Comparison of suitability of SPME, SAFE and SDE methods for isolation of flavor compounds from extruded potato snacks

The aim of this study was to compare the usefulness of three extraction methods: SPME (solid-phase microextraction), SAFE (solvent-assisted flavor evaporation) and SDE (simultaneous distillation and extraction) for isolation of flavor compounds from extruded potato snacks for their subsequent analysis using GCO/AEDA and GC/MS techniques. Results showed that the most suitable extraction method for GC–olfactometry (GC–O) was SAFE, by which it was possible to isolate all 25 potent odorants which contribute to overall flavor of potato snacks due to the application of high vacuum and low extraction temperature. Extraction using SDE method resulted in formation of 5 additional compounds: 2-furfurylthiol, 2,5-dimethyl-3-furanthiol, octanal, (E)-2-octenal and nonanal recognized as artifacts. On the other hand, sniffing extracts from SPME fiber did not reveal 7 important compounds such as: 1-octen-3-ol, 2-ethyl-3,5-dimethylpyrazine, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 3-hydroxy-4,5-dimethyl-2(5H)-furanone, 5-methyl-2,3-diethylpyrazine, β-damascenone or an unknown with a flavor of fresh pepper. However, this extraction method was shown to be very precise (RSD 3–9%), sensitive (lowest LOD for 6 compounds) and suitable for analysis of low boiling compounds, co-eluting with solvent in SDE or SAFE extracts. Preferably both SPME and SAFE methods should be used for a full characterization of odor-active compounds in potato snacks.