This article originally appeared in Food in Canada and is republished with the permission of the publisher.

While much of the data on food labels is notoriously incomprehensible to the average consumer, at least "best before" and "packaging" dates are easy to understand and provide valuable information on food safety. Right? Wrong.

According to B.01.007 of the Food and Drug Regulations, when a pre-packaged product having a durable life of 90 days or less is packaged at a place other than the retail premises from which it is sold, the food's label must show the durable life date and provide instructions for proper storage conditions if it requires storage conditions that differ from normal room temperature. The durable life date is to be expressed on food labels as "best before date" using standardized bilingual symbols. So, for example, this June 15 would appear as 19 JN 15.

But now it gets a little confusing. Durable life is defined as "the period commencing on the day on which a pre-packaged product is packaged for retail sale during which the product, when stored under conditions appropriate to that product, will retain, without any appreciable deterioration, its normal wholesomeness, palatability, nutritional value and any other qualities claimed for it by the manufacturer." While it is true that "wholesomeness" is related to food safety, the durable life is more to do with food quality. There are no rules on how to establish durable life for products so this is a matter at the sole discretion of the manufacturer and the date is only valid for unopened products. Many foods could be unsafe within the best before date depending on how it has been stored and others perfectly safe for years after the best before date.

Even more confusing, if in the opinion of the manufacturer the shelf life exceeds 90 days, there is no requirement for any best before date. However, manufacturers now use them anyway for their own traceability purposes, so we have so-called best before dates on canned and other packaged products that can be safely on a shelf for years. Is it any wonder that a consumer is confused by a best before date on the bottom of a can that is five years away? This "information" says very little about quality and nothing about food safety.

There appears to be no standard or scientific basis for the determination of what is a durable date or shelf life for products. Foods prepared by a commissary and sold in automatic vending machines or mobile canteens and prepackaged salads and fresh fruit trays are exempt from the regulations, even though they have all been a recent source of foodborne illness.

Retail-packed products require a "packaging date" and there are definitional problems here as well. "Packaging date" means "the date on which food is packed for the first time in a package in which it will be offered for sale to a consumer." A roast, for example, can be packaged by a butcher with a packaging date and there is no labelling law that prevents the retailer from cutting up the roast later with a new date as stewing beef and then again later with a new date as ground beef. Your chicken shish kabob packaged yesterday may have been chicken breasts packaged last week, and no labelling law has been broken.

The issue has taken on new complexity with the growing concern about food waste. A recent report by the National Zero Waste Council says that confusing best before dates are a "major source of food waste in Canada" with the result that "Canadians are among the biggest food-wasters in the world." The Council is against removing products from shelves after the best before date. There is even now a thriving store chain in the U.K. called Affordable Foods that sells super- cheap food on or near its best before date. Whether consumers will be less confused by this or this movement has implications for food safety remains to be seen.

Follow storage and cooking instructions carefully and remember that best before and packaging dates do not provide reliable information on food safety.