Ground samples (5 g) were heated to 30 °C and SPME fiber Polydimethylsyloxane-Divinyllbenzene
(PDMS-DVB) was introduced to the headspace of sample for 30 minutes. The fibre was reconditioned for 15
minutes into GC injection port. Flavour compounds (methyl pyrazine, dimethyl pyrazine, trimethyl pyrazine
and tetramethyl pyrazine) were separated using GC-FID equipped with Rtx-5(dimethylpolisiloxane crossbone)
capillary column, helium with 30 ml/min constant flow as carrier gas and injector SPL-1 operating in splitless
mode. GC temperature programmed from 60o
C (3 min) to 180o
C at 5o
C/min for 3 minute. Identification of the
component of the standard was carried out by comparing the retention time of standards and quantification
using the internal standard, 4-picoline