Linuxboy, I boil everything before making my culture and I don't open after taking out of cooler until time to use. Does freezing the starter in the plastic cup destroy it? I was really asking if I can keep it going by always using the frozen plastic cup full to make a new batch instead of using the dvi again.
Farmer, freezing doesn't destroy all culture. Some of it dies off, though. I can't say how much because it depends on the speed with which it was frozen and the temp at which it's held. If you freeze very very quickly, the ice crystals are small, and when you slowly defrost, more cells are viable. Freezing slowly or large volumes gives the large ice crystals a chance to form, and this physically ruptures cell membranes. Using a small container also helps.
You should be ok reculturing from the plastic cup. If you want to stay on the safe side, you could reculture 3-5 times, and then make a fresh batch from the powder. Or make up 2-3 plastic cups from the original and use them up.
One detail I was to mention is that when you reculture multi-strain DVI products, future generations will not be identical to the powder in terms of the ratio of the sub components. I'm not sure what ratio of lactis and cremoris is used for Meso 11, but in the lab, the strains are kept separate and then combined according to the internal proprietary recipe. Practically, this means that you will not get a strictly identical cheese with recultured DVI starters. Of course, that doesn't matter much to us because producing exactly identical cheeses is just about impossible at home. It'll still taste good if you reuse the frozen sample and your kids will still eat the cheese