1 Unopened processed meats, such as bacon, hot dogs and luncheon meats, should be used within two weeks after the sell-by date. 2  Unopened canned meats, such as tuna and sardines, will keep for about two years beyond the sell-by date.eneral guidelines for shelf life beyond sell-by dates: 1  Eggs usually are good for three to five weeks past the sell-by date. 2  Milk typically is good for up to seven days past the sell-by date.