SWIM just has a quick question. Should all the spice be dissolved in the solvent? When SWIM tried recrystallizing, he found that some yellow oily stuff formed on the bottom of the container as he was mixing in the spice; it only dissolved when more solvent was added. Should this oily stuff be dissolved too? From what I've read, it should separate again after cooling, but I want to be certain before telling SWIM anything.

As for the CO2 thing, it could be potentially dangerous unless there's maths behind the quantities... you don't want your container exploding from an excessive build-up of gasses.