[flbrewer]

I need some clarification on when to cold crash a starter please. I believe in the past people have mentioned after the krausen begins to fall. I have read more recently that you should crash after fermentation is over in the starter. Thoughts? Bonus picture below of my starter after 18 or so hours.

[JT]

This answer, like many others, depends on who you ask.  I had planned on dosing my next starter with oxygen, shaking and then crashing at high krausen.  Previously I've done 18-24 hours on a stir plate, with no oxygen injection.  What yeast are you using?

[gmac]

I am sure I am wrong but I am happy with me results. I let mine ferment out and then cold crash. Decant the beer and pitch dregs. Now, if I forget to make a starter ahead or don't have time. Then I make a starter using wort and pitch the entire thing at high krausen but I am doing 15 gal batches so one litre of starter is of little concern to me.
That's what I do and it works for me.

[flbrewer]

What yeast are you using?

WLP 001

[JT]

The good news is it is hard to go wrong with that yeast for beers within normal gravity ranges.

[denny]

I am sure I am wrong but I am happy with me results. I let mine ferment out and then cold crash. Decant the beer and pitch dregs.

Just what I do, too.

[brewinhard]

I too prefer to let my starter ferment to completion before cold crashing (usually around 24 hrs is enough depending on starter size and yeast freshness).  All starters done on a stir plate.

[Stevie]

Now, if I forget to make a starter ahead or don't have time. Then I make a starter using wort and pitch the entire thing at high krausen...

I have been reserving this in my toolbox for a while. Such a smart and easy trick.

[klickitat jim]

Unless I'm pitching at high krausen I chill after the growth phase.

[bassetman]

After the cold crash when is the best time to use the starter and how long could you delay in a pinch?

[rjharper]

Now, if I forget to make a starter ahead or don't have time. Then I make a starter using wort and pitch the entire thing at high krausen...

I have been reserving this in my toolbox for a while. Such a smart and easy trick.

I've done this a few times. Quite frankly, it's tempting to make this my normal practice.

[gmac]

After the cold crash when is the best time to use the starter and how long could you delay in a pinch?

If I plan to brew Friday then I crash Thursday night and pitch the next day. I have had pitches wait 3 or 4 days with no issue but if things change and I can't brew for a week or so then I pull a bit of boiling wort in a clean mason jar, cap and cool and then put it on the yeast cake and pitch the whole thing a couple hours later. But I have only had to do this a couple times. Mostly I think it just wakes the yeast up.

[flbrewer]

OK, to beat a dead horse...I'd really like to brew tomorrow, but the starter is still chugging along. The krausen has fallen considerably but there is still active fermentation.

Would cold crashing tonight for 12 or so hours and decanting be "throwing away" some of the potential active yeast vs. waiting for fermentation to fully finish?

[gmac]

I believe that if the krausen has fallen then the yeast are now just building up resources and not reproducing. I believe you will be just fine to crash it tonight and then brew with it tomorrow. I certainly would.

[S. cerevisiae]

Unless we are talking about a huge starter, crashing isn't really necessary.  I almost never crash my starters.  I pitch the entire contents of the starter vessel.  However, then again, I do not use a yeast stress inducing stir plate.