Variation in Headspace Volatiles of Saffron Determined by GC×GC-ToF-MS

Saffron, obtained from the stigmas of Crocus sativus L (Iridaceae), is the most expensive spice traded worldwide. In addition to its culinary uses, various medicinal properties have been confirmed for saffron, which has recently captured the interest of the phytotherapy industry. The quality of saffron is determined by the presence of 3 compounds, namely, crocin, picrocrocin, and safranal, with the latter being responsible for the distinct aroma characteristic of saffron. To determine the volatiles and assess possible geographical variation, headspace analysis using 1-dimensional and 2-dimensional gas chromatography (GC) on 26 samples collected from 9 countries was undertaken. The major constituents identified include safranal, 4-ketoisophorone, acetic acid, 2(5H)-furanone, and 1,4-cyclohexanedione-2,2,6-trimethyl. Quantitative rather than a qualitative variation was noted in the samples from different origins. The levels of safranal ranged from 22.1% to 62.4%. This study represents the first report on the headspace volatiles of saffron using GC×GC-time-of-flight-mass spectrometry and clearly demonstrates the superior chromatographic potential of 2-dimensional GC compared with conventional 1-dimensional GC.