Characterization of the Key Aroma Compounds in Three Truffle Varieties from China by Flavoromics Approach

The volatile compounds of three different fresh-picked truffle varieties (Tuber sinensis, T1, Tuber sinoalbidum, T2 and Tuber sinoexcavatum, T3) were extracted by headspace solid-phase microextraction (HS-SPME). Separation and identification of volatile components and sulfur compounds were investigated by gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC–MS) and gas chromatography with flame photometric detection (GC-FPD). The results showed that 44, 43 and 44 volatile compounds were detected in T1, T2 and T3 samples, respectively. In addition, 9, 10 and 9 sulfur compounds were identified in three samples by GC-FPD, respectively. Combining physicochemical and sensory properties, T1 presented fatty, green and rotten cabbage odor; T2 exhibited mushroom, sulfuric and musty odor notes; T3 had nutty, floral and roasted potato odor. Dimethyl sulfide, 3-methylbutanal, dimethyl disulfide, 3-octanone, bis(methylthio) methane, octanal, 1-octen-3-one, 1-octen-3-ol and benzeneacetaldehyde played indispensable roles in the overall aroma of three truffles. Finally, based on quantitative concentration in T1, odorous compounds (OAV) > 1 were mixed to recombine aroma, demonstrating that these key aroma compounds based on OAV can successfully recombine pretty similar aroma of each variety.