Simultaneous determination of ethyl carbamate, chloropropanols and acrylamide in fermented products, flavoring and related foods by gas chromatography-triple quadrupole mass spectrometry

A simultaneous determination method was established by gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) for ethyl carbamate, acrylamide and chloropropanols (1,3-dichloropropane-2-ol (1,3-DCP), 2,3-dichloropropane-1-ol (2,3-DCP), 3-monochloropropane-1,2-diol (3-MCPD) and 2-monochloropropane-1,3-diol (2-MCPD)) in fermented products, flavoring and related foods. Ethyl carbamate-d5, 1,3-DCP-d5, 3-MCPD-d5 and acrylamide-d3 were used as isotope internal standards for ethyl carbamate, DCPs, MCPDs and acrylamide, respectively. The sample was extracted and cleaned in one single step by a combined clean-up column packed with Extrelut™ NT and primary secondary amine (PSA). The concentrated extract was directly injected without derivatization, separated by an Innowax (cross-bonded polyethylene glycol) capillary column and measured by GC-MS/MS. The calculated limits of detection (LODs) in the sample matrix were 1.8, 1.0, 2.1, 5.3, 5.1 and 5.0 μg kg−1 for ethyl carbamate, 1,3-DCP, 2,3-DCP, acrylamide, 3-MCPD and 2-MCPD, respectively. The average recoveries in different matrices at three spiked concentration levels (20, 100 and 400 μg kg−1) were 88.6-112, 92.6-103, 92.1-106, 86.2-107, 90.4-109 and 91.0-105% with relative standard deviations (RSDs) (Average RSDs in bracket) of 4.4-10.2 (6.4%), 3.7-7.3 (5.4%), 3.9-7.7 (5.2%), 4.4-9.3 (6.4%), 4.1-10.7 (6.3%) and 3.7-7.9% (5.6%), respectively. Two to six contaminants were simultaneously found in some of the soy sauce samples. Ethyl carbamate, acrylamide, 3-MCPD and 2-MCPD were found in the instant noodle flavoring. Trace levels (<12 μg kg−1) of ethyl carbamate, acrylamide or 3-MCPD were detected in tomato sauce and salad dressing. Both ethyl carbamate and acrylamide were found in some of the curry products and Chinese yellow rice wine. Only ethyl carbamate was found in beer and grape wine.