After each experiment,
both tubing and valves were washed with hexane to collect the
extract that eventually had condensed there, and it was mixed
with the trapping solvent when used. Then, solvent was
distilled under vacuum to preconcentrate the extracted volatiles.
Finally, essential oils were stored in glass vials with Teflonsealed
caps and kept in the dark and cold (+4 °C) prior to
chemical analysis.