Detection of Vegetable Oil Adulteration Using Gas Chromatography Combustion/Isotope Ratio Mass Spectrometry

Abstract

A new method is described for detecting the adulteration of maize oil based on differences in <$13C values of oils arising through biosynthetic differences in the mode of carbon dioxide fixation in C4 and C3 plants. Fatty acid composition data are obtained on whole vegetable oils (following saponification and methylation) by GC using a capillary column with a polar stationary phase. 513C values for the individual fatty acids, determined by GCC/ IRMS, are then used together with the compositional data to construct theoretical mixing curves. The validity of these mixing curves was verified experimentally. The ability of the method to detect adulteration of maize oil with C3 oils at low concentrations was tested in a "blind" trial. The technique was readily able to detect adulteration

Analytical platforms to assess the authenticity of cocoa butter

“…GLC coupled to an isotope ratio mass spectrometer (IRMS) is a very dedicated technique to verify the purity of maize oil, since maize uses the C 4 photosynthetic pathway, while most other vegetable oils are produced by C 3 plants [55,56]. This technique has also been applied to CB with a view to discriminate them from CBEs [33].…”

Gas chromatography coupled to mass spectrometry for analyses of organic compounds and biomarkers as tracers for geological, environmental, and forensic research

“…Sterols are major components in unaltered sedimentary sections, and range from C 27 to C 29 , with cholesterol dominant or equal to sitosterol. Diagenetic alteration of sterols accelerated by thermal stress yields sterones and stanones with the same range from C 27 to C 29 . The products found are primarily from the regular aromatization of ring-C to ring-A, with some loss of the side chain and subsequent cracking to alkylphenanthrenes (Fig.…”

A review of current applications of mass spectrometry for biomarker/molecular tracer elucidations

“…The same situation is the case for food and wine chemistry (Webb, 1974;Flament, 2002;Bell et al, 2003). Those topics are not discussed further, except to mention that adulteration of products is one aspect in which the new method of CSIA by GC-isotope MS is of utility (Woodbury et al, 1995).…”