So my 2L starter has been going for 24 hours roughly. I'm planning on brewing tomorrow. The starter was a bit slow to "start" but is now going pretty well, letting off a lot of bubbles on my stir plate. I want to decant the spent wort, however, given my timeline I need to decide to refrigerate tonight and let it sit in the refrigerator for ~24 hours, or do I let it ferment out over night and stick it in for ~12 hours before decanting? Its Wyeast 1272, medium flocculation.
One note, according to the video below (11:15 minutes in) when Wyeast spoke on Northern Brewer's channel, he actually mentions its ideal to "not let your starter hit terminal gravity" before pitching or refrigerating. This makes me lean towards refigerating tonight, but I thought I'd ask.
Worst case refrigerating tonight, I won't get the same growth but more yeast will flocculate. Worst case if I refrigerate tomorrow, I throw out some of the less flocculant yeast...
Another from Wyeast, Greg Doss, their microbiologist recommending never let it ferment over 18-24 hours or you'll stress out the yeast, i.e. "it's done." I think I recall there being different "stages" of fermentation and I'd imagine the idea of a starter is to finish the reproduction stage and halt... Greg also mentions leaving it warm and exposed to air, etc, that "it's gonna be hurtin' by the time you throw it in your beer."
Skip to 0:55 to find the relevant portion to this post.