The secret to a can’s remarkable lifespan lies in the preservation process. Canned food is cooked inside its sealed container at high temperatures, killing bacteria and creating a vacuum that prevents new microorganisms from entering. As long as that seal remains intact, the food is protected from spoilage and contamination.
Storage conditions are what truly determine how long canned goods last. A can kept in a cool, dry, dark place — ideally below 85°F (29°C) — can outlast its label by years. Heat and humidity are the real enemies. They can corrode the metal, compromise the seal, and slowly degrade the food inside.
Different types of canned foods age differently:
High-acid foods (like tomatoes, tomato sauce, pineapple, or citrus fruits) last around 12–18 months. Their natural acidity helps inhibit bacteria but can gradually wear down the can’s lining.