Experts weigh in on food safety after ‘best before’ date passes


Published January 19, 2024 at 8:37 am

As Loblaws moves to reduce its 50 per cent discount on food approaching its best before date to the more modest 30 per cent, experts say those time stamps aren’t an accurate measure of whether groceries are safe to eat.

Very few food items have true “expiry” or “use-by” dates printed on their labels, say food safety professors. The more common “best before” dates just indicate when food is at its peak freshness — in other words, when it tastes the best. Some food is safe for weeks or months (and in some cases years), regardless of what the packaging says, while other products may go bad before the best before date passes.

Instead of relying on the label, experts say, pay attention to when a product was opened and use your judgment to determine if it’s gone bad.

“If it’s been unopened, for many products you can open the product and safely eat it after the best before,” said Ian Young, a food safety professor at Toronto Metropolitan University.

“But regardless of the best before date, once that product has been opened and unsealed, then you should probably eat it within three or four days, depending on the product specifically.”

Keith Warriner, who teaches food safety at the University of Guelph, said the senses are another valuable tool in determining if something’s still edible.

“I’ve evolved with these senses for what’s good food and bad food and which we can use,” he said. Bad smells, strange new textures, and in some cases patches of mould are all indicators to toss your old groceries in the compost bin.

Here are some general guidelines Warriner and Young shared on how to know if your food has spoiled:


Non-perishables such as canned goods and dried pasta will keep for years if they remain unopened, Young said. Those canned tomatoes may not taste quite so fresh after a decade, but generally they won’t be unsafe to eat.

Has your garlic or ginger dried out? Not to worry, said Warriner. The flavour may not be as rich, but it’s certainly not a health risk.

If there’s mould on your hard cheese, it’s fine to cut around it, he said. About an inch away from the mouldy patch on all sides should do the trick.


Other dairy products like soft cheeses and yogurt should be thrown away if they get mouldy. If you’re opening a fresh yogurt container that’s past its best by date and it doesn’t have signs of mould but there’s a layer of separated fluid on top, that’s not cause for concern, said Warriner. Give it a stir, and then try the sniff test.

It may not sound like fun, but if the sniff test is inconclusive, the experts say taking a little taste of yogurt past its best before date is also fine.

Young noted that cantaloupe has been top of mind due to a deadly salmonella outbreak first linked to the melon in November. Sixty-one people across Canada were hospitalized, and seven died.

Melon can be a tricky case, Young said, because unlike most other fruits, its pH is neutral. It doesn’t have the acidic properties that make other fruits inhospitable to pathogens.

“It’s basically like leaving chicken out,” he said.

Cut melon should be refrigerated at all times, Young said — particularly if it’s been pre-cut. Opportunities for cross contamination are rampant.


While shrivelled garlic is no cause for concern, people hoping to “preserve” the allium in oil should be wary.

“It looks good on the shelf, but it can be deadly,” Warriner said. Clostridium botulinum is a pathogen that’s in the soil and can be on garlic. If garlic is kept at room temperature in oil, it offers a perfect breeding ground for that pathogen, which causes botulism.

Both raw and cooked meats and fish should also be tossed if they haven’t been eaten within a few days of refrigeration, Warriner said, and so should deli meat.

This report by The Canadian Press was first published Jan. 18, 2024.

Nicole Thompson, The Canadian Press