Fermentation Blow off Conditions

Hi guys....had a interesting thing happen during the fermentation of this AG batch I'm doing.

I've read about guys having fermentation's that need a blow off tube. After about 15 or 20 batches, I don't think I've ever been in that situation before. I'm not sure if it is because of the extra head space I normally have in my brews or what, but i've never been in a position to really need one. Normally I have 5 gallons in a 6 gallon carboy.

With that said....I did a batch this weekend where I missed my SG (for silly reason) to go into the fermenter and didn't add the top off water that I would normally done to get to 5 Gallons. It ended up at 4.75 gallons.

This is a very simple American ale with 1056 yeast and 6lb 2-row, 1.75lb flaked corn, 1/2lb flaked rice, and .5lb carapils. Very basic lawnmower beer.

I had .75 lb of carapils left over from previous batch and put that in instead of just .5lb. Also during the boil, I missed putting the whirliflock in at 5 to 10min from end.

This time during the ferment if I didn't have that extra head space I would have needed to put a blowoff tube in.

I'm wondering if the additional proteins from the extra Carapils and missing the whirliflock that the additional proteins caused this huge krausen on the top? It is a fairly good ferment but not overly vigorous but still has a huge head on it.

Anyone else see something similar or have any ideas?

Do you have a ferm chamber, or do you ferment in your closet?

If you don't like washing your ceiling.... Start EVERY fermentation with a blow off tube set up. I control my temperatures well, use 6 gallon Better Bottles for 5.25 gallons in most cases. I have done all kinds of beers with many different yeasts. I have not seen that there is any real way to determine which ones will produce a lot of krausen.

I have even done what would seem to be simple beers using the same yeast and one will blow off and the next will not.

I think that temperature has a lot to do with it. If I ferment at 62 degrees I don't seem to need a blow off. I'm doing a Bell's Two Hearted clone right now at 65 degrees and it's just foaming up enough to need one.

Ive had 5 gallon batches in a 7 gallon carboy that needed a blowoff tube. Most batches are fine, but Id rather my closet only have beer in carboys and bottles, not anywhere else


Sent from my iPhone using Home Brew