Characterization of Key Aroma Compounds in Distiller’s Grains from Wheat as a Basis for Utilization in the Food Industry

The limited use of distiller's grains (DG) in the food industry depends occasionally on the characteristic odor of DG. For a better understanding of this typical odor, a sensory evaluation was performed first. The impressions seasoninglike, roasty/breadlike, and malty/caramellike were revealed as the most intensive odors. Furthermore, analysis of volatile flavor compounds was applied on dried DG from wheat. Isolation was performed by means of headspace solid-phase microextraction, solvent-assisted flavor evaporation (SAFE), and simultaneous distillation/extraction and identification with gas chromatography-olfactometry/mass spectrometry. As a result, 42 odor-active compounds could be identified in total. Among 24 of the 42 odor-active compounds obtained by SAFE, 3-hydroxy-4,5-dimethyl-2(5H)-furanone (seasoninglike) showed the highest flavor dilution (FD) factor, and 7 compounds (3-methylbutanioc acid, dimethyl trisulfide, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 2-ethyl-3,5-dimethylpyrazine, 2-phenylethanol, 2,6-nonadienal, and 5-ethyl-3-hydroxy-4-methyl-2(5H)-furanone) with a FD factor ≥ 32 were identified as key aroma compounds in DG from wheat.