Analysis of volatiles in Dezhou Braised Chicken by comprehensive two-dimensional gas chromatography/high resolution-time of flight mass spectrometry

A fast and mild extraction method and an accurate identification method to analyze the volatiles in nonvolatile food matrices were set up. The accelerated solvent extraction followed by solvent assisted flavor evaporation (ASE-SAFE) was used to extract the volatiles from Dezhou braised chicken. The extract was analyzed by a comprehensive two-dimensional gas chromatography/high resolution-time of flight mass spectrometry (GC x GC/HR-TOFMS) and a GC-qMS. Ninety one compounds were identified by GC x GC/HR-TOFMS with an aid of the NIST08 library and accurate mass determination, 44 compounds were identified by GC-qMS only with the NIST08 library. The main odor-active constitutes of the Dezhou braised chicken were carbonyl compounds (33.04%). 2-Enals and 2,4-dineals were considered to be the most important odor-active constitutes in chicken. In our study, 6 very polar and unstable 2-enals or 2,4-dineals compounds, including (E)-2-hexenal, (E)-2-nonenal, (Z)-2-decenal, (E)-2-undecenal, (E,E)-2,4-heptadienal and (E,E)-2,4-nonadienal, were only identified by GC x GC/HR-TOFMS. Three very polar and unstable furanones, including 5-acetyldihydro-2(3H)-furanone (0.04%), dihydro-3-hydroxy-4,4-dimethy1-2(3H)-furanone (0.32%) and 2,5-dimethy1-4-hydroxy-3(2H)-furanone (0.32%) were also only detected by the GC x GC/HR-TOFMS. Some trace sulfur-containing and nitrogen-containing compounds, including disulfide dipropyl (0.05%), 2-acetylthiazole (0.06%), 2-pyrrolidinone (0.15%) and benzothiazole (0.07%) that might play important roles in the flavor of chicken, were also only found by the GC x GC/HR-TOFMS. (C) 2014 Elsevier Ltd. All rights reserved.