Simultaneous determination of total fatty acid esters of chloropropanols in edible oils by gas chromatography-mass spectrometry with solid-supported liquid-liquid extraction.
This study aimed to establish a novel robust method for the simultaneous determination of total fatty acid esters of 4 chloropropanols including fatty acid esters of 3-monochloropropane-1,2-diol (3-MCPD esters), 2-monochloropropane-1,3-diol (2-MCPD esters), 1,3-dichloropropan-2-ol (1,3-DCP esters) and 2,3-dichloropropan-1-ol (2,3-DCP esters) in edible oils. In this method, sodium methylate in methanol was used as the reagent for the ester cleavage reaction of chloropropanols esters. The reaction products were extracted by a sodium sulfate solution, and then purified by solid-supported liquid-liquid extraction (SLE) using diatomaceous earth (Hydromatrix™) as the sorbent. Finally, the extracts were derivatized with heptafluorobutyrylim idazole (HFBI) and analyzed by gas chromatography-mass spectrometry (GC-MS). Quantification was achieved using deuterated chloropropanols as their respective internal standards, including 3-MCPD-d5, 2-MCPD-d5, 1,3-DCP-d5 and 2,3-DCP-d5. A good linear relationship between peak area and concentrations was obtained within the range of 0.025-2.000mgL(-1) with a correlation coefficients not less than 0.999 for all the chloropropanols esters. The limits of detection (LODs) of esters of 3-MCPD, 2-MCPD, 1,3-DCP and 2,3-DCP (calculated as corresponding chloropropanols) were 30, 30, 100 and 30μgkg(-1), respectively. The average recoveries of the 3-MCPD esters and the 4 chloropropanols spiked at 0.1, 0.5 and 2mgkg(-1) into blank oil matrix were typically in a range from 70.7% to 113.3%. The robust method validation data including calibration, LOD/LOQ, accuracy and repeatability and proficiency test results (Z-score: -0.5) of the official Food Analysis Performance Assessment Scheme (FAPAS) indicated that the present quantitative method could be successfully applied to the determination of total chloropropanols esters in various edible oils.
Key Laboratory of Food Safety Risk Assessment, Ministry of Health; China National Center of Food Safety Risk Assessment, Beijing 100021, China.
Qing
Q
Liu
Feng
F
Han
Ke
K
Xie
Hong
H
Miao
Yongning
Y
Wu
D004042:Dietary Fats, Unsaturated / Q000032:analysis*; D004952:Esters / Q000032:analysis*; D005227:Fatty Acids / Q000032:analysis* / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D057230:Limit of Detection; D059625:Liquid-Liquid Extraction / Q000379:methods*; D020005:Propanols / Q000737:chemistry*; D012015:Reference Standards
D004042:Dietary Fats, Unsaturated; D004952:Esters; D005227:Fatty Acids; D020005:Propanols
Chloropropanols esters; Edible oils; Gas chromatography–mass spectrometry (GC–MS); Heptafluorobutyrylim idazole (HFBI); Solid-supported liquid–liquid extraction (SLE)