« on: May 08, 2011, 08:50:14 PM »
On stirplate for 24hrs, then into frig over night, pulled out and decanted a few hours before pitching.
This procedure doesn't seem quite right to me.
If I have a 24 hour-old starter, I pitch the whole thing.
At 24 hours, that starter is probably at or near its highest level of activity. Shocking the yeast in this state by chilling the starter is not good for the health of the yeast, I would imagine.
If you want to decant the starter beer and pitch the yeast slurrry, my understanding is that it is best to let the starter run for several days (4-7) to allow the yeast to build up nutrient reserves, and _then_ chill to force them to floc.
I can't say why _exactly_ what you are doing is causing that result, but I would suggest you change your procedure and see if that helps.