Originally Posted by SGT-RIEL
What I'm getting at, is buying a pitchable vial of yeast and culturing it further into more pitchable vials for use 6 months to a year from now.
That is not commonly done so I don't think there will be much literature on it.
Normally pure cultures are saved for reuse by culturing them on media, storing them cooled (or frozen), then stepping the back up to pitchable size.
If you wanted to go for it, here are my first thoughts on a possible procedure:
(in oven, autoclave, or pressure canner) everything but the yeast: flask, foil, funnels, whatever. I'd have the starter+nutrient in the flask already and sterilze in situ
. Allow to cool.*
2. Pitch yeast into flask of starter, preferably on a stirplate.
3. Allow it to run long enough that you are convinced there are no fermentables left.
some bottles and funnel, sanitize caps. Based on my unscientific testing the White Labs vials also survive pressure sterilization and will still seal, although some of the flanges warp. I think we are going to want more volume than a vial, though, unless you can achieve massive starter density in step 3.
5. pour the maxxed out starter into the bottles, cap**
6. store in fridge (preferably inside a bin in case there are contaminants or residual sugars and they BTFU) until use.***
7. I'd still pitch these into starters instead of into the primary, but then again I generally do not consider vials/packs directly pitchable anyhow.
* I love pressure canners for this. I recently bought a taller canner that allows me to sterilize even my biggest flasks standing up with the foil caps in place.
** yes, I know that capping will be controversial. But I think that if the OP is storing a half-dozen bottles of "pitchable" starter in the fridge caps are more practical.
*** Mr. Safety would suggest wearing eye and hand protection in case of overpressured