What Do Those "Best By" Dates On Your Food Mean?

Seemingly, not as much as you think:

Avoiding unseen food hazards is the reason people often check the dates on food packaging. And printed with the month and year is often one of a dizzying array of phrases: "best by," "use by," "best if used before," "best if used by," "guaranteed fresh until," "freeze by" and even a "born on" label applied to some beer.

People think of them as expiration dates, or the date at which a food should go in the trash. But the dates have little to do with when food expires, or becomes less safe to eat. I am a microbiologist and public health researcher, and I have used molecular epidemiology to study the spread of bacteria in food.

A more science-based product dating system could make it easier for people to differentiate foods they can safely eat from those that could be hazardous...

The dates on those food packages, however, are not regulated by the Food and Drug Administration. Rather, they come from food producers. And they may not be based on food safety science.

For example, a food producer may survey consumers in a focus group to pick a "use by" date that is six months after the product was produced because 60% of the focus group no longer liked the taste. Smaller manufacturers of a similar food might play copycat and put the same date on their product.

One industry group, the Food Marketing Institute and Grocery Manufacturers Association, suggests that its members mark food "best if used by" to indicate how long the food is safe to eat, and "use by" to indicate when food becomes unsafe.

But using these more nuanced marks is voluntary. And although the recommendation is motivated by a desire to cut down on food waste, it is not yet clear if this recommended change has had any impact.

A joint study by the Harvard Food Law and Policy Clinic and the National Resources Defense Council recommends the elimination of dates aimed at consumers, citing potential confusion and waste.

Much more information at the link.