I hate to revive a 6 month old thread but wish I had found this yesterday. I have been building up a bank of about 9 different strains using the Iso alchohol freezing method glycerine storage solution using ~5ml slurry to 10ml glycerine solution. I have finally decided to start using one of them. I searched for a few days trying to find the method to build from a frozen sample but out of everything I searched, I couldn't find anything. The only article I found was from a different source where it indicated to thaw to around 80 degrees as quickly as possible then pitch like normal (1.036-1.04, 1l). I knew this sounded odd for two reasons; one to defrost this quickly didn't seem right (but I am an analyst, not biologist, so not sure), and the other that when you work with a small sample, you start with a lower volume of wort and lower gravity. In either case, knowing I had another 10 vials of this strain, I took a chance and used 3 tubes (15ml of slurry with the 30ml of glycerine solution), dropped in a container of water to bring to around 70 degrees, then pitched in 1l of 1.036. This was around 6p yesterday. This morning, it had a good krausen, smells normal, typical creamy color, and have a small amount of yeast settling once I took it off of the stirplate.
If I'm reading this thread correctly; you guys are doing
Slowly bring tubes from frozen state to room temp over 1-4 days (each person's method slightly different). When pitching frozen culture, pitch all of contents (slurry and glycerine).
Stepping Method:
- 750-1000ml of 1.02, then either crash/decant or simply add to step 2
- Step to 1.5l of 1.02, then crash/decant
- For the third step, treat like a normal starter as if it was a fresh pack of yeast, or did I miss something somewhere?
Does anyone feel that there is more value in a longer warming period (days) versus hours? I would think it is less stress on the cells, but again, I don't know either.
I'm probably going to start another iteration using the new method, as well as keep the original starter going to compare the differences.