Influence of cooking and storage conditions on the formation of N-nitrosamines in processed meats and pickled fish

Nitrate in food may undergo transformation to nitrite via bacterial action, subsequently reacts with amine-based substances to form carcinogenic N-nitrosamines. The current study investigated the effects of different cooking methods and storage time on alterations in the levels of nitrate, nitrite, and N-nitrosamine in processed meats commonly consumed by the Taiwanese population. Processed meats were stored at 4 °C for 0, 3, and 7 days, followed by common Taiwanese cooking methods. The highest average concentration of total N-nitrosamines was found in stir-frying cured meat. Nitrate and nitrite levels decreased with storage time, whereas N-nitrosamine levels increased over the 7-day storage period. Results also suggested that prolonged storage time is a crucial factor affecting N-nitrosamine in processed meats, potentially more important than the cooking method. The findings of this study can guide cooking recommendations, and it may be advisable to avoid air-frying Taiwanese sausages due to the high concentrations of N-nitrosamines observed. • Nitrate and nitrite levels decreased with storage time, whereas N-nitrosamine levels increased over storage period. • The highest average concentration of total N-nitrosamines was found in stir-frying cured meat. • Prolonged storage time is a crucial factor affecting N-nitrosamine content in processed meats. • Meat types significantly impacted nitrate, nitrite, and N-nitrosamines levels in 135 processed meat samples.