Grated cheese you can buy in the store (just in a bag so), but possibly also homemade, go moldy very quickly if you just keep it in the refrigerator, it is my experience. Have been many half arrived, turned green bag to throw away, a waste of money! But now that I recently received a good tip, viz. The bag in the freezer / freezer rather than refrigerate. The cheese is a bit frozen, but if you do it on hot food is so resolved and it remains just pourable. Ideal!