Identification of off-flavor compounds in beer

Off-flavors in beer and brewing materials were identified. When the concent ration of the flavor component was high, abnormal peaks were detected on th e gas chromatogram. When an off-flavor was detected by tasting, the putativ e component was analyzed by gas chromatography mass spectrometry (GC-MS). W hen the concentration of the flavor component was low and the flavor compon ent could not be determined directly by tasting, the peak of the flavor com ponent was located by GC olfactometry and then identified by GC-MS. Beer co ntains many volatile components, so it is difficult to locate the peaks of minor flavor components on gas chromatograms by GC olfactometry. The peaks of minor flavor components in beer were located by multidimensional GC olfa ctometry and identified by multidimensional GC-MS. Using these techniques, solvent-like flavor adhering to can bodies, sea urchin egg-like flavor adhe ring to diatomaceous earth, and musty and disinfectant-like flavors in beer were identified.