N‐nitrosamines, widespread contaminants, can be formed from precursors in food including nitrites and amines. The effects of six cooking methods (roasting, stir frying/griddling, frying, blanching, boiling, and others) were investigated in terms of the concentrations of seven N‐nitrosamines including N‐nitrosodimethylamine, N‐nitrosomethylethylamine, N‐nitrosodiethylamine, N‐nitrosodibutylamine, N‐nitrosopiperidine, N‐nitrosopyrrolidine, and N‐nitrosomorpholine in Total Diet Study samples. In conclusion, N‐nitrosodimethylamine, N‐nitrosodiethylamine, and N‐nitrosopyrrolidine increased during boiling (5.26, 1.42, and 1.31 μg/kg each, p < .05), N‐nitrosodiethylamine contents increased in blanching, roasting induced N‐nitrosodimethylamine increases, and microwave heating increased N‐nitrosodiethylamine concentration (0.25, 1.73, and 0.15 μg/kg each, p < .05). Overall, N‐nitrosodimethylamine was the most frequently detected N‐nitrosamine (51.0%), boiling produced the most N‐nitrosamine, and N‐nitrosamines were found most frequently in fish samples. Based on the results, we recommend avoiding boiling or discarding boiled water to reduce risk from the food‐borne N‐nitrosamines. This research could improve our understanding of N‐nitrosamine changes by cooking in wide ranges of food products.
Practical applications
N‐nitrosamines can increase during boiling, blanching, roasting, and microwave heating. Boiling fish and cooking with seasoning might cause significant increases in N‐nitrosamines. Because N‐nitrosamines are not good for humans, cooking methods and food ingredients should be considered carefully.
