Hi all. I’m hoping someone can explain what I am seeing. I brewed a Belgian Trippel a couple of months ago. It was in a secondary fermenter and was clearing up nicely. The temperature went up to about 72 from 68 or so in my basement. It started clouding up and is now bubbling again. I am a greenhorn with this being only my 4th batch. What’s going on?
You may be seeing dissolved CO2 coming out of solution due to the temperature increase. The cloudiness may be yeast being carried back into suspension by the CO2.
I am set to bottle in about 3 more weeks. Should I expect this to clear up by then? I have not seen anything similar with my other batches. Is this normal? I have another fermenter right beside that one with a Baltic porter that was not affected at all.
The off gassing should end fairly soon if the temperature remains the same. Your beer will begin to clear as soon as the CO2 is no longer present. This will happen to most beers when there is a temperature increase. The effect is just more readily visible in the lighter colored beers.
Check your gravity. If the specific gravity isn’t going down, the beer isn’t fermenting, it’s just CO2 coming out of solution.
“Flat” beer contains up to one full volume of dissolved CO2. Gasses become less soluble as the solution temperature increases, so the temperature increase could definitely account for bubbling in your airlock. Agitation will also create bubbling, as new liquid/gas solution comes into contact with nucleation sites inside your fermentation vessel (like dried krausen.)