An integrated approach combining HPLC, GC/MS, NIRS, and chemometrics for the geographical discrimination and commercial categorization of saffron

In the present study, an integrated approach combining HPLC/DAD, GC/MS, near infrared (NIR) spectroscopy, and chemometrics was used to geographically discriminate saffron samples from Iran and China. Chinese and Iranian samples can be well-separated based on HPLC data analysed by a principal component analysis and an orthogonal partial least squares discriminant analysis. Picrocrocin and two types of crocins were found to be the discriminating variables, and the Chinese samples had higher contents of safranal and picrocrocin but lower cis-crocin 3Gg, kaempferol-3-O-sophoroside and isophorone. Furthermore, an NIR method was successfully established to rapidly distinguish the Chinese and Iranian samples. The relationship between an ISO standard and the contents of the chemical indices was also studied. The results indicated that the ISO standard should be revised, especially for analysing safranal.