快速测定含水溶液中乙醇的氧同位素比值
近年来,乙醇的氧同位素比值(δ^18O)在果汁和饮料酒真实性鉴别中起着重要作用,利用该指标可检测产品中的外源水、追溯产品的产地。本工作采用多孔聚合物气相色谱柱实现了水与乙醇的在线快速分离,建立了溶剂稀释后直接用气相色谱-裂解-稳定同位素比值质谱(GC-TC-IRMS)测定溶液中乙醇δ^18O值的方法。实验结果表明,该方法可排除水对乙醇δ^18O分析的干扰,乙醇浓度在1%~100%时测定稳定性良好,在不同水溶液中乙醇δ^18O的测定值保持一致;乙醇δ^18O值重复性和再现性的标准偏差均优于0.5‰,并通过欧盟实验室间能力验证(FIT-PTS)证明了方法的准确性。该方法具有样品用量少(仅需70~2...
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Published in | 质谱学报 Vol. 37; no. 5; pp. 471 - 480 |
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Main Author | |
Format | Journal Article |
Language | Chinese |
Published |
全国食品发酵标准中心,北京100015
2016
中国食品发酵工业研究院,北京100015 |
Subjects | |
Online Access | Get full text |
ISSN | 1004-2997 |
DOI | 10.7538/zpxb.youxian.2016.0033 |
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Summary: | 近年来,乙醇的氧同位素比值(δ^18O)在果汁和饮料酒真实性鉴别中起着重要作用,利用该指标可检测产品中的外源水、追溯产品的产地。本工作采用多孔聚合物气相色谱柱实现了水与乙醇的在线快速分离,建立了溶剂稀释后直接用气相色谱-裂解-稳定同位素比值质谱(GC-TC-IRMS)测定溶液中乙醇δ^18O值的方法。实验结果表明,该方法可排除水对乙醇δ^18O分析的干扰,乙醇浓度在1%~100%时测定稳定性良好,在不同水溶液中乙醇δ^18O的测定值保持一致;乙醇δ^18O值重复性和再现性的标准偏差均优于0.5‰,并通过欧盟实验室间能力验证(FIT-PTS)证明了方法的准确性。该方法具有样品用量少(仅需70~200μL)、分析速度快(约18min)、操作简单方便等特点,可为乙醇δ^18O在果汁和饮料酒真实性领域的研究与应用提供方法参考。 |
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Bibliography: | ZHONG Qi-ding1,2 ,WANG Dao -bing 1,2,LI Guo -hui1,2 (1. China National Research Institute of Food and Fermentation Industries ?, Beijing 100015, Chinas 2. National Standardization Center of Food&Fermentation Industry , Beijing 100015, China) 11-2979/TH ethanol; stable oxygen isotoperatio; aqueous samples; e xtraction During thelast years , it has been demons t rated that δ^18O isotope an aly sis of ethanol in juices and alcoholic beverages provides powerful information to assess their adulteration by addition of water, or to authenticate their geographical origin. Howev-er, it is difficult to accurately and conveniently quantify it due to the measurement prin-ciple and its water miscibility. To eliminate the impact of water on ethanol δ^18O analy-sis ,a porous-polymer-bonded GC column was used to achieve a baseline separation of ethanol and water, then the water was vented by backflush function and the ethanol was converted and analyzed. This is the first manuscript presenting a systematic evaluation and charact |
ISSN: | 1004-2997 |
DOI: | 10.7538/zpxb.youxian.2016.0033 |