Curing salts are the nitrite- and nitrate-containing salts used to cure meat — the chemicals behind the pink colour, characteristic flavour, and safety of ham, bacon, salami, and hot dogs. Sodium nitrite reacts with the meat pigment myoglobin to form nitrosomyoglobin, which heat then fixes as the stable pink nitrosohemochrome; just as important, nitrite suppresses Clostridium botulinum, the bacterium behind botulism. Because pure nitrite is toxic at high doses, it is sold diluted with common salt — Prague powder or pink salt — so the cure can be weighed accurately. Regulations cap the ingoing and residual amounts strictly, since excess nitrite can form nitrosamines during high-heat cooking. Used within those limits, curing salts remain one of the oldest and most effective hurdles in meat preservation.