Identification of a Woody-hay Odor-causing Compound in a Drinking Water Supply

β-Cyclocitral and geosmin have been identified as the chemicals responsible for causing hay/woody and earthy odors in Lake Winnebago, respectively. Initial identifications of off-flavors were made by the GC-MS with an MS spectral library and sensory-GC analysis and the identifications were confirmed by GC retention time and MS spectral matches to the known standard compounds. A Weber-Fechner plot has been developed for β-cyclocitral and its three odor descriptors, fresh grass, hay/woody, and tobacco-like, which were observed at different concentration ranges.