brew and I'm all the happier for it**. Let it sit on the cake until it's time to bottle/keg IMHO. The only thing a secondary is good for is creating another opportunity for infection**.

** I brew shitty beer don't listen to a word that I say.
Subject: Re: How do I know when fermentation is done?
Author: DavidS
Feb 3rd, 2010
11:35 am
Time, time, time is on my side, yes it is
Subject: Re: How do I know when fermentation is done?
Author: OneHoppyGuy
Feb 3rd, 2010
2:54 pm
BB has all the time in the world

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