Fermentation and time

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Griff097

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Reading some posts got me thinking, rare I know, but on occasion I do it.

I am developing some habits, some bad possibly of making assumptions, like not checking gravity until 10 days ish and then doing a comparison a day or so later and cold crashing.

I have read that extra time beyond the few days it takes to complete fermentation of my beer allows for the yeast to "clean up" and hence get clearer beer.

Is this true?

What do you do?
 
The extra time you are referring to is important so that the yeast has enough time to clean up unwanted compounds (such as alpha-acetolactate which will later be converted into diacetyl) that are created during the fermentation process

However, 10 days is probably sufficient for that to happen anyway. A typical fermentation for me is complete (i.e. final gravity is reached) after about 4 days. I then raise the temperature a couple of degrees and wait 3 more days for the yeast to clean up.

I then do a forced diacetyl test to make sure everything is ok before cold crashing/dry hopping. If needed I wait another 24 hours and test again and so on.
 
Cripes. I just taste it.

Unfortunately you can't taste alpha-acetolactate so you won't know it is there until later when it has been turned into diacetyl, at which point it's too late as yeast may not be able to consume it.

It is only really a problem if you are trying to get things done quickly. If you leave your beer alone for 10-14 days at fermentation temperature then it should all be cleared up.

I just like to be on the safe side as I've been caught out in the past and a butterscotch beer isn't usually what I'm after! 🙈
 
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Reading some posts got me thinking, rare I know, but on occasion I do it.

I am developing some habits, some bad possibly of making assumptions, like not checking gravity until 10 days ish and then doing a comparison a day or so later and cold crashing.

I have read that extra time beyond the few days it takes to complete fermentation of my beer allows for the yeast to "clean up" and hence get clearer beer.

Is this true?

What do you do?
Depends what you mean by bad habits.

If you are not checking gravity until 10 days then there is probably no point taking another reading as (as mentioned above) final gravity (or very close to it) will be reached sometime in the first few days for most beers. However, I wouldn't call leaving it alone for 10 days as a bad habit.

Again, as above, the end of primary fermentation overlaps with the yeast 'cleaning up' which you can accelerate by bumping the temperature up before primary has completed. If you wanted your beer fast you could do this.

Last question is the difficult one. Sometimes I control and monitor the brew, look at the graphs my control system produces and make decisions on when to move to the next stage (or programme it to do it for me). Sometimes I put them in a temperature controlled chamber but just leave it. With others I put the FV in a spare room and have a look every few days.

Thinking about it, a bad habit would be one that results in bad beer. Not the case with your beer though is it ?
 
Thinking about it, a bad habit would be one that results in bad beer. Not the case with your beer though is it ?

I'd probably think of this in a slightly different, albeit very similar way: A bad habit is one that could result in bad beer.

It's possible (definitely not saying it is the case here) the OP has never had a bad beer through blind luck and may change something in their process in the future that exposes them to the risk posed by their bad habit.

Cleaning and sanitising are a good example. I'm sure we all get a little lazy with that at some point and for the most part it isn't an issue. But there is still a risk that it could cause big problems if something goes wrong.

In this particular case, I don't believe the 'bad habit' of not testing the gravity until after 10 days really carries much risk. As long as the OP doesn't start shortening the time beer is left in the fermenter before cold crashing, then it shouldn't make any difference to the final beer when the gravity is first tested.
 
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Thinking about it, a bad habit would be one that results in bad beer. Not the case with your beer though is it ?
Probably a poor choice of words, lazy habit maybe, when fitting in around a busy workload?

It goes back to the old 2 2 2 for timing I guess, so when I started I would be checking every day, then after a while realized your throwing 50cc of beer away every time so looked at the average times and tend to leave it 10 days ish to check and then recheck.

Bad beer, not really, sometimes not what I was expecting but virtually every brew is different so to be expected I guess.

Yeast quality has got to play a part as well, the liquid wlp04 I used in an Irish Red is done and the dry yeast from another batch is still slowly dropping on day 9.
 
I do similar to what you do, perhaps longer than 10 days, I also rarely bother with gravity readings as I've confidence in the yeast I use and my process.

This podcast covers this topic. Basically, fermentation is two stage, reaching attenuation, then maturation. At 10 days, you probably aren't doing the thing they say to avoid, which is reaching attenuation then cold crashing, missing out maturation.

https://podcasts.google.com/feed/aH...TQtMGQ3MC00MmI4LTg0ODQtYzJiZWM5ZDAzNTYw?ep=14
 
Reading some posts got me thinking, rare I know, but on occasion I do it.

I am developing some habits, some bad possibly of making assumptions, like not checking gravity until 10 days ish and then doing a comparison a day or so later and cold crashing.

I have read that extra time beyond the few days it takes to complete fermentation of my beer allows for the yeast to "clean up" and hence get clearer beer.

Is this true?

What do you do?
What I do is keep the temperature within limits, take gravity readings, and as it is in an open fermenter look at the surface of the stuff to see what's going on. That's where the experience comes in.
 
I'd probably think of this in a slightly different, albeit very similar way: A bad habit is one that could result in bad beer.

It's possible (definitely not saying it is the case here) the OP has never had a bad beer through blind luck and may change something in their process in the future that exposes them to the risk posed by their bad habit.

Cleaning and sanitising are a good example. I'm sure we all get a little lazy with that at some point and for the most part it isn't an issue. But there is still a risk that it could cause big problems if something goes wrong.

In this particular case, I don't believe the 'bad habit' of not testing the gravity until after 10 days really carries much risk. As long as the OP doesn't start shortening the time beer is left in the fermenter before cold crashing, then it shouldn't make any difference to the final beer when the gravity is first tested.
Yes, I'd had similar thoughts after I posted, doing something that has the potential to cause ill effects.
 
I am developing some habits, some bad possibly of making assumptions, like not checking gravity until 10 days ish and then doing a comparison a day or so later and cold crashing.
So let's turn this around and ask what you would have done differently and how (if at all?) your different decisions would affect your beer if you had measured earlier.

So let's say you would have measured the gravity earlier. If it hadn't finished fermenting, your behaviour wouldn't have changed, so the beer would be unaffected.

If it had finished fermenting, you would have left it the appropriate time for a diacetyl rest, yeast cleanup etc, then cold crashed and packaged. But we've seen time and time again there are no difference in letting the beer sit on the yeast an extra week or three. So whilst your behaviour would have changed, the finished beer wouldn't have. The only difference would be that the beer would be packaged earlier (so you can get another brew on, or tidy stuff away earlier) or that the beer is ready to be drunk earlier. If those aren't important to you, then there is no benefit in measuring the gravity earlier.

It's what I like to call the difference between "useful" and "interesting" information. One is used to positively change an outcome, the other isn't. I don't think measuring the gravity for the first time on day 10 is a bad habit
 
So let's say you would have measured the gravity earlier. If it hadn't finished fermenting, your behaviour wouldn't have changed, so the beer would be unaffected.
Interesting you mention that, the one time due to pressure of work etc that I left a beer in the FV for 6 weeks, it developed a moldy skum on the top and I chucked it out.
 

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