Fermenter seal and fermentation/cold crashing

[Jason D Cook]

Hi all -

I'm currently conditioning my second-ever beer. My process has improved considerably since my first attempt.

I use a fermenter that I got locally here in the Philippines (wide mouth, blue opaque polycarbonate like Northern Brewers' BMB). The gasket is wanting, however, and I'm not too sure about the grommet for the airlock. I'm taking steps to rectify both trouble spots but I'm wondering:

Beyond allowing O2 in and possibly skunking beer, does a tighter/looser seal on a fermenter affect fermentation or cold crashing?

I seem to have a lot of gunk in suspension with this second beer (Dead Ringer from NB) and although I cold crashed from 60-degrees to 40, nothing ever got sucked back out of my 3-piece airlock (indicating a possible leaky lid gasket).

So does a tight fermenter increase fermentation and the effects of cold crashing?

 

[Vale71]

Hi all -

So does a tight fermenter increase fermentation and the effects of cold crashing?

No, why would it? A tight seal is not going to make your beer colder or the yeast work harder, it will however prevent (to some extent) the ingress of O2.

 

[mongoose33]

No, it's the temperatures that matter.

You're spot on to be concerned about O2--though unless you have a closed system to return CO2 to the fermenter as it cools and the headspace contracts, you're going to draw air in anyway.

As you crash a 5-gallon batch from, say, mid-60s to mid-30s, your headspace is probably going to contract as much as a quart of volume. That creates a partial vacuum, and it is filled by air going in through the airlock.

There are ways to deal with this--among them is to capture the CO2 produced during fermentation then feed that back during the crash.

Not sure this is even an option given your location, but you could make something like it; I have. https://www.brewhardware.com/product_p/ccguardianv2.htm I've used plastic bags (such as bread bags) to capture CO2 toward the end of fermentation, then it feeds it back during crash.



You can also make up something like this: https://www.norcalbrewingsolutions.com/store/CO2-Carbon-Dioxide-Harvester-Kit.html It's a little pricey, but if you're handy, you can make up something like this; I have.

 

[Vale71]

While there is some merit to preventing O2 ingress when reducing temperature one should be aware that given time there will always be some O2 ingress in a non-pressurized vessel. Only a vessel with positive pressure such as a keg or unitank gives you a 100% guarantee of no O2 ingress.
Diffusion: you can't fight it, you can't live without it (literally, your cells would asphyxiate quickly...)

 

[mongoose33]

The name of the game is to reduce O2 exposure post-fermentation as much as possible. While perfection may be unobtainable, you can do pretty well if you work at it over time.

And, @Jason D Cook , you're working on that. IMO, one of the best ways new brewers can approach all this is to use a process of continuous quality improvement. That is, every time you brew, try to do something better. Sounds like you already have that mindset ("My process has improved considerably since my first attempt").

There are many places you can do that. Ones that most brewers would probably tell you were important for them are fermentation temp control (sounds like you're already there), mash temp control (if you're doing all-grain), and controlling oxygen ingress post-fermentation (which you're aware of).

So, congrats on the second beer and keep at it. Every time, do something better.

 

[Jason D Cook]

There are ways to deal with this--among them is to capture the CO2 produced during fermentation then feed that back during the crash.

Thanks, man. That was really helpful. I have a friend here who owns a party store so I'm going to look for a "Happy Beer Day" balloon and try that when I next crash.


I'm gonna seal up everything the best I can, though, and try to figure out why I have so much stuff in suspension.

 

[Jason D Cook]

The name of the game is to reduce O2 exposure post-fermentation as much as possible. While perfection may be unobtainable, you can do pretty well if you work at it over time.

And, @Jason D Cook , you're working on that. IMO, one of the best ways new brewers can approach all this is to use a process of continuous quality improvement. That is, every time you brew, try to do something better. Sounds like you already have that mindset ("My process has improved considerably since my first attempt").

There are many places you can do that. Ones that most brewers would probably tell you were important for them are fermentation temp control (sounds like you're already there), mash temp control (if you're doing all-grain), and controlling oxygen ingress post-fermentation (which you're aware of).

So, congrats on the second beer and keep at it. Every time, do something better.

Man, that was really nice and an ego boost, too. Thank you.

I'm trying not to hit a wall and give up with this hobby. My first brew was a screaming comedy of errors on bottling day. My second, so much smoother.

I mean, I know the O2 question is important but less so when you guzzle your results as I do.

I should maybe be looking at conditions before the fermenter since I have so much trub and crap in suspension.

Thanks, @mongoose33. Thanks, everyone. This forum is quite a blessing.

 

[mongoose33]

During active fermentation, your wort/beer looks like a maelstrom of crap you'd never want to drink. I think it's fascinating to watch it roiling around. The beer...it's alive!

Once fermentation is complete--the krausen has fallen, and you can see the top surface of the beer--your beer should be clearing. If there's stuff floating in the beer and it's not falling out, that's probably a process issue.

Here's a pic of one of my fermenting beers before I got my ferm chambers; looks pretty unappealing, doesn't it? Turned out great.



For a lot of brewers, some of the fun is figuring this all out. How to gin up some equipment to accomplish some aspect of brewing they want done. You are already doing that and it's only your second brew.

One thing a lot of brewers use is something called "Whirlfloc." It's carrageenan or some sort of seaweed/algae extract, and it's added with 15 minutes to go in the boil. This helps precipitate stuff out of the wort resulting in a clearer beer. I use it.

 

[Jason D Cook]

During active fermentation, your wort/beer looks like a maelstrom of crap you'd never want to drink. I think it's fascinating to watch it roiling around. The beer...it's alive!

Once fermentation is complete--the krausen has fallen, and you can see the top surface of the beer--your beer should be clearing. If there's stuff floating in the beer and it's not falling out, that's probably a process issue.

Here's a pic of one of my fermenting beers before I got my ferm chambers; looks pretty unappealing, doesn't it? Turned out great.

View attachment 596738

For a lot of brewers, some of the fun is figuring this all out. How to gin up some equipment to accomplish some aspect of brewing they want done. You are already doing that and it's only your second brew.

One thing a lot of brewers use is something called "Whirlfloc." It's carrageenan or some sort of seaweed/algae extract, and it's added with 15 minutes to go in the boil. This helps precipitate stuff out of the wort resulting in a clearer beer. I use it.

Thanks, man. Yeah, I read so much stuff before I started but no one mentioned the churning fermenter bit. It really freaked me out!

This is what I had with the NB Dead Ringer kit after straining by hand in my 5-gallon fermenter.

Maybe at this point, I've gone beyond the scope of this subject line.

 

[Jason D Cook]

Oh, and I threw a Whirlfoc tablet in at 15-minutes left in the boil but... It didn't seem to do much.

 

[balrog]

Patience, grasshopper. Patience.
Generally speaking, your yeast will clear to let you know the beer is ready; notable wheat/Kolsch styles being the exception. Patience.