A He gas
stream carried the desorbed compounds to the GC through
a transfer line heated at 230 C. The GC was equipped with a 30 m,
0.53 mm, 2.65 mm Agilent HP-1 semicapillary column. The chromatographic
conditions were: He as the carrier gas, 210 C and
260 C injector and detector temperatures, 7 min at 45 C, heating
ramp to 220 C at 18 C/min, and 12 min more at 220 C. At the end
of the desorption process the sample was weighed with a 0.1 mg
precision balance (Voyager V11140 model, Ohaus, Switzerland).
Calibration was done by injecting known amounts of carvacrol or
citral in the desorption cell.