Thinking I May Have Lost One

[dan_s]

Hello Everyone,

I have a Kolsh that has been fermenting happily at 60* for the past 2 weeks in my refrigerator downstairs. Yesterday I lowered the Johnson control unit to 35*. This morning when I went to remove the blow off tube from the carboy to replace it with an airlock, I saw that the 6 gallon carboy was filled completely to the top, which was not the case 2 weeks ago when I poured ~5.5 gallons of chilled wort into it. My guess is that as the temperature dropped last night, water from the blow off bucket was sucked back into the carboy until it filled to capacity. I can’t think of any other explanation.

At this point I am guessing that the batch is probably lost and would at best be greatly diluted or at worst, infected (the blow off water that was sucked back into the carboy was pretty nasty looking). Would anyone have any thoughts on where to go from here?

[stompwampa]

Was your blowoff water a proper mix of StarSan?

How does it smell? Did you taste a sample?

It won’t hurt anything to bottle or keg it and let the beer finish out.

You can always dump it later if it’s bad. If smell and taste at this point seem okay, then give it a chance. Better to give it a chance now as opposed to dumping would could still be a fine batch of beer.

[dan_s]

Thanks, stompwampa.

The blow off liquid was straight up tap water and was drawn back into the beer after fermentation was complete.

Would anyone have a link to a calculator that would tell me what the new ABV of the beer would be if I had ~5.5 gallons of 5.25% beer that was diluted with ~1 gallon of water after fermentation (I’m guessing that a standard calculator using OG/FG would not work due to the change in volume)? For that matter, does anyone know the actual capacity of a 6 gallon carboy, including headspace?

I was thinking that if the beer was not overly-weak, adding gelatin, racking and then lagering the beer for a month or so might help to drop out and offset any undesirables that would have been sucked back in with the blow off water.

[old_dawg]

I’m not an artihmetologist, but my arithmetic says you diluted the alcohol to 92% of the original, which is about 4.8%. (The ratio of the old volume to the new volume is 0.92, so the alcohol would have been diluted to 92% of the original.)

You may also have begun an experiment with soured beer, which a lot of people think is a good thing.

You’ve invested time and materials in it, try lagering it for a while.