Characterization of typical potent odorants in raw and cooked Toona sinensis (A. Juss.) M. Roem. by instrumental-sensory analysis techniques

Toona sinensis (A. Juss.) M. Roem. (TS) possesses a unique and pleasant flavor and is consumed as a popular seasonal vegetable in certain parts of eastern and southeastern Asia. The potent odorants in raw and cooked TS were identified by combined sensory and instrumental analysis techniques, including sensory descriptive aroma profiling and two complimentary volatile isolation methods combined with gas chromatography-olfactometry (GC-O) techniques. Highly volatile odorants were determined by static headspace dilution analysis (SHDA)-GC-O, while those of intermediate- and semi-volatility were determined by solvent-assisted flavor evaporation-aroma extract dilution analysis (SAFE-AEDA). Among the numerous odorants identified by SHDA and SAFE-AEDA, ( E,E )- bis -(1-propenyl) disulfide was found to be predominant in both raw and cooked TS. In agreement with results of sensory descriptive analysis, hexanal, ( Z )-3-hexenal, ( E )-2-hexenal and ( Z )-3-hexen-1-ol contributed green, grassy and leafy aroma notes; while hydrogen sulfide, methyl thiirane, ( E,E )- bis -(1-propenyl) disulfide and ( E , Z )- bis -(1-propenyl) disulfide contributed pungent, sulfurous and alliaceous notes in TS.