Developing An Authentication Approach Using Spme-Gc-Irms Based On Compound-Specific Delta C-13 Analysis Of Six Typical Volatiles In Wine

An analytical method using gas chromatography isotope ratio mass spectrometry (GC-IRMS) combined with solid phase micro-extraction (SPME) was developed to measure the delta C-13 values of six typical volatiles commonly occurring in wine (isoamyl acetate, 2-octanone, limonene, 2-phenylethanol, ethyl octanoate and ethyl decanoate) for the first time. SPME selected with a divinylbenzene/carboxen/polydimethylsiloxane fiber was combined with the GC-IRMS for pretreatment optimization. The optimized SPME parameters of extraction time, extraction temperature and salt concentration were 40 min, 40 degrees C and 10%, respectively. The d13C values measured by SPME-GC-IRMS were in good agreement with those measured via elemental analyzer (EA)-IRMS and GC-IRMS. The differences range from 0.02 to 0.44% with EA-IRMS and from 0 to 0.28% with GC-IRMS, indicating the high accuracy of the method. This newly established method measured the precision within 0.30% and was successfully validated to discriminate imported real wine samples with identical label but amazing price differences from different importers.[GRAPHICS]