Defining key characterized aroma components in Chinese black teas with different aroma types based on sensoromics

Different types of black tea appeal to consumers for their unique flavors. This study employed solvent-assisted flavor evaporation combined with solid-phase microextraction and gas chromatography-olfactometry-mass spectrometry to explore key characteristic compounds in multiple black tea varieties, including sweet, peach, sweet floral, cool, and sweet potato aroma attributes. A total of 30 common aroma-active components were identified across all aroma groups with modification frequency > 30%, among which 17 exhibited odor activity values of ≥1. Further aroma recombination simulations were conducted based on these compounds. Simultaneously, omission experiments revealed that 7, 8, 7, 5 and 10 aroma compounds, respectively, were particularly crucial for aroma formation in the sweet, peach, sweet floral, sweet potato and cool groups. These substances include: linalool, linalool oxide (furan), phenethyl alcohol, geraniol, phenylacetaldehyde, hexanal, heptanal, nonanal, coumarin, methyl jasmonate, δ- decanolactone, β- ionone, 6-methyl-5-hepten-2-one, cis-Jasmone, methional, and indole. Among these, δ- decanolactone and methional appear exclusively in the key aroma compounds of the sweet flavor; indole and methyl jasmonate are present only in the key aroma compounds of the peach flavor; nonanal occurs solely in the characteristic aroma of sweet potato flavor; while 6-methyl-5-hepten-2-one was exclusively found in the key aroma compounds of the cool aroma. This discovery offers new insights into enriching the aromatic characteristics of black tea and provides additional options for producing black teas with distinct flavor profiles.