We have a choice of one “ultrafiltered” brand and a couple of others that are not. The ultrafiltered one has an expiration of a month or more, while the other is more like 3 weeks. Although I do not understand what is going on, only the ordinary milk can be used for cheese (I make a kind of mozzarella, also ricotta, although the latter could probably be made from the ultrafiltered milk; I haven’t tried it.