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Third-party-funded project

Title:
Multielement analysis of flavour compounds by on-line gas chromatography isotope ratio mass spectrometry

Project management at the University of Würzburg:

Participating scientists:

Abstract:
Besides the enantiodifferentiation the determination of the isotope ratios of the bioelements C, H , and O is the most reliable method to obtain information about the authenticity of flavour compounds. Working with stable isotopes the MS techniques are the most variable methods to measure isotope ratios. Whereas on-line techniques coupled with gas chromatography (HRGC) to determine 13C/12C ratios are availble since years, on-line HRGC coupling for isotope ratio analysis of oxygen and hydrogen isotope ratios was introduced just recently. Several years before, only laborious and milligram amounts of pure substances requiring techniques were known.

Providing elemental analyzers (EA) and an HRGC-IRMS systems with coupled reactors to produce the required measuring gases, i.e. combustion (C) and pyrolysis (P) to generate CO2, H2 and CO for on-line analyses of 13C/12C, 2H/1H and 18O/16O ratios, respectively, fundamental studies had to be peformed to evaluate the possibilities and limits of these novel techniques. After having coupled the HRGC-IRMS system with the EA (C/P), problems were solved at the examplary selected flavour compounds benzaldehyde, C6-aldehydes and -alcohols, as well as estragol and methyleugenol considering (i) the standardisation in the pyrolysis mode for 18O/16O and 2H/1H determinations, and (ii) the multielement analysis after various sample preparation techniques of these industrially attractive flavour compounds. The method creates the fundament for effective control of raw materials in industrial processes as well as -in consumer protection- for the realization of steps again food adulteration

Key words:
    Stable isotopes
    Isotope ratio mass spectrometry
    Multielement analysis
    Authenticity
    Flavour
    Natural flavours
    Origin analysis
    Green notes
    Deuterium
    HRGC-IRMS

Projekt period: from 01.1999 to 12.2001

Funding institution:
Wirtschaftsunternehmen ,Granting date: 01.11.1999

Publications:

Links:
Research area