Sodium nitrite is used to speed up the curing of meat, inhibit the germination of botulism spores, and impart an attractive pink color. [7][8][9] The color change is caused by the reaction of nitrite with myoglobin, first to nitrosomyoglobin (bright red) and then to nitrosohemoglobin (a pink pigment). [10]
Historically, salt has been used to preserve meat. Salted meat products are usually brown-gray in color. When sodium nitrite is added with salt, the meat turns red and then pink, which is associated with cured meats like ham, bacon, hot dogs, and bolognese. [11]
In the early 1900's, irregular curing was common. This has led to further research around sodium nitrite as a food additive, standardizing the amount present in foods to minimize the amount needed while maximizing its food additive effect. [12] Through this study, sodium nitrite was found to impart flavor and color to meat and to inhibit lipid oxidation that leads to rancidity, with varying degrees of effectiveness in controlling the growth of pathogenic microorganisms. [12] Sodium nitrite's ability to address the above issues resulted in the production of meat with extended shelf life and improved desirable color and taste. According to scientists in the meat industry,[13] nitrites improve food safety. [12] This view is controversial given the possible carcinogenic effects of adding nitrite to meat.