Nitrite
Nitrite is the NO₂⁻ ion, used in meat curing to inhibit certain microbes and help develop cured-meat color and flavor.
Nitric oxide: Nitric oxide is a small signaling molecule and reactive nitrogen compound with the formula NO. Nitrite-derived nitric oxide binds myoglobin, producing the pigment that gives cured meat its pink color.
Curing (food preservation): Curing is the preservation of food using salt, nitrite, nitrate, smoke, or combinations of these methods. Nitrite is one of the agents that gives cured meat microbial protection and its characteristic qualities.
Dietary nitrite: Dietary nitrite is nitrite consumed in food or formed in the body from other compounds. Cured meat is one source, but vegetables and internal nitrate metabolism also contribute to exposure.
Nitrogen oxides: Nitrogen oxides are compounds made from nitrogen and oxygen, including nitrite, nitrate, nitric oxide, and nitrogen dioxide. Nitrite belongs to this broader chemical family but has distinct food-curing reactions.
Myoglobin: Myoglobin is an oxygen-binding protein that stores oxygen in muscle and contributes to meat color. Nitrite-derived nitric oxide changes myoglobin into the stable pigment associated with cured meat.
Cured meat: Cured meat is meat preserved or flavored with salt, nitrite, nitrate, smoking, or related treatments. It is the main food category in which nitrite is deliberately added.
Processed meat and cancer: Processed meat is classified as carcinogenic to humans by the International Agency for Research on Cancer, based on evidence linking consumption to colorectal cancer. Nitrite is one feature of some processed meats, but the cancer classification applies to processed meat as a whole.
Anion: An anion is an ion with a net negative electric charge. Nitrite carries a single negative charge, which shapes its behavior in aqueous solutions and salts.
Nitrate: Nitrate is the NO₃⁻ ion, found in foods and used in some curing processes. Unlike nitrate, nitrite can directly participate in reactions that inhibit microbes and alter meat pigments.
Bacon: Bacon is salt-cured pork, commonly made from the belly and often smoked. Many bacon products use nitrite to control microbes and develop their cured color and flavor.