What are the signs of complete fermentation? I understand the only way to tell exactly when it's complete is gravity reading but I'm more interested in signs to know when to even being thinking about checking the gravity. For example, X bubbles every minute, X weeks, krausen has fallen, etc.
Signs of complete fermentation?
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mlyday
Well-Known Member
I usually wait till a week after the bubbles stop to test the gravity. Or just make it easy on yourself and leave it in the primary for 4 week, and your done.
BAOKBrewer
Member
Generally, your fermentation should be complete within 14 days. Usually fermentation is done before then; however, pretty much everybody on this forum will tell you to wait at least 3 weeks before bottling, preferably 4.
If you're really concerned about it (or this is your first batch) you can take a reading whenever you want, as long as you practice good sanitary procedures when taking hydrometer samples. However, if you still have pretty constant bubbling from the airlock, than something is still going on and you might want to wait for it to slow down/stop.
If you're really concerned about it (or this is your first batch) you can take a reading whenever you want, as long as you practice good sanitary procedures when taking hydrometer samples. However, if you still have pretty constant bubbling from the airlock, than something is still going on and you might want to wait for it to slow down/stop.
juslod
Well-Known Member
You still want to measure the gravity after 4 weeks to make sure you didn't have a stalled fermentation. I had a temperature drop in a closet due to the cold weather and my fermentation almost stalled out completely in a Stout, it only dropped from 1.068 to 1.040 in 3 weeks. Moved it to a warmer area and it sprang right up.
mlyday
Well-Known Member
Good Point!
TheBrewinator
Well-Known Member
My general rule of thumb for my brews are pitch and let it sit for 2 weeks. I take a gravity reading at 2 weeks and sample. After that it all depends on the beer but I generally will take a reading again at 3 weeks and then for most beers keg at 4 weeks.
tekknoschtev
Well-Known Member
This is how I go about it. I usually wait the two weeks or so before I take my first reading, and then a few days later take another one. Sometimes though, curiosity sets in and I feel like checking more frequently. This was the main reason I bought a spray bottle and have a starsan solution in it. Makes taking gravity readings a breeze, and I don't have to make up a larger quantity of starsan to sanitize the thief and hydrometer.
GRAVITY READING GRAVITY READING GRAVITY READING!!!!
Unless you take a gravity reading you don't know what's really going on, not by airlock bubbling or by krausen formation. Neither of those signs are effective, they don't tell you exactly where on the fermentation process you are.
The amount of krausen can vary for whatever reason, it can come quick and depart quickly or it can linger long after fermentation is complete, and it all be normal. I've had a krausen stay for 3 weeks EVEN THOUGH MY HYDROMETER READ 1.010 and the beer was done...
And airlocks sometimes bubble or they don't. And airlock is a valve, a vent to release excess co2...NOT a fermentation gauge. It's important to make that distinction, or you'll be panicking everytime a an airlock doesn't bubble, or stops bubbling.
The cat can brush against your fermenter and cause the airlock to stop or start bubbling, changes in temp or atmosphere can cause an airlock to stop bubbling, but that doesn't mean the beer is not fermenting.
Fermentation is not always "dynamic," just because you don't SEE anything happening, doesn't mean that any-thing's wrong,, and also doesn't mean that the yeast are still not working diligently away, doing what they've been doing for over 4,000 years.
That's why you need to take a gravity reading to know how your fermentation is going, NOT go by airlocks, or size of krausen, or a calendar, the horoscope or the phases of the moon (those things in my mind are equally accurate).
The only way to truly know what is going on in your fermenter is with your hydrometer. Like I said here in my blog, which I encourage you to read, Think evaluation before action you sure as HELL wouldn't want a doctor to start cutting on you unless he used the proper diagnostic instuments like x-rays first, right? You wouldn't want him to just take a look in your eyes briefly and say "I'm cutting into your chest first thing in the morning." You would want them to use the right diagnostic tools before the slice and dice, right? You'd cry malpractice, I would hope, if they didn't say they were sending you for an MRI and other things before going in....
Thinking about "doing anything" like repitching, or bottling, or racking, without first taking a hydrometer reading is tantamount to the doctor deciding to cut you open without running any diagnostic tests....Taking one look at you and saying, "Yeah I'm going in." You would really want the doctor to use all means to properly diagnose what's going on?
HickoryMike
Well-Known Member
Even after fermentation is complete, the yeast go back and clean up after themselves. Depending on the style, I would leave it in the primary for 2.5-4 weeks.
clark123456
Member
The 'Think' link seems to be dead. I'm getting a 404 Not Found error message.
Looks like the last forum update may have crashed out the links.
Here https://www.homebrewtalk.com/blogs/revvy/144-think-evaluation-before-action.html
dzlater
Well-Known Member
krausen drops
yeast settles out
beer is clear
but yea it's still best to check with the hydrometer, but you know that
Gunfighter04
Well-Known Member
Not to hijack, but after the fermentation is done, and the yeast and Krausen fall, does the SG continue to drop? Or is it only active fermentation and the addition of alcohol which causes the SG to change?
Once fermentation is over, the SG will not drop any more. At the very tail end, it may drop a little bit but once it's done, it's done. That's why we suggest taking gravity readings three days apart- if it's at 1.012 today, and 1.012 on Friday, that is a sign that it is finished and won't drop any more.
dzlater
Well-Known Member
The gravity does not change after fermentation is complete.
That's why you check the gravity so you know fermentation is complete
The krausen dropping and yeast settling out are just "signs" that it might be done or is close to being done.
That's usually when I'll check to see where it's at, sometimes it needs to drop a few more points sometimes not.
That's why you check the gravity so you know fermentation is complete
The krausen dropping and yeast settling out are just "signs" that it might be done or is close to being done.
That's usually when I'll check to see where it's at, sometimes it needs to drop a few more points sometimes not.
The amount of krausen can vary for whatever reason, it can come quick and depart quickly or it can linger long after fermentation is complete, and it all be normal.
For example, I had a wit beer that I pitched bottle harvested Hoegaarden yeast on Dec. 26th, LAST YEAR that STILL had a 2" krausen on it three weeks later. I took a grav reading and it had reached terminal gravity, 1.010. So the beer was done, but the krausen still lingered. I finally gently swirled the beer to knock it down, and let it settle for another week before I bottled it. I'm not normally a fan of knocking them down, and usually let it do it naturally.
But some yeasts are low flocculating, and may have a difficult time. I figured since mine was bottle harvested, and I had pitched the starter at high krausen, maybe it was "genetically mutated" with the flocculation "gene" off or something. So I gently swirled it and let it fall.
I brewed another batch with another mason jars worth of that yeast several months later and had the same thing happen.
Beligan wits are notoriously long krausening.
So it goes back to the fact that the only reliable guide to how your fermentation is going is.........
For example, I had a wit beer that I pitched bottle harvested Hoegaarden yeast on Dec. 26th, LAST YEAR that STILL had a 2" krausen on it three weeks later. I took a grav reading and it had reached terminal gravity, 1.010. So the beer was done, but the krausen still lingered. I finally gently swirled the beer to knock it down, and let it settle for another week before I bottled it. I'm not normally a fan of knocking them down, and usually let it do it naturally.
But some yeasts are low flocculating, and may have a difficult time. I figured since mine was bottle harvested, and I had pitched the starter at high krausen, maybe it was "genetically mutated" with the flocculation "gene" off or something. So I gently swirled it and let it fall.
I brewed another batch with another mason jars worth of that yeast several months later and had the same thing happen.
Beligan wits are notoriously long krausening.
So it goes back to the fact that the only reliable guide to how your fermentation is going is.........
ongreystreet
Well-Known Member
The SG will change even after fermentation is done!
Saying SG won't change after fermentation is done is true for getting your brew done, but you have to assume since the yeast and other floaters will continue to fall to bottom, and this would lower the gravity of the beer above it. This change probably isn't ever noticeable on your hydrometer, but I am sure somewhere someone is measuring it.
If I am wrong, correct me.
vicratlhead51
Well-Known Member
I'm seeing a lot of ranting about how important gravity readings are. From the way his question was worded I think the OP already knew it was important but he's the same way I am, he'd rather not open his fermentor until he's fairly certain it's done. Less interaction less chance for mess ups with sanitation etc. I think what he's really asking is WHEN he should take samples not IF he should. I like to go 2-3 weeks before opening the lid even if there was only activity for a couple days. In a perfect scenario take one about 2.5 weeks in then another at the end of the week. I'd rather do two readings than half a dozen.
Sorry, but that's a copout, based on fear. (And noone, especially me is "ranting" just stating the facts...There are no other "signs" of fermentation that can be counted on.)
You know, there is so much all over the place telling brewers, what not to do, do you actually think folks would be saying to use your hydrometer so much? Is it a vast conspiracy to ruin millions of new brewer's batches, so that they flee the hobby and give it a bad rap? Every book, every podcast, every posts talks about gravity of beer...how do you think they get them?
The only way to truly know what is going on in your fermenter is with your hydrometer.
WIth proper care and simple sanitization, you run no risk of infecting your beer by taking a simple gravity reading.
Please read this......It's something I think all new brewers really need to read.
I'm going to give you my serious answer to your question, about when you should stop WORRYING about infection. The answer is you should never WORRY about infection, or really anything else about this hobby. Because that is what it is, it is a hobby after all, and a really hard one to screw up.
Now it doesn't mean you ignore proper sanitation practices, and cut corners, or that you don't be careful about things, it is just that you stop thinking of your beer as a weak newborn baby.
It may appear that there's a ton of infection threads, BUT if you actually read the content of the threads, and not just the title, you will realize that there's not a lot of actual infections, just a bunch of scared new brewers who don't realize how ugly fermentation can actually be.
Just like you, I bet, they think that their beer is a lot weaker than it truly is. Just the opposite, it is really really hard to get an infection.
And infections RARELY happen to the new brewers who are so paranoid that they think the mere looking at their fermenters will induce an infection.
Most of the time on here the beer in question is not infected. It's just a nervous new brewer, who THINKS something is wrong when in reality they are just unused to the ugliness that beer making often is.
It creates sort of like the hypochodria that med students often get when they start learning about illness, they start to "feel" it in themselves.
There is a lot of info here on "infections" https://www.homebrewtalk.com/f39/has-anyone-ever-messed-up-batch-96644/
This is one of the best posts on the subject....
If you pitch enough viable, healthy yeast to do their job, it's hard to contaminate your brew to the point it isn't drinkable. Trust me, I've had an infection in my brewery, and I had to work really hard to get it!
BUT A new brewer following sanitary procedures using new equipment is very unlikely to have ruined beer. The worst thing that may happen is your beer will go sour after 4-6 months of room temperature storage. I doubt your beer will last that long.
You'll find that since beer has been made for millenia even before anyone understood germ theory, that even just the basic fact that we have indoor water, clean our living spaces and ourselves regularly and have closed waste systems, and a roof over our heads, that we are lightyears ahead of our ancestor brewers.
And despite the doomsayers who say that ancient beer was consumed young because it would go bad, they forget the fact that most of those beers were usually HOPLESS, and that the biggest reason hops were placed in beers was for it's antisceptic/preservative function.
So even if the beer had to be consumed young, it still must have tasted good enough to those folks most of the time to survive culturally for 4,000 years, and not go the way of pepsi clear or new coke. I'm sure even a few hundred or thousands of years ago, people were discerning enough to know if something tasted good or nasty...
Go take a look at my photo walkthrough of Labatt's first "pioneer" brewery from the 1840's https://www.homebrewtalk.com/f85/labatt-pioneer-brewery-128740/
Wood fermenters, open cooling pans, open doors, cracks in the logs and beams letting air in, and not one bottle of starsan in sight.
The way I figure even just having some soap and water, basic 21st century hygiene, and a basic understanding of germ theory trumps how it was done from Gilgamesh's time through Louis Pasteure's....
In most places we don't have to even worry about boiling our water before drinking it.
Best advice I have for new brewers, If you brew from fear, you won't make great beer!
You might make drinkable beer, or you might make crap...but until your realize that your beer is much hardier than you think it is, you will find that this is much more enjoyable of a hobby.
But infection worry, It is NOT something we have to freak out about, like new brewers do...It's just something to be AWARE of and keep an eye out.
But it's kinda like when you have a brand new car, you park at the far end of the lot away from everyone else, you are paranoid about getting every little scratch on it...Then you are backing out of the garage and take off a mirror, or get a ding on the bumper, then you no-longer stress out about it, because you've popped the cars cherry...If you do pick up a bug, you just treat it and move on.
And the reason I have collected THESE stories is to counter the fear and fear mongering that often happens.
So rather than looking for infections under every bed or in every brew closet, focussing from fear on the negative, I think it's better to look at examples of just how hard it is to screw up our beer, how no matter what we can do to screw up, it still manages to turn out fine.
https://www.homebrewtalk.com/f39/wh...where-your-beer-still-turned-out-great-96780/
And there is a cushion of co2 protecting your beer, so unless you or a bird take a crap in your fermenter, opening it up to take hydrometer readings will not lead you to automatically have infections...
Just relax about infections, and enjoy brewing.
We've said it over and over on here. Krausen's are not a good way to tell. Sometimes they stay when graivty is done. Airlocks are not a good way, they stop and start with impunity, for various and sundry reasons. So all that leaves as a reliable means to know IF fermentation is complete, is a simple 30 second hydrometer reading.
This is what I use, and it works with both buckets and carboys. I replaced the plastic one a year ago with an extra long stainless baster from a kitchen ware store and it is awesome. But the plastic one from any grocery store works fine.
And
Here's what I do....
1) With a spray bottle filled with starsan I spray the lid of my bucket, or the mouth of the carboy, including the bung. Then I spray my turkey baster inside and out with sanitize (or dunking it in a container of sanitizer).
2) Open fermenter.
3) Draw Sample
4) fill sample jar (usualy 2-3 turky baster draws
5)Spray bung or lid with sanitizer again
6) Close lid or bung
6) add hydrometer and take reading
It is less than 30 seconds from the time the lid is removed until it is closed again. More like 15 if you ask me.
Probably less if you have help. And unless a bird flies in your place and lets go with some poop, you should be okay.
And
Here's what I do....
1) With a spray bottle filled with starsan I spray the lid of my bucket, or the mouth of the carboy, including the bung. Then I spray my turkey baster inside and out with sanitize (or dunking it in a container of sanitizer).
2) Open fermenter.
3) Draw Sample
4) fill sample jar (usualy 2-3 turky baster draws
5)Spray bung or lid with sanitizer again
6) Close lid or bung
6) add hydrometer and take reading
It is less than 30 seconds from the time the lid is removed until it is closed again. More like 15 if you ask me.
Probably less if you have help. And unless a bird flies in your place and lets go with some poop, you should be okay.
jwplessner
Well-Known Member
I'll add as a new brewer that checking the gravity regularly is turning out to be a great way to get to understand the beer--the more data, the better. Getting a thief, a spray bottle, and a gallon of reserve sanitizer changed everything. Even without a significant change in gravity I see every time what a day or two can do to a beer, and sometimes it's pretty significant. Then I take notes for use in later batches.
dzlater
Well-Known Member
ok you should take a hydrometer reading after you.....
wait several weeks till you are pretty damn sure it's done
look at the beer and using past experience and observations have a pretty damn good idea that it's done
wait till you feel like bottling or kegging
check it after 2 days and realize it's not done
wait till you run out of beer and decide "hey I need to check on that one in the fermentor"
never take a reading because you don't give a crap what your FG is
or your hydrometer broke and you don't have a spare
your wife/husband is nagging you so decide it might be a good time to go down the basement and "check on that beer"
everyone pretty much agrees you need to take hydrometer readings
to be 100% certain the beer is done fermenting when you do it is really up to you, you won't ruin the beer by doing it too soon or too late, and chances are you won't ruin it by not taking any readings.
wait several weeks till you are pretty damn sure it's done
look at the beer and using past experience and observations have a pretty damn good idea that it's done
wait till you feel like bottling or kegging
check it after 2 days and realize it's not done
wait till you run out of beer and decide "hey I need to check on that one in the fermentor"
never take a reading because you don't give a crap what your FG is
or your hydrometer broke and you don't have a spare
your wife/husband is nagging you so decide it might be a good time to go down the basement and "check on that beer"
everyone pretty much agrees you need to take hydrometer readings
to be 100% certain the beer is done fermenting when you do it is really up to you, you won't ruin the beer by doing it too soon or too late, and chances are you won't ruin it by not taking any readings.
vicratlhead51
Well-Known Member
I'm sorry but I'm not sure where in my post I said not to take readings. I said wait a couple weeks then start reading. Only reason to do so sooner is if you're rushing things which is something I learned not to do from you. I also said in a perfect world you'll only need two readings but we all know its not a perfect world and sometimes there is a need for more. All I was saying is the OP doesn't need to be told he needs to take readings, he knows that. I'm just saying his question is when should he take readings his question states that. I know it varies from batch to batch and after you've done a few you know what to look for but some one new is just looking for some guidelines not a long rant on how important something he already does is.
dzlater
Well-Known Member
Sorry man didn't mean to piss anyone off, I wasn't ranting @ the OP or you. My post certainly wasn't meant to be directed at you.
I was actually agreeing with your post in my sarcastic snarky way.
(usually I just think of those replies and don't actually post them)
Everyone was telling him I wait X# of weeks to check and that wasn't the question.
I thought I gave a simple answer to a simple question when I posted this:
"krausen drops
yeast settles out
beer is clear"
vicratlhead51, I think the op is big enough to "defend" himself if he doesn't like the answers given, but although you seem to be focussed on the fact that we're telling him hydromter hydromter, we're focussed on his phrasing of the REST of his question AND his thread title....
And ALL we're re-iterating is that besides the hydrometer readings there are no OTHER signs that are accurate enough to show complete fermentation. Therefore the hydrometer is the only way.
If the originator of this thread had an issue with our answers I'm sure by now he would have said something, but he hasn't been back. SO methinks he's perfectly satisified with what we've given him. And since then we've been carrying this discussions with other folks- clearing up some of the stuff that popped up since we gave our answers. Including discussions with you....but it seems more like you are interested in picking a fight (like accusing us of ranting.)
You answered your way, we answered our way, and combined the OP probably has enough info to make their decision. So what's your beef? Why all the hate?
And ALL we're re-iterating is that besides the hydrometer readings there are no OTHER signs that are accurate enough to show complete fermentation. Therefore the hydrometer is the only way.
If the originator of this thread had an issue with our answers I'm sure by now he would have said something, but he hasn't been back. SO methinks he's perfectly satisified with what we've given him. And since then we've been carrying this discussions with other folks- clearing up some of the stuff that popped up since we gave our answers. Including discussions with you....but it seems more like you are interested in picking a fight (like accusing us of ranting.)
You answered your way, we answered our way, and combined the OP probably has enough info to make their decision. So what's your beef? Why all the hate?
Correct.
vicratlhead51
Well-Known Member
There's no hate, actually my second post I think I hit the quote button when I meant to hit the reply. The only hate I have is that I can't convey emotions or in this case lack thereof. My second post was only defending my first one, not anyone else's. All I was basically saying was that I thought the focus of many of the replies to this thread was on the wrong part of the original question then added my opinion, that's it. No hate, no fight, IRL I'm just a jolly ol' fatman, I don't think I can get the right inflections out in writing, just not good at it I guess.
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