Reduction, removal or replacement of sodium nitrite in a model of cured and cooked meat: a joint evaluation of consequences on microbiological issues in food safety, colon ecosystem and colorectal carcinogenesis

Scope Epidemiological and experimental evidence reported that processed meat consumption is associated with colorectal cancer (CRC) risk. Several studies suggest the involvement of nitrite or nitrate additives via N-nitroso-compound formation (NOCs).

Methods and results Compared to the reference level (120 mg/kg of ham), the effects of sodium nitrite reduction (90 mg/kg of ham), removal and replacement were analysed on ham characteristics and in a CRC rat model. Sodium nitrite removal and reduction induced a similar decrease in CRC preneoplastic lesions, but only reduction led to (i) an inhibitory effect on Listeria monocytogenes growth comparable to that obtained using the reference nitrite level of 120 mg/kg and (ii) an effective control of lipid peroxidation. Among the three alternatives tested, none led to a significant gain when compared to the 120 mg/kg ham reference level: vegetable stock, due to nitrate presence, was very similar to this reference nitrite level, yeast extract induced a strong luminal peroxidation and no decrease in preneoplastic lesions despite the absence of NOCs, and polyphenol rich extract induced the clearest downward trend on preneoplastic lesions but the concomitant presence of nitrosyl iron in feces. Except vegetable stock, other alternatives were less efficient than sodium nitrite (≥ 90 mg/kg) in reducing L. monocytogenes growth.

Conclusion Nitrite reduction (90mg/kg) effectively reduced CRC risk through limiting NOC formation and lipid peroxidation, while mitigating L. monocytogenes risks from cooked hams. Going further in reduction should be possible if accompanied by antioxidants to limit lipid peroxidation and appropriate use-by dates.