Identification of Characterizing Aroma Components of Roasted Chicory "Coffee" Brews

The roasted and ground root of the chicory plant (Cichorium intybus), often referred to as chicory coffee, has served as a coffee surrogate for well over 2 centuries and is still in common use today. Volatile components of roasted chicory brews were identified by direct solvent extraction and solvent-assisted flavor evaporation (SAFE) combined with gas chromatography-olfactometry (GC-O), aroma extract dilution analysis (AEDA), and gas chromatography-mass spectrometry (GC-MS). A total of 46 compounds were quantitated by stable isotope dilution analysis (SIDA) and internal standard methods, and odor-activity values (OAVs) were calculated. On the basis of the combined results of AEDA and OAVs, rotundone was considered to be the most potent odorant in roasted chicory. On the basis of their high OAVs, additional predominant odorants included 3-hydroxy-4,5-dimethyl-2(5H)-furanone (sotolon), 2-methylpropanal, 3-methylbutanal, 2,3-dihydro-5-hydroxy-6-methyl-4H-pyran-4-one (dihydromaltol), 1-octen-3-one, 2-ethyl-3,5-dimethylpyrazine, 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF), and 3-hydroxy-2-methyl-4-pyrone (maltol). Rotundone, with its distinctive aromatic woody, peppery, and "chicory-like" note was also detected in five different commercial ground roasted chicory products. The compound is believed to an important, distinguishing, and characterizing odorant in roasted chicory aroma. Collectively, a group of caramel- and sweet-smelling odorants, including dihydromaltol, cyclotene, maltol, HDMF, and sotolon, are also thought to be important aroma contributors to roasted chicory aroma.