remilard wrote:Well yeah, freezing would be great. For most of us the easiest method of storing yeast cultures frozen is to let a vendor do it for us.
I would expect the same yeast growth in a stab and a slant, but still think the lack of air exposure in the former is advantageous. Perhaps the advantage is so marginal over slants to render the practice practically useless.
I agree that getting from the vendor is easier than freezing and that stabs are slightly better than slants. I was only suggesting that freezing a glycerol stock is an option, and that it's not very difficult (even if you don't have access to a -80). Just make your glycerol stock when you streak your first set of slants and throw it in the freezer and maintain your slants as you normally would. I guess if I were storing in a -20 freezer I would propogate and refreeze every 12-18 months just to be safe. I would also store them in an insulated container like a small styrofoam chest if you have a frost-free freezer (as you should do for your hops) to protect them during the thaw cycle. I also like glycerol stocks as a way to recover the original strain if the slants/stabs mutate or become infected over multiple passages. Just pull the master stock out and start over.