Sensomics-Assisted Characterization of Fungal-Flowery Aroma Components in Fermented Tea Using <i>Eurotium cristatum</i>
Shanshan Shen, Jixin Zhang, Haoran Sun, Zhongqi Zu, Jialin Fu, Ranqin Fan, Qi Chen, Yu Wang, Pengxiang Yue, Jingming Ning, Liang Zhang, Xueling Gao
Abstract
Fermented tea (FT) using a single Eurotium cristatum strain can produce a pleasant fungal-flowery aroma, which is similar to the composite aroma characteristic of minty, flowery, and woody aromas, but its molecular basis is not yet clear. In this study, solvent-assisted flavor evaporation and gas chromatography–mass spectrometry/olfactometry were applied to isolate and identify volatiles from the FT by E. cristatum . The application of an aroma extract dilution analysis screened out 43 aroma-active compounds. Quantification revealed that there were 11 odorants with high odor threshold concentrations. Recombination and omission tests revealed that nonanal, methyl salicylate, decanoic acid, 4-methoxybenzaldehyde, α -terpineol, phenylacetaldehyde, and coumarin were the major odorants in the FT. Addition tests further verified that methyl salicylate, 4-methoxybenzaldehyde, and coumarin were the key odorants for fungal-flowery aroma, each corresponding to minty, woody, and flowery aromas, respectively. 4-Methoxybenzaldehyde and coumarin were newly found odorants for fungal-flowery aroma in FT, and 4-methoxybenzaldehyde had not been reported as a tea volatile compound before. This finding may guide future industrial production optimization of FT with improved flavor.