Those sudden bubbles when you crack open canned tomatoes are often nothing more than dissolved gases escaping as the pressure is released. If the tomatoes look bright, the liquid is clear, and the bubbles vanish quickly, they’re usually safe to use. A normal tomato scent—acidic, fresh, and clean—is your first reassurance that what you’re seeing is a harmless side effect of canning, not a health threat.
Concern begins when the bubbles turn to foam, linger on the surface, or come with cloudy liquid, odd colors, or mushy, slimy pieces. Sour, rotten, or yeasty smells are strong warnings; a bulging, rusted, or badly dented can should never be opened at all. In every case of doubt, the rule is simple and non-negotiable: do not taste, do not “test,” just throw it away. Your health is worth more than any can in your cupboard.
