canning

Food preservation method in which a cooked or uncooked food is sealed in a tin plated and lacquered steel can sterilized by heat treatment, sometimes under high pressure. The temperature required for effective sterilization varies with the pH of the item, and is generally higher than boiling point of water (100°C or 212°F) for low-pH foods such as fish (and other seafood), meats, poultry, mushrooms, and vegetables (except tomatoes). Practice of canning predates the discovery of disease causing bacteria (such as clostridium botulinum).