transnitrosation of N-methylaniline by a protein-bound nitrite model system in relation to N-nitrosamine formation in cured meats

The reactions of sodium nitrite, S‐nitrosocysteine hydrochloride, S‐nitrosoglutathione and a ‘protein‐bound nitrite’ model system with N‐methylaniline at pH 5.5 and 37°C have been compared. The results show that the rate of nitrosamine formation from sodium nitrite and S‐nitrosocysteine is greater than that from the model system although the latter depends upon the local concentration of nitrosothiol groups on the matrix. Transnitrosation by S‐nitrosoglutathione is considerably slower than the other reactions. The implications of the results with respect to nitrosamine formation in cured meat are discussed.