NOCs have been detected in foods processed by smoking
or direct fire-drying, which uses sufficient heat to oxidize
molecular nitrogen to nitrogen oxides, which are able to
nitrosate amines present in foods such as meat [Mirvish,
1995]. NOCs are also formed in meats containing nitrite,
which is added as an anti-bacterial agent against
Clostridium botulinum and as a cosmetic agent to react with myo-
globin and produce the characteristic red-pink color of
cured meats. When nitrite is in acidic conditions such as
those found in food processing operations, dinitrogen-, tri-
and tetraoxides can form, and these are potent nitrosating
agents. In an attempt to reduce the formation of NOCs under
these conditions, it has become customary to add ascorbic
acid to such processing procedures. Ascorbic acid scav-
enges nitrosating agents and can therefore reduce N-nitro-
sation reactions [Ohshima and Bartsch, 1981]. Daily NOC
intake from dietary sources has been estimated to be 36–
140g, with bacon and beer being the main sources
[Gangolli et al., 1994]
Source:
http://onlinelibrary.wiley.com/doi/10.1002/em.20030/pdf