Abstract: A new method for the quantitation of ethyl carbamate (EC) in Maotai-flavor Baijiu was developed using ultra-high performance liquid chromatography-high resolution mass spectrometry with primary daughter ions. Based on the fact that it has the special property of in-source fragmentation, EC was detected under the full scan model. The primary parent ion with m/z 90.05 was used as qualitative ion and its daughter ion with m/z 62.02 as both qualitative and quantitative ions considering that a great noise and low response values were achieved respectively when using the primary parent ion and the secondary daughter ion as quantitative ions. The calibration curve showed good linearity in the range of 12.2–244 μg/L with a correlation coefficient greater than 0.999. The limit of detection (LOD) was 0.95 μg/L. The recoveries of EC from spiked samples were 83.46%–106.79%, with relative standard deviations (RSD) of 0.67%–3.54%. Overall, the method was suitable for the quantitation of EC in Maotai-flavor Baijiu with the advantages of rapidity, low detection limit and high accuracy.

Key words: ethyl carbamate; in-source fragmentation; Q Exactive Focus mass spectrometry; primary daughter ion quantitation; Maotai-flavor Baijiu