Essentially, themethod
described by Chung (8) was followed for the identification and quantification of the volatile
compounds. The tentative identification of components was based on matching mass
spectra of unknown compounds with those in theWiley library of mass spectral database
(Hewlett-Packard Co.). The quantification of compounds in each sample was determined
by the standard curvemethod using the peak area of a specific fragment of a compound to
that of the IS, assuming a response factor of 1. The relative abundance of a tentatively
identified compoundwas calculated by the ratio of the relative area of a specific fragment of
the tentatively identified compound to the area of the internal standard.