If you’ve cleaned out your pantry and found yourself tossing outdated cans of food, you may have screeched to a halt as another soup can hit the recycling bin, and wondered: Didn’t canned foods used to last forever? Why do they have expiration dates?
When cans display calendar dates—also known as “open dates,” to differentiate them from coded dates that only the manufacturer can decipher—they’re usually “best if used by (or before)” dates. They indicate the time by which the maker advises eating the food for best flavor or quality. They’re not safety-related.
Does that mean you can crank open a can of peaches that’s years past its prime? If the can isn’t bulging (which could indicate dangerous bacterial growth) or damaged, the contents might be safe to eat. But don’t expect old items to taste super-fresh. In general, high-acid canned foods such as tomatoes and pineapple will retain peak quality on the shelf for 12 to 18 months if stored in a clean, cool, dry place, according to the Department of Agriculture. Low-acid canned foods such as meat (Spam, anyone?), poultry, fish, and most vegetables will retain best quality for two to five years.
Even though the dates on cans are more about quality than safety, we were hard-pressed to find a company that endorsed eating outdated versions of their goods. When we asked whether it would be safe to eat a 10-year-old can of Chef Boyardee spaghetti and meatballs that had been stored in a cool pantry or basement, a rep for ConAgra, makers of Chef Boyardee and other brands, was blunt: “We do not recommend you consume this product.” Reps for Hormel (which makes Spam) and General Mills (Green Giant, Progresso) gave similar advice about their canned foods.