Abstract
The aim of this work was to determine the most suitable sampling headspace technique for the study of strawberry (Fragaria ×ananassa Duch.) fruit aroma. The aromatic qualities of different headspace extracts of strawberry (‘Festival’) puree were evaluated using direct gas chromatography-olfactometry (D-GC-O), a technique that allows assessing global odor from solvent-free extracts without chromatographic separation. Two solid phase microextraction (SPME) extracts, with different types of fibers, polydimethylsiloxane/divinylbenzene (PDMS/DVB) and divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS), and two static headspace extracts, with different phase ratios (ratio of gas to sample phase volumes), were evaluated using D-GC-O. A similarity test with three panelists allowed comparison of the odor of these extracts to that of strawberry puree. The results indicated that SPME using a DVB/CAR/PDMS fiber generated the most representative odor, a “green” impression and a strong “fruity” note. A fruity note was also obtained with the 10-mL static headspace extracts, which exhibited a volatile concentration that was higher than that in the 20-mL headspace. When comparing the aroma profile of each extract, the DVB/CAR/PDMS extract showed the highest concentration of methyl butanoate and ethyl butanoate, two key compounds in strawberry aroma.
