GCMS/SPME检测地沟油方法研究

Analysis and Identification of Waste Cooking Oil by GCMS/SPME

采用固相微萃取(SPME)与气相色谱-质谱技术(GCMS)对地沟油与商用植物油的识别检测进行了探索。结果表明:样品为0.050 g、无水硫酸钠为0.020 g、温度为120℃下萃取50 min,解析1 min时为最佳萃取条件。地沟油与商用植物油中均可以检测出庚醛(S1)和疑似间苯二胺(S2)的物质,A(S2/S1)值接近1为商用植物油,A值接近或大于10为地沟油。

Waste cooking oil is tentatively identified by GCMS(Gas chromatography-mass spectrometry)coupled with SPME(solid phase micro-extraction).The results show that Optimization of SPME for abstract and identification of waste cooking oil are as follows:0.05 g of sample to be taken,0.02 g of anhydrous sodium sulfate(Na2SO4)to be added,50 minutes under 120℃to be spent in extraction and 1 minute for desorption in GCMS.It is found that heptaldehyde and suspected m-phenylenediamine could be detected in waste cooking oil and vegetable oil from market in GCMS.A method of A value to identify waste cooking oil is put forward.A value,which is a ratio of S2/S1 where S2 is peak area of suspected m-phenylenediamine while S1 means peak area of heptaldehyde in TIC,can be used as an index to identify whether oils are from waste cooking or from market.A value of market oils is near to 1,while A value of waste cooking oils is near or more than 10.