Let the Cooled Wort breathe after pitching?

[summitbear]

I have about 14 AG batches under my belt and I have never seen fermentation start in under 12 hours. Usually around 14-20 hours is my norm and this is fine. I do not add O2...just shake a lot. I decided to put on the plug and airlock minus the bobber so the cooled wort could pull in any O2 needed through the little holes in the airlock cap. The yeast must have been happy because they were partying 12 hours later. Does anyone else allow the cooled wort to breathe after pitching yeast or is this inviting problems? Breathing seems to have gotten the yeast active a couple of hours earlier than normal.

 

[Hermit]

Chris White in the "Yeast Book" suggest covering the carboy with aluminum foil until the krausen falls.

 

[eastoak]

I have about 14 AG batches under my belt and I have never seen fermentation start in under 12 hours. Usually around 14-20 hours is my norm and this is fine. I do not add O2...just shake a lot. I decided to put on the plug and airlock minus the bobber so the cooled wort could pull in any O2 needed through the little holes in the airlock cap. The yeast must have been happy because they were partying 12 hours later. Does anyone else allow the cooled wort to breathe after pitching yeast or is this inviting problems? Breathing seems to have gotten the yeast active a couple of hours earlier than normal.

or it could just be a coincidence, try the same thing with BRY-97 yeast and if they take off any faster than usual you would be on to something. i can't think of any reason why the yeast would react any way to an airlock being off or on.