Starter question...timing

I pitched a 1.5L ale starter Saturday morning.  I’m using a stir plate (first time).  Will it be ready to pitch Monday afternoon?  I’ve heard 12-18 hours.  Is this correct?  I was hoping to refrigerate it Sunday night to drop the yeast out of suspension, then pull it out again Monday morning to warm up before pitching.

Depends on how fast the starter takes off.  If the viability was good and you can see activity at this point, then yeah, it’ll probably be fine to pop it in the fridge tonight.

I’d say maybe.

According to my yeast calculator, the viability was around 70%.  I assume the yeast calculator may err on the side of being too conservative.  Anyway, there was foaming/activity Saturday evening, and not much that I can see at 10AM Sunday.

By the way, how do you tell if there is activity when using a stir plate since there won’t be a mini-krauesen?  I assume the surface foaming was the activity since it is gone today.

My starters usually generate a pretty good layer of foam even with the stirplate going.

Do you use Fermcap in your starter?  I can’t recall seeing any foam on the stirplate.

Yeah, I do use fermcap.  But during the most vigorous part of the starter’s fermentation there’s generally still some foam there for me.

When using a stir plate, I’ve noticed that the starter goes from mostly transparent to milky within 12 hours or so, then after 24-36 hours I start to see chunks (floc) swirling around telling me the party’s over and it’s time to crash.

Letting it ferm out for at least 36 if not 48 hours lets the energy stores build back up in the yeast cells making for a healthier pitch come brew day. Remember; it’s not the total number of cells that matters most, it’s the health of those cells that will make for a happy fermentation.

i agree with “philm63”. Thats the way i do it normally 18 to 24 hrs. Then i crash it for a few days and decant then pitch. It takes about 1 to 2 days to crash.

Are there any problems with just pitching the entire starter into the wort?

I just started doing starters and I didn’t know about the cold crashing step.  I pitched the whole thing in after 24-36 hours.  I am using a stir plate and making roughly 1L starters.

Problem?  Not necessarily.

It just depends on the starter - is it fermenting warm?  Is it low gravity and throwing off the OG of your beer?  How does it taste?  Do you want it in your beer?

I’m a fan of cold crashing and then re-suspending it in some first runnings, but there is no right way to do it.