Jim, thanks for joining us here in the thread.
I love what Enric does, totally support the approach. As an alternative, microbiologically speaking, freezing is not necessary. A culture stored at 35F will be stable in terms of viable CFU/g population density for ~96 hours. It does decline after this, but less so than the loss from freezing. Where freezing makes more sense is in terms of longer-term storage. There are also ways to extend that longevity to weeks at refrigeration temps, but that's more work.