can you lose batch volume when using blowoff

olotti · Sep 10, 2014

I have a huge RIS in the midst of primary fermentation prob 12 hrs into it. There is almost a steady stream of foam coming through the blowoff tube. I racked 5.5 gal into a 6.5 gal carboy before I pitched the starter so I know the volume was correct. Now the batch volume is at the 5.25 gal mark. Is it poss or how am I losing volume?? Is that what's heading out the end of the blowoff tube.

Derrminator · Sep 10, 2014

Yep, you can lose some volume out of the blowoff tube but I wouldn't worry too much. After all its doing its job and you'll still have plenty of good beer left.

Spartan1979 · Sep 10, 2014

Yes, the foam contains (is) beer. Has the volume of the container that you're blowing off into increased?

olotti · Sep 10, 2014

Spartan1979 said:
Yes, the foam contains (is) beer. Has the volume of the container that you're blowing off into increased?

Not really I just have to go downstairs and scoop foam off of it like every hour, its as dark as the reg beer but no increase in volume of blowoff vessel, the blowoff vessel literally has a krausen of it's own. As far as final volume well at 10.8% even 4.75-5 gal will b plenty to bottle.

Spartan1979 · Sep 10, 2014

olotti said:
Not really I just have to go downstairs and scoop foam off of it like every hour, its as dark as the reg beer but no increase in volume of blowoff vessel, the blowoff vessel literally has a krausen of it's own. As far as final volume well at 10.8% even 4.75-5 gal will b plenty to bottle.

If you had a larger container for your blowoff, you'd see that it would have risen by the same amount the primary went down.

When I was fermenting in a 6 gallon Better Bottle, I'd often lose 1/2 gallon on an active fermentation.

olotti · Sep 10, 2014

Spartan1979 said:
If you had a larger container for your blowoff, you'd see that it would have risen by the same amount the primary went down.

When I was fermenting in a 6 gallon Better Bottle, I'd often lose 1/2 gallon on an active fermentation.

Thanks for the replies. This was a side effect I just never really considered. I did see in a thread where one guy with a beer this big split the batch into two carboys so as not to lose all this to blowoff. Def think that's what I'm going to do next time.