It doesn’t help the image of dairy when consumers open a container of milk to find that it has spoiled. Unfortunately, some grocery stores carry dairy products longer than their intended expiration dates.

In a University of Southern California study, at least one expired dairy product was found in about one-third of the visits made to grocery stores and supermarket chains in lower-income areas of Los Angeles.

Data for expired items ranged from 19.2 percent to 39.5 percent (of the visits) for poultry, 20 to 41.8 percent for beef and 26 percent to 45.4 percent for milk and dairy products.

Read "Markets Selling Expired Food."

Source: Monsanto and The Lempert Report