Food safety Margins

What Food 'Sell-By' Dates Really Mean
Suzanne Havala Hobbs, DrPH, RD
University of North Carolina at Chapel Hill any states require food manufacturers to mark perishable foods with a date so that customers can gauge product freshness -- but since there are no federal regulations requiring products to be dated, there isn't a uniform system. Here is a guide to the most common terms and what they really mean...
"Sell-by" dates let stores know how long products can remain on the shelves. They also are used as guides for rotating stock. The sell-by date takes into consideration the length of time a product typically sits on the shelf at home after purchase. Perishable foods remain good for a period of time after the sell-by dates, assuming that they have been stored properly. Use your eyes and nose to judge product freshness. For example, milk, cheese and yogurt that smell sour or have turned color should be thrown out.
General guidelines for shelf life beyond sell-by dates...
Eggs usually are good for three to five weeks past the sell-by date.
Milk typically is good for up to seven days past the sell-by date.
Fresh chicken and turkey should be cooked or frozen within two days after the date.
Fresh beef, pork and lamb should be cooked or frozen within three to five days after the date.
Ground meats should be cooked or frozen within two days of the date.
Unopened processed meats, such as bacon, hot dogs and luncheon meats, should be used within two weeks after the sell-by date.
Unopened canned meats, such as tuna and sardines, will keep for about two years beyond the sell-by date.
"Best if used by" and "use by" dates refer to the point after which peak quality -- flavor or texture -- begins to decline. These are not safety or purchase dates.
Caution: Shelf life depends upon handling and storage conditions. Fresh perishable foods should be kept at 38°F to 40°F for maximum safety and quality.