WHAT USE-BY AND BEST-BY REALLY MEAN
The Institute of Food Technologists has clarified what each means:
You should use the product by the date on the label. That said, the date is more of a quality indicator than a health indicator. Food consumed after the use-by date won't taste as good. Unless it is a very long time after the use-by date, chances are you won't get sick eating it.
This label is aimed at retailers, who should either sell the product by the date on the label or remove it from their shelves. But this does not mean the product is unsafe to eat after the sell-by date. Typically, one-third of a product's shelf-life remains after the sell-by date for the consumer to use at home.
This is a suggestion to the consumer on which date the product should be consumed to assure for ideal quality.
Bottom line: Be smart. Use your sense of smell to determine if a food is safe to eat. If in doubt, throw it out.