Creatine degrades in liquid quickly, depending on the temperature of the liquid--the hotter, the quicker.
http://www.gain-weight-muscle-fast.com/ has more info on
creatine than you could ever want. I learned a lot about how to take it from there. They actually recommend disolving
creatine in hot water before taking it.
I wouldn't give it any more than 10 minutes before consuming.
I haven’t heard anything about proteins degrading. I'd imagine they're pretty stable. In my experience, the longer you let
BCAA sit in liquid (especially acidic juices), the better it disolves, which means fewer clumps.