The effect of nitrite addition on N-nitrosamine formation in different processed meat products from the Danish Market

For decades, nitrite curing has been a widely used method to preserve meat products. Addition of nitrite inhibits the growth of some pathogenic microorganisms as well as lipid oxidation. Furthermore, it contributes to the development of a unique colour, and formation of flavours and aromas. However, during the production and storage of nitrite-cured meat, N-nitrosamines (NAs) can be formed. So far, 20 different NAs have been identified in processed meat products, and among them, many are considered potent carcinogens. NAs include both volatile and non-volatile compounds, and are created by the reaction of nitrite and secondary amines naturally present in meat. Numerous factors, such as the ingoing amount of nitrite or meat quality, can potentially affect the formation of NAs. Therefore, usage of nitrite is regulated in the EU legislation (Directive2006/52/EC) and generally limited to 150 mg per kg of meat. Due to safety concerns, the Danish authorities maintain national provision generally allowing a maximum of 60 mg of nitrite per kg of meat. The present study focuses on the estimation of NA levels in processed meat products commonly available on the Danish market. For this purpose, a new efficient, precise and robust analytical method was developed and validated, for the simultaneous determination of both the volatile (NDMA, NMEA, NPYR, NDEA, NPIP, NDPA, NDBA) and non-volatile (NPRO, NTCA, NMTCA) NAs in processed meat products. The method is based on the established methods described in Herrmann et al.¹ and Lehotay et al.². Separation and quantification were carried out by liquid chromatographycoupled with tandem mass spectrometry (LC-MS/MS) using both atmospheric pressure chemicalionization (APCI) and electrospray ionization (ESI). To demonstrate precision, accuracy, specificity,and limit of detection, the method was validated in accordance with ISO 5725-2, using spiked samples of three different processed meat products varying in fat content. Validation results were generally satisfactory with recoveries of 60-110% and RSDs <20. Employing the described method, numerous processed meat samples have been analysed to monitor NA levels and assess the potential hazard to the Danish population, associated with processed meat consumption.