A headspace solid phase microextraction (HS-SPME), followed by gas chromatographic method was established for the detection of three pyrazine compounds (2,5-dimethyl pyrazine, 2,3,5-trimethyl pyrazine and 2,3, 5, 6-tetramethyl pyrazine) in cocoa wort. Equilibrium temperature and equilibrium time were optimized by using different SPME heads. According to the results of the optimization experiments, the following conclusion can be drawn: The cocoa wort sample was efficiently extracted under 40 ℃ for 40 min with 75 urn CAR/PDMS SPME head. The method had linear response within 1 - 500 mg/L, and the detection limits (S/N=3) were below 0. 023 礸/L. The relative standard deviations were from 3. 6%-6. 4% and the recoveries were from 95. A% to 102. 7%. This method is characterized by rapidly, high sensitivity, good linearity and repeatability for the analysis of cocoa wort samples.%建立了顶空-固相微萃取(HS-SPME)-气相色谱快速测定可可麦汁中3种吡嗪类物质(2,5-二甲基吡嗪、2,3,5-三甲基吡嗪和2,3,5,6-四甲基吡嗪)的方法.选择不同的固相微萃取头对萃取温度和时间进行优化,所得最佳萃取条件为:在60℃下,采用75 μm CAR/PDMS萃取头对麦汁样品萃取40 min.本方法的检出限(S/N=3)为0.023～ 0.056 μg/L,线性范围1～500 mg/L;相对标准偏差为3.6％～6.4％；回收率为95.4％～102.7％.本方法应用于样品检测,发现可可麦汁中吡嗪的浓度与原料中可可粉的添加量正相关,显示了很好灵敏性.
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