同位素稀释-气相色谱-质谱法测定面包中3-氯-1,2-丙二醇脂肪酸酯
摘要
A method was established to detect 3-chloropropane-1,2-diol esters in bread products by gas chromatography-mass spectrometry (GC-MS). The bakery products were ultrasonically extracted with hexane, followed by transesterification with sodium methylate/methanol, and then passed through matrix solid-supported liquid-liquid extraction (SLE) for purification. After derivatization with heptafluoro butyrylimidazole (HFBI), 3-MCPD was determined using GC-MS. The target compounds were separated on a HP-5 capillary chromatographic column, and the tandem mass spectrograph was operated in the selected ion-monitoring mode (SIM). There was an excellent linear correlation (<italic>r</italic> = 0.9999) between the ratio of the 3-MCPD to the internal standard and the mass in the range of 0.025-1.600 mg/L of 3-MCPD esters (calculated as 3-MCPD). The limit of detection of 3-MCPD esters in bread products was 10 μg/kg. The recoveries of the 3-MCPD esters were in the range of 82.9%-113.7% at the spike levels of 40, 100, 160 and 240 μg/kg into blank bread products matrix, and the relative standard deviations (RSDs) were 2.1%-4.9%. The method is sensitive and accurate, which could be suitable for the determination of 3-MCPD esters in bread products.