After opening a can of tomato sauce, if you can't eat it all at once, it will go bad easily after a period of time. If you open the can of ketchup a mouth, first into the pot steamed and then eat, the leftover tomato sauce can be in a longer period of time not bad. Preventing ketchup from spoiling is another outside - a good way, that is, in the opening of the tomato sauce can put a layer of plastic film seal, into the refrigerator layer can also be stored.
