Composition of crocins and picrocrocin from Spanish saffron (Crocus sativus L.)

A method for simultaneous identification and quantification of crocins and picrocrocin by HPLC-DAD in aqueous extracts of saffron spice was used. The coefficients of variation obtained were lower than 10% for a majority of the crocins and picrocrocin. These substances are not found as standard compounds, for this reason it was necessary to obtain the response factor for each compound by collecting the fractions of each chromatographic peak and by using molar absorpitivity. This method can be used nor only for crocins and picrocrocin determination but also for adulteration detection of saffron with water-soluble colorants. The method was applied to 260 samples of Spanish saffron, which came from the regions where saffron is an important crop, i.e., Castilla-La Mancha and Aragon. Spain is in the top group of saffron producers and Castilla-La Mancha is the largest saffron producing region in Spain. Four crocins and picrocrocin were ranked and the values used for differentiation according to origin. Only discriminant analysis could explain 100% of the variance by samples and location. The major discriminant variable was trans-crocin 4.