Just brewed a fat tire clone from AHS. I rehydrated the dry nottingham yeast, and added a little wort to get the yeast to the same temp as the wort per the yeast instructions. i noticed when I pitched the yeast, they had a sour smell, almost like a sour dough bread. Is this normal? Everything was well sterlized (I think), so I'm not too worried, just didn't notice this wih my last yeast package (which was a dry wheat yeast, but don't remember the exact name and don't have my notes handy).