This paper assesses the fluctuation of relative response factors (RRFs) for the quality control of alcoholic products by GC-MS, using two internal standard (IS) methods, namely, a commonly used IS method using 1-pentanol, and "Ethanol as IS" method. To evaluate the variation of calibration factors values the Taguchi designed experiment was used.
Matrix composition, volatile compounds concentrations, injected volume of the sample, GC injector temperature and split ratio were the five selected control factors. Within the experiment each of these control factors took one from three possible values to create 27 various measuring conditions.
The results of the experiment revealed, that relative standard deviations of RRFs within all 27 measuring conditions were 7.3 +/- 4.1% for the 1-pentanol method and 36.3 +/- 3.5% for the ethanol method. The possible reasons of calibration factors variation were also discussed.