I want to save some Hefeweizen yeast in a preform (the thing White Labs) sells their yeast in. Can I just take some wort during fermentation and put it in the preform and chill it? Will this save me enough yeast? Is there something wrong with this incredibly simple procedure?
Where is yeast now?
If you pitched it you can wash it after racking/bottling, or do top cropping.
If it is still in vial you can make larger starter and estimate how many you can save and how many to pitch.
We are only 10,000 years into beer... there are thousands of years left to go!
Things are bound to change!!
I usually do the standard starter, cold crash, decant, then store the slurrey, step, cold crash decant both the starter and the tube, top off the tube with fresh slurrey and pitch the rest. I have no information regarding yeasts that may store better than others.
Yeah it does not store very well but if you use it very soon it could work.
It also looses it's characteristics if it's under pressure (like at the bottom of a big fermenter). So most brewers agree that it's best to top crop during high krausen. Maybe in a small homebrew fermenter it would not make much difference.