Originally Posted by Shmohel
You just store it in a refrigerator? About how long will it last?
A bit more detailed and I'd review this
link. Homebrewer_99 had a nice writeup. I don't take it quite to the anal levels I've seen in some instructions but I do make sure everything is "really" sanitized (actually, no more than any other brew process). I also do perform an isopropyl alchohol wipe and light on the top of the bottle that I'm saving it in. I'll "burp" the bottles often. For instance this last save yesterday I burped the bottles in the fridge about 2 hours later (1/2 full with slurry). They had huge pressure since it was still active while getting cold. Then burp daily for a week, then 2 times a week or so afterward.
Not sure how long they'll last and I don't take chances but have gone 3 months. What you should do (must?) is do a starter with your saved slurry to make sure it's good and smells "normal".
I tend to brew appropiate recipes for what I have on hand to use it up. I had 3 bottles of wl british ale yeast slurry so I did an IPA and a english style pale ale with those two bottles & will use the 3rd for more IPA. I didn't save slurry from these subsequent batches as I want to move on from this yeast & styles of beer but with my one vial I made 4 batches of brew. With this Belgium Wit I saved off, I'll just keep making that style of beer, trying to perfect my spin on the recipe (all grain here).