Abstract: The volatile components of green tea samples with three different typical chestnut-like aromas were investigated using headspace solid phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOFMS). The key odorants responsible for chestnut-like aroma were identified based on their odor activity values (OAV). The results showed that a total of 79 compounds were identified as common components among the three chestnut-like aromas, the majority of which were terpenes, while aldehydes showed the highest content. Moreover, 12 compounds with OAV ≥ 1 were identified as the key odorants responsible for the chestnut-like aromas, among which hexanal, 1-octen-3-one and trans-β-ionone exhibited higher OAV (≥ 10). Notably, 1-octen-3-one showed the highest OAV ( > 100) in all three chestnut-like aroma types. In addition, based on the OAV results, the key aroma components added at the same concentrations and ratios to the simulation system for aroma reconstitution. The cosine values of reconstituted samples and standard references for the three typical chestnut-like aromas were all above 0.97. The contribution of 12 key aroma components to the characteristic aroma of chestnut-like green teas were preliminarily confirmed, and the reliability was further confirmed by aroma reconstitution experiments. The results provide theoretical support for qualitatively and quantitatively evaluating green tea aroma compounds.

Key words: headspace solid phase microextraction, comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry, green teas with chestnut-like aroma, odor activity value