ポスター発表
- 第1日 5月15日(火) ポスター会場
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1P-17 PDF
ポストカラム‐LC/IRMSを用いたはちみつの化学成分の炭素安定同位体比分析
In 2004, liquid chromatography coupled with isotope ratio mass spectrometry (LC/IRMS) has been developed, which allows the measurement of stable carbon isotope (δ13C) composition of highly polar and non-volatile analyses. However, LC/IRMS has several disadvantages, including the high cost of the CO2 membrane, the low total flow rate, etc. Here, we developed an improved system for determining carbon isotope ratios by LC/IRMS. Particularly, the column flow rate can be changed arbitrarily by the post column method. We applied the improved method to 26 commercial honey samples and one syrup sample to identify the authenticity of honey.
By LC/IRMS analysis, the δ13C values for glucose, fructose, disaccharides, trisaccharides, and organic acids ranged from –27.0 to –24.2‰, –26.8 to –24.0‰, –28.8 to –24.0‰, –27.8 to –22.8‰, and –30.6 to –27.4‰, respectively. In this study, we classified Δδ13C (fructose – glucose) values of >±1.0‰ or Δδ13C values of difference of each compound of > ± 3.0‰ as indicating adulteration. Using these authenticity criteria, we judged five samples to be adulterated. These results indicate that LC/IRMS is a powerful method for detecting adulterated honey.