Unveiling the case of adulteration ini a commerical saffron sample

In our previous study about the quality and authenticity of commercial saffron samples special attention was paid to the case of one sample that had been found suspicious for adulteration on the basis of UV-Vis and RP-HPLC-DAD data. To unveil this case of real fraud, systematic investigation was carried out taking into account analytical limitations due to sample amount available (< 1 g). In detail, the UV-Vis and FT-IR spectral databases for synthetic dyes, both created within the frame of SaffronOmics (AUTh-LFCT collection) were exploited using appropriate software facilities for mathematical treatment of the spectra e.g. electronic addition of the spectra of the unknown sample with those of various dyes at equal ratios. The composition of the commercial sample was also examined using multinuclear and multidimensional NMR spectroscopy. Lipophilic synthetic dyes and metabolic profiling of known plant adulterants were searched among the "in house" database created within the frame of SaffronOmics. Additional tests (solubility in less polar solvents, fluorescence etc) were also carried out to acquire complementary information. The so far results show that the counterfeit practice performed in this case involved chemical substances and additives which are mimicking the analytical response of pure saffron constituents under the ISO 3632-2 suggested conditions for the UV-Vis based determination of the main characteristics .