On the quality control of traded saffron by means of transmission Fourier-transform mid-infrared (FT-MIR) spectroscopy and chemometrics

The present study aimed to extend application of the FT-MIR technique to the quality control of traded saffron that suffers various types of fraud or mislabelling. Spectroscopic data were obtained for samples stored for different periods in the dark. Samples with the highest quality according to ISO 3632 specifications produced a typical spectrum profile (reference set). Principal Component Analysis (PCA) of spectroscopic data for this set along with HPLC-DAD analysis of major apocarotenoids assisted identification of FT-IR bands that carry information about desirable sensory properties that weaken during storage. The band at 1028 cm−1, associated with the presence of glucose moieties, along with intensities in the region 1175-1157 cm−1, linked with breakage of glycosidic bonds, were the most useful for diagnostic monitoring of storage effects on the evaluation and test set samples. FT-IR was found to be a promising, sensitive and rapid tool in the fight against saffron fraud.