The 6890 HP model (USA) consisted of flame
ionization detector (FID) with temperature set at 300 C and capillary
column (HP-FFAP 30 m 0.25 mm 0.25 lm). The oven
time–temperature profile was as follows: 120 C (1 min), 25 C
per min to 180 C (1 min), 5 C per min to 220 C (10 min), 5 C
per min to 230 C (30 min). The carrier gas was helium with total
flow through the column 64.0 mL/min. The samples were analysed