多次顶空固相微萃取在大曲挥发性化合物定量中的应用

Application of Multiple Headspace Solid Phase Microextraction in Quantification of Volatile Compounds in Daqu

摘要:

应用顶空固相微萃取（headspace solid-phase microextraction，HS-SPME）结合气相色谱/质谱联用（gas chromatography-mass spectrometry，GC-MS），对古井贡酒中高温大曲进行分析，共定性出108种挥发性化合物。通过考察不同样品量下化合物的β值，在35和50mg样品量下，建立了应用多次顶空固相微萃取（Multiple headspace solid-phase microextraction，MHS-SPME）对醛酮类、酚类、含氮类、呋喃类、内酯类、萜烯类等46种化合物进行定量的方法。该方法回收率为76.83%-133.11%、最低检测限（limits of detection，LOD）低于103.818ppb、相对标准偏差（RSD%）小于21.34%，具有较好的灵敏度和重复性。实验结果表明MHS-SPME可适用于大曲中这46种化合物的定量分析，所测得的化合物含量在3645.79?442.43 ng/g（3-甲基-2(5H)-呋喃酮）~6.32?1.03 ng/g（3-乙基苯甲醛）之间。该方法为定量大曲中挥发性成分提供了新的思路，研究结果也为企业完善大曲质量评价体系提供了数据支持。

Abstract:

Headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) was used to analyze the medium high temperature Daqu in Gujing Gongjiu, and a total of 108 volatile compounds were identified. By examining the β values of the compounds under different sample amounts, multiple headspace solid-phase microextraction (MHS-SPME) was applied to quantify the aldehydes and ketones, phenols, nitrogen, furans, lactones, terpenes at the 35 and 50 mg samples, and a total of 46 compounds were quantified. The recoveries of the method ranged from 76.83%-133.11%, the limits of detection (LOD) were lower than 103.818 ppb, and the relative standard deviation (RSD%) were less than 21.34%, which showed the method had good sensitivity and repeatability. The experimental results showed that MHS-SPME could be applied to the quantitative analysis of these 46 compounds in Daqu. The contents of measured compounds ranged from 3645.79?442.43 ng/g (3-methyl-2(5H)-furanone) to 6.32?1.03 ng/g (3-ethylbenzaldehyde). This method provided a new idea for quantifying the volatile components in Daqu, and the results also provided data support for the enterprise to improve the Daqu quality evaluation system.