But food technologist Gary Sandberg, who heads the Food Technology Program at BCIT, said while some items may not taste as fresh after the best before date, they could still be safe to eat.
"The biggest issue is that if you're paying full price for something that has an inferior quality, that's where the challenge comes in," said Sandberg, who also oversees food safety and processing at farmers markets for the BC Centre for Disease Control.
Any pre-packaged food with a shelf life of 90 days or less is required by law to have a best before date stamped on the package to let customers know when it is at its freshest, but many of those foods can still safely be consumed after that date.
The best before date indicates freshness and is different from expiry dates.
Expiry dates are required on foods like baby formula and nutritional supplements and indicates the date after which the food will not live up to the nutritional promises on the label.
The Canadian Food Inspection Agency says food with an expiry date shouldn't be consumed after that date, but Sandburg said most food products are still safe to eat after the best before date — as long as they haven't been opened and exposed to outside contamination.
"A lot of those products, if they're still in their package it's going to be quality changes that they're going to suffer from more than any food safety risk," said Sandberg.
Here are three foods Sandberg says can be eaten after the best before date — and the reasons you may want to toss them out anyway.
1. Ketchups and salsas
We've all found a bottle of ketchup or tub of salsa at the back of our fridges and cupboards and Sandberg they are still edible past the best before date.
But he said foods like ketchup and salsa will tend to get more acidic, and will taste more sour or bitter after the best before date has passed.
2. Dry pasta
Pasta can still safely be eaten pas the best before date, as long as the box stays dry, but Sandberg said the older it gets the less you'll want to eat it.
"As long as there's no gain in moisture, then they're going to have a tendency to just dry out more and then, in the case of pasta, it's just going to fall apart when you cook it," he said.
If cheese stays in its package and doesn't get contaminated by outside moulds, it will develop stronger flavours.
"If it's in the package and the mould starts to grow, chances are that's related to the moulds and the ripening," said Sandberg.
"But once you open a package — just the environment around you — the product becomes contaminated and moulds for example can look very similar, even if they're a totally different species and that's where the risk starts to come in."
To hear the full interview with Gary Sandberg, click the audio labelled: Food technologist Gary Sandberg on best before dates.
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