An expiration date is a guide to the consumer stating the last date that a food item can be consumed before it is considered spoiled. This date is usually expressed on the food item's label. The Food and Drug Administration has no specific guidelines for food apart from baby formula.
The Food and Drug Administration only requires best before and expiration labels on baby formula, according to Pallavi Gogoi in a "Business Week" article from October 2006. Baby formula is required to contain a specific quantity of certain nutrients as indicated on the label. Once baby formula has been stored for a certain amount of time, the nutritional value decreases and the formula can clump together, blocking the baby bottle nipple.
There is no official system for food labeling which is accepted all over the United states, according to the United States Department of Agriculture. Food dating in general is not required by federal law, however, in almost 20 states across America, some sort of open date labeling is required. In others, almost no food is labeled with expiration dates.
Expiration and best before labels are not meant to be absolute rules on when to throw food away, University of Georgia food science professor, Mark Harrison, told "Business Week." Many times, the dates are an indicator of quality rather than safety. The expiration dates are only meant as rough guides. If you eat something that is just past its sell by date, it is hardly likely to do you much harm.