mason jars are opened for short periods only during the cure (and removing whatever is needed for the bowl)...other than that there's no need to do it afterwards. i keep mine stored in jars in the fridge and have never had mold probs...but i have gotten mold in jars when kept outside the fridge too long before the cure finished (iow, it was still a bit moist and the closed jar only added to the mold prob).

to sum it up...i suggest storing in canning jars, inside the fridge after the cure is finished.