First, it is important to note that cheese has living organisms within, so it needs to be stored appropriately. Don't try to wrap leftover cheese in plastic wrap — it hates that! Ideally, you should wrap your cheeses in cheese paper. If you can't find any, parchment or wax paper will do the trick. Once wrapped, you can place it in a plastic bag. Fresh, young cotija can last for up to a month if properly stored. Aged cotija can last for up to 3 months.