分散液液微萃取结合气相色谱-火焰光度检测器法测定芝麻香型白酒中3-甲硫基丙醇

Determination of 3-methylthiopropanol in Zhima-flavour Chinese spirits by dispersive liquid-liquid microextraction coupling with GC-FPD

研究了超声波辅助分散液液微萃取联合气相色谱测定芝麻香型白酒中3-甲硫基丙醇。筛选优化样品前处理条件,联合气相色谱-火焰光度检测器（gas chromatography-flame photometric detector,GC-FPD）测定其含量。结果表明：分散液液微萃取参数为萃取剂三氯甲烷65μL、分散剂甲醇100μL、样品体积1 m L、样品p H值为3、酒精度12%vol、Na Cl离子强度15%、低温分离时间1 h、离心时间3.5 min,3-甲硫基丙醇提取率为93.01%。在3-甲硫基丙醇质量浓度为50~2 000μg/L时,线性相关系数为0.999 4,检测限为1.5μg/L,定量限为5μg/L。在3-甲硫基丙醇质量浓度分别为50、100、200、400μg/L四个水平下,回收率为92.11%~101.90%。检测5个白酒样品中3-甲硫基丙醇含量,质量浓度分别为110.41~1 238.67μg/L,其中孔府家酒含量最高。

Ultrasound assisted dispersive liquid-liquid microextraction combined with gas chromatography was used to determine 3-methylthiopropanol in Zhima-flavour Chinese spirits. Pretreatment condition was selected to optimize the conditions of extracting 3-methylthiopropanol,and gas chromatography-flame photometric detector was used to determine the content. The results showed that the parameters of dispersive liquid-liquid microextraction were as follows： the extractant was 65 μL of chloroform,the dispersant was 100 μL of methanol,sample volume was 1 m L,p H value of sample was 3,alcohol concentration was 12% vol,ionic strength was 15% Na Cl,freezing time was 1 h,centrifugal time was 3. 5 min,and the extraction rate of 3-methylthiopropanol was 93. 01%. The linear correlation coefficient was 0. 999 4 in 3-methylthiopropanol concentration for 50 ~ 2 000 μg / L,the detection limit was 1. 5 μg / L,and the quantitation limit was 5 μg / L. The recovery rates were 92. 11% ~ 101. 90% in 4 concentration levels of 3-methylthiopropanol concentration（ 50,100,200,400 μg / L）. 3-Methylthiopropanol contents in 5 Chinese spirits were determined to be 110. 41 ~ 1 238. 67 μg / L,wherein the 3-methylthiopropanol content in Congfujia Chinese spirits was the highest.