c0bra
Well-Known Member
I followed FlyGuy's instructions here: https://www.homebrewtalk.com/f13/guide-making-frozen-yeast-bank-35891/ recently and whipped up 10 vials of WY1056.
Everything seemed to go well but the next day I noticed that the contents of the vials had not frozen. I had them in a smaller cooler with ice packs as suggested, so I left the door on it open thinking it might have insulated them from the cold a bit (this is a manual-defrost freezer, so no freeze/thaw temp cycles). Several days later they're still not frozen, though some have frozen bits or slush.
What's the deal here? I tried to use about 15% glycerine (which I picked up at the LHBS) but I didn't measure and it might have been more like 25%. Could that have lowered the freezing point? I should note that this freezer has frozen several gallon jugs of water solid overnight. Will the yeast be okay, if they're at a low enough temp, or am I screwed?
TIA
Everything seemed to go well but the next day I noticed that the contents of the vials had not frozen. I had them in a smaller cooler with ice packs as suggested, so I left the door on it open thinking it might have insulated them from the cold a bit (this is a manual-defrost freezer, so no freeze/thaw temp cycles). Several days later they're still not frozen, though some have frozen bits or slush.
What's the deal here? I tried to use about 15% glycerine (which I picked up at the LHBS) but I didn't measure and it might have been more like 25%. Could that have lowered the freezing point? I should note that this freezer has frozen several gallon jugs of water solid overnight. Will the yeast be okay, if they're at a low enough temp, or am I screwed?
TIA