Aromatic profile determination of different italian peach and nectarine cultivars by SPME-GC-MS

Italy has always produced great quality peaches and nectarines. These fruits could be with white or yellow flesh and have very distinct sensory profile. For this reason, the aim of this work was a screening and comparison of different peach and nectarine cultivars of the Emilia-Romagna area, in order to give a pattern recognition of these varieties from their volatile compounds. In particular, four white peaches varieties (“Buco Incavato”, “Bella di Cesena”, “Rosa del West”, “S. Anna Balducci”), two white nectarines varieties (“Magique” and “Romagna Red”) and one yellow nectarine variety (“Big Top”) were analysed. The aromatic compounds of the investigated cultivars were extracted by headspace solid phase microextraction (SPME), using a DVB/CAR/PDMS fiber and identified with a gas chromatograph (GC) coupled to a mass spectrometer (MS). Seventeen characteristic peach aroma compounds were identified and quantified using 1-octanol as internal standard. Both in white and yellow nectarines, 2-hexenal was the preponderant compounds, followed by hexanal, 1-hexanol, 3-hexenyl acetate, 2-hexenol and 2-hexenyl acetate. On the other hand, in white peaches the most abundant compound was hexanal, followed by 2-hexenal, 3- hexenyl acetate and 2-hexenyl acetate. Bella di Cesena was the only variety that showed a considerable linalool concentration. Besides, for “Buco Incavato” and “Big Top” the effect of ripening on the volatile components was also evaluated. The results show that maturation affects the volatile profile of peaches and nectarines: both in “Buco Incavato” and “Big Top” the aroma compound concentration decreased from first to the last harvest time. In particular, in the “Big Top” sample was observed an increase of the aroma profile at second harvest time, before the decrease at third and final harvest time.