I added 6 lbs. of blueberries to a wheat beer secondary that had been in the primary for a month. Should I expect some fermentation to occur? I was expecting something, nothing too rapid but after watching the airlock for a few minutes after 24 hours I didn’t see anything.
What kind of fruit? In other words, are the sugars readily available to the remainder of the yeast? If you just dumped fresh/frozen fruit in, it will take some time for the sugars exit the fruit.
Canned puree? After a month it may take some time for the yeast to wake up and go to work.
Did you try to do a clean transfer or did you try to bring some extra yeast with the transfer?
You should definately expect some additional fermentation to occur, but it may not be very active and it may take quite a long time to complete. If you just dumped in whole blueberries, it will take time for the sugar to go into solution where it is readily available to the yeast. You may not notice any airlock activity.
If the blueberries were fresh or recently frozen (not bought from the supermarket frozen food section), there is a significant chance of bacteria being present on the fruit. Is so, it will take 2-3 weeks for them to finish up, souring the beer some in the process, but likely not ruining it.
I always wait a month after adding fresh fruit before I’ll risk bottling it.
I added 6 lbs. of frozen blueberries to 5 gallons of wheat.
Whole or crushed?
I pounded them in the bag a little bit before dumping them in to break them up a bit.