Identification of Off-Flavor Compounds in Beer

Abstract

Off-flavors in beer and brewing materials were identified. When the concentration of the flavor component was high, abnormal peaks were detected on the gas chromatogram. When an off-flavor was detected by tasting, the putative component was analyzed by gas chromatography mass spectrometry (GC-MS). When the concentration of the flavor component was low and the flavor component could not be determined directly by tasting, the peak of the flavor component was located by GC olfactometry and then identified by GC-MS. Beer contains 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 olfactometry and identified by multidimensional GC-MS. Using these techniques, solvent-like flavor adhering to can bodies, sea urchin egg-like flavor adhering to diatomaceous earth, and musty and disinfectant-like flavors in beer were identified.