Excessive Fermentation

[Hank Plantagenet]

So, I double-pitched my Imperial Stout on Saturday night in my standard plastic bucket. When I woke Sunday morning, the airlock was bubbling happily. Took the kids to the park, and upon my return I found that the froth (krausen?) had filled the airlock. I put a clean airlock on it and started some yardwork. When I came back inside, the bucket was actually BULGING (top AND sides), and I was getting bubbling all along the gasket as well as the airlock. There was a big pile of huge frothy goo all on top of the fermenter around the airlock.

To prevent an explosion, I just pulled the airlock out of the bung and let it ferment away. (I also put the fermenter inside my big kettle to catch any overflow before it hit the floor.). By this morning, ithe fermentation had settled down, and I put the airlock back on and cleaned the top of the lid. The batch is now bubbling away at a rate of about 40 normal bubbles per minute or a bit more.

Was there a better solution than just pulling the airlock?

I am considering drilling holes for two more airlocks in one of my lids, for use on really big beers. Would three airlocks do the job for a high gravity beer?

 

[Mark D Pirate]

Larger diameter blow off tube or plenty of head space should prevent blow outs like that , I have seen friends add extra fermentables at 48-72 hours with huge gravity beers to help alleviate this

 

[ACBEV]

Would'nt worry about not having an air lock, put it back when it settles down. Many brew without.

 

[sn00ky]

+1 on blowoff tube - I just used one for a high gravity ale and quite thankful for taking others' advice.

 

[jeffpn]

Head space is what you need. You have to take into account how thick the krausen will get. It has to be somewhere. Or take the bobble out of your airlock, and slip a hose over the part where the bobble sits. Run the hose into a bucket of water. I don't think multiple airlocks is your solution.

 

[J A]

We're gonna need a bigger bucket.

Another vote for blowoff tube, too. Always assume a double pitch, big starter or pitching on a cake will go a little nuts. I've had it happen pretty routinely even with .060 IPA's and even smaller gravity beers.

 

[Head First]

I'm on brew #143. I learned that a blow off tube was needed on my #1 brew. I do have modified bubblers that the little lid has bigger holes so it won't plug as easily. Head space in fermenter is a must with bigger beers also. More holes won't keep the krausen from overflowing the bucket and plugging the vents. I even read at one time that it was good to lose some of the krausen for better beer. Don't remember where that was though.

 

[Ozarks Mountain Brewery]

Ive also lost too much and had poor attenuation so its better when faced with a bomb to just take off the lid if using buckets to keep it from shooting out like a restricted water hose

 

[GFHomebrew]

How's she going now Hank things calming down in your brew house?

 

[J A]

Ive also lost too much and had poor attenuation

Just had that happen with my Black IPA...pitched on a 3rd gen cake because I really just had to get it going. It got going alright.
Within 3 hours of pitching, it was full krausen, even with the temp held in the low 60's. I put a big blow off on it before leaving it for the night and by morning it was puking out foam. By the time it calmed down enough to put the lock back on it, there was enough yeast in the bottom of the blow-off bucket to easily start another 5 gallon batch.
It's supposed to go down to .012 but it's hanging hard near .015. I don't doubt that losing yeast and blasting through fermentation has had an effect on the FG. Not too worried about this one, though...it's already a 7.25 ABV beer with huge hops. I'm not going to mind a little extra residual if it stays.

 

[Mark D Pirate]

Unless you're still using bottles like I am ....bottle bombs are a nightmare !

 

[ACBEV]

I like to brew big beers from time to time...

My rule of thumb...

Big bucket. at least 1/3rd head space.
Bucket placed on a large catch tray (large plant pot type will do)
I take the lid off bucket when it gets going. As long as the air is still and its not disturbed, having the lid off should be fine.
Put the lid on when it settles.

 

[Hank Plantagenet]

How's she going now Hank things calming down in your brew house?

Settled down nicely. I will be checking the gravity later today.

On big beers in the future, I am thinking that I will split the batch into two fermenters after the boil, so that I will have plenty (maybe even "excess") head space for krazy kräusen. I can then re-combine the two sub-batches in secondary.


ETA: This thing is already down to 1.031 in approximately 80 hours. That is almost 10% alcohol in barely three days. Wow. Tastes pretty good, too, though it will clearly need some aging.

 

[Ozarks Mountain Brewery]

good idea. right now I have a gallon head space and thats still not enough in my 12 gallon batches