| Deodorizer distillate, the by-product of vegetable oil refining, is the raw material for extraction and production of natural vitamin E and phytosterol. Based on the special viscous traits and complex components of deodorizer distillate, the detection methods of polycyclic aromatic hydrocarbons (PAHs) and the pretreatment conditions of samples were optimized. The liquid-liquid extraction-silica SPE column purification-isotope dilution-GC-MS method for quantitative detection of 16 PAHs in deodorizer distillate was established. The limits of detection and the limits of quantitation for PAHs were 0.10-028 μg/kg and 0.33-0.92 μg/kg, respectively. The recoveries ranged from 83.92% to 112.34%. Therefore, the method had high detection sensitivity, good stability, qualitative and quantitative accuracy, and could meet the detection of PAHs in deodorizer distillate. Through the detection and analysis of PAHs content in six deodorizer distillate samples, the average contents of BaP, PAH4 and PAH16 in deodorizer distillate were 11.89, 217.19, 2 268.85 μg/kg, respectively. LPAHs were the main PAHs pollutants accounting for 90.34%-95.61% of PAH16 in deodorizer distillate. The results suggested that the use of deodorizer distillate as raw material for the extraction of vitamin E and phytosterols should pay full attention to the safety risks of its PAHs. |
