NEW APPROACH TO PROCESSING OF GAS-CHROMATOGRAPHIC MASS-SPECTROMETRIC DATA FOR DETECTION OF OFF-FLAVORS IN COMPLEX-MIXTURES

Chemical compounds responsible for off flavors in foodstuffs are often difficult to identify because of their low levels in complex matrixes . A simple method is described to detect and identify off flavor compo unds by gas chromatographic/mass spectrometric (GC/MS) analysis and da ta processing for sorting the GC/MS files in 14-ion series. The 14 hom ologous-ion series correspond to the sum of the intensities of the ion s, x + (CH2)(n) where x varies from 1 to 14 and n varies from 1 to inf inity, allowing to cover the whole acquired mass range. Processing of the ion series allows automatic screening of all acquired masses. We u se this method routinely in our laboratory to find compounds responsib le for a contamination. It is a powerful tool for off flavor identific ation by comparison between a reference and a contaminated sample. The method can be used with any type of data system and any chromatograph ic instrument coupled to a mass spectrometer.