Identification and characterization of key aroma compounds in Chinese high altitude and northernmost black tea (Camellia sinensis) using distillation extraction and sensory analysis methods

Abstract The studied Chinese northernmost black tea made of the tea leaves harvested at high altitude and low climatic temperature location and special tea manufacturing process presented strong honey‐like, moderated green/grass and weak floral and fruity aromas. Its aroma was significantly different from other black tea. The key compounds responsible for these aromas were identified and quantified by gas chromatography‐mass spectrometry (GC‐MS), gas chromatography‐olfactometry (GC‐O), aroma extract dilution analysis (AEDA), aroma reconstitution and exclusion experiments methods. A total of fifty‐eight aroma compounds were found in the black tea. Among them, phenylacetaldehyde, E ‐2‐hexenal, E , E ‐2,4‐nonadienal, 2‐methylbutanoic acid ethyl ester, β‐ionone, linalool, α‐ionone and geraniol were mainly responsible for the black tea aroma. They offered honey‐like, floral, green/grassy, violet‐like and fruity aromas in the tea infusion. Although E , Z ‐2,6‐nonadienal was one of the major volatile compounds, its unique cucumber‐like odour was not perceived in the tea fusion. The special growing location and processing for the tea leaves may contribute to the unique aroma of the black tea.