Rapid determination of nitrosamines in sausage and salami using microwave-assisted extraction and dispersive liquid-liquid microextraction followed by gas chromatography-mass spectrometry

In this study, an efficient, sensitive, and rapid method based on microwave-assisted extraction coupled with dispersive liquid-liquid microextraction (DLLME) followed by gas chromatography-mass spectrometry for determination and quantification of seven nitrosamines (NAs) in heated meat products (sausage and salami) was developed. At extraction stage, nitrosamines were extracted from sausage and salami samples with 10 mL of a hydrolyzing solvent using microwave at 500 MHz for 1.5 min. Effective parameters on DLLME, such as volumes of extraction and disperser solvents, pH, and salt addition, were optimized using response surface methodology based on central composite design. This technique provided acceptable repeatability in the range of 3.5-5.4 % for spiked samples. The recoveries of NAs were in the range 83.9-109.4 %. Limits of detection and limits of quantification for NAs in the real samples were within the ranges of 0.11-0.48 and 0.41-1.45 ng g(-1), respectively. Good linear ranges were obtained for seven NAs in the range of 0.1-200 ng mL(-1), with the coefficient (R (2)) higher than 0.99. The merit figures, compared with other methods, showed that new proposed method is an accurate, precise, and reliable sample pretreatment method that substantially reduces sample matrix interference and gives very good enrichment factors (126-152).