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Characterization of vanillin carbon isotope delta reference materials
Michelle M G Chartrand1, Juris Meija2, Jean-Francois Hélie3
1National Research Council Canada, 1200 Montreal Rd., Ottawa, ON, K1A 0R6, Canada. Michelle.Chartrand@nrc-cnrc.gc.ca.
Analytical and Bioanalytical Chemistry
|October 5, 2022
Summary
Stable carbon isotope ratios help determine vanillin origin. New synthetic vanillin reference materials, VANA-1 and VANB-1, are introduced for accurate carbon isotope delta measurements, aiding in vanillin provenance studies.
Area of Science:
- Analytical Chemistry
- Isotope Geochemistry
- Food Science
Background:
- Stable carbon isotope ratio measurements are crucial for tracing the origin and authenticity of food compounds.
- Vanillin, a widely used flavoring agent, can be synthesized or derived from natural sources, necessitating reliable analytical methods for provenance determination.
- Variability in carbon isotope delta values of commercial vanillin samples requires established reference materials for accurate analysis.
Purpose of the Study:
- To establish reference materials for the calibration of carbon isotope delta measurements of vanillin.
- To provide a frame of reference for the natural variability of carbon isotope delta values in vanillin samples.
- To develop and characterize synthetic vanillin reference materials (VANA-1 and VANB-1) for analytical applications.
Main Methods:
- Analysis of commercial vanillin and vanilla products to determine the range of carbon isotope delta values.
- Preparation and characterization of two synthetic vanillin reference materials, VANA-1 and VANB-1.
- Multi-laboratory characterization of VANA-1 and VANB-1 for certified carbon isotope delta values, traceability, homogeneity, and stability.
Main Results:
- Commercial vanillin samples exhibited carbon isotope delta values ranging from -20.6‰ to -36.7‰ relative to Vienna Peedee Belemnite (VPDB).
- Certified carbon isotope delta values for the synthetic reference materials were determined as -31.30 ± 0.06‰ for VANA-1 and -25.85 ± 0.05‰ for VANB-1 (95% confidence level).
- The uncertainties incorporate measurement variability, reference material coherence, batch homogeneity, and stability, ensuring reliable calibration.
Conclusions:
- VANA-1 and VANB-1 serve as valuable, traceable reference materials for carbon isotope delta measurements of vanillin.
- These reference materials will enhance the accuracy and reliability of vanillin provenance studies and authenticity testing.
- The development supports the precise quantification of carbon isotope ratios in organic materials, crucial for various scientific disciplines.
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