yeast starter propagation help

[HomebrewPadawan]

I am trying to turn 1 vial of WLP001 into enough for approximately 3 vials: 2 will be used soon and the last 1 vial would be "banked." I am currently using the "shaking method" of aeration.

I added the 1 vial of WLP001 into a 2L 1040 wort and it has been propagating/fermenting for about 44 hours now. The yeast matter has certainly grown in size on the bottom of the glass. I intermittently shake/swirl at least 10x a day.

Based on pitch rate calculators I should have around 220-240 billion cells once the starter is finished; the plan from there was to crash the finished starter, decant, and then divide the slurry into three 8oz sanitized mason jars. This would give each jar approximately 73-80 billion cells. When I went to brew I would add one jar into a 1.5L starter for a batch of regular strength brew (for examples sake, say something like 1050) and be ready to pitch in 18-24 hours.

The question I have is when do I cold crash this starter? I have read the term "fermented out" and assume that means when all signs of fermentation have ceased.

Please help!

 

[flars]

Cold crash when all fermentation is complete. To tell when fermentation is complete let it sit undisturbed for two hours.
Then swirl it, not shake. If a small krausen appears it isn't done fermenting out. Give it a good shake to aerate and try again later.