为研究空气氛围中叶黄素的热解行为，设计了捕集热重逸出组分的自动单液滴微萃取（SDME）装置，并与气相色谱/质谱（GC/MS）结合。根据TG/DTA（差热分析）结果，在155~400℃范围内，划分16个温度段连续取样。通过比较每个温度段的质量损失和裂解产物的总峰面积，分析了以乙醇为萃取剂SDME的萃取效果。通过监测43种主要逸出组分相对含量的动态变化，对叶黄素在空气氛围中发生热裂解的可能机理进行了推导。结果表明：①优化后热分析条件为升温速率5℃/min,载气流量400 mL/min。②SDME对于裂解产物中挥发性组分具有优异的萃取效果。③GC/MS鉴别出的主要裂解成分包括酮类、醛类、醇类、烯烃和芳香烃类化合物，其中最重要的裂解产物有β-大马酮、巨豆三烯酮和氧化异佛尔酮。%To investigate the pyrolysis behavior of lutein in air, an automatic single drop microextraction (SDME) device for trapping the released fractions was designed and coupled with gas chromatography-mass spectrometry. According to the results of differential thermal-thermo gravimetric analysis (TG-DTA), the pyrolysis process was divided into 16 temperature sections in the range of 155-400℃, and the released fractions at each section were sampled successively. The extract effect of SDME with ethanol as a solvent was analyzed by comparing the mass loss in each temperature section with the total peak area of pyrolysis products. The probable mechanism of lutein pyrolysis in air was inferred on the basis of dynamically monitoring the changes of relative contents of 43 main pyrolysis components. The results indicated that: 1) The optimized conditions for the thermoanalyzer were: temperature ascending rate 5℃/minute and carrier gas flow rate 400 mL/minute. 2) SDME performed excellently in the extraction of volatile components in pyrolysis products. 3) The main components identified by GC/MS included ketones, aldehydes, alcohols, alkenes and aromatic hydrocarbons, the most important pyrolysis products were β-damascenone, megastigmatrienone and 4-oxoisophorone.
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