Abstract: ‘Jinmudan’ (Camellia sinensis ‘Jinmudan’) is an excellent high-flavor variety cultivated extensively across the country. Currently, research on ‘Jinmudan’ varieties tea primarily focused on the aroma quality of Jinmudan spring tea, with limited studies on the quality of summer and autumn teas and their multi-tea. In this study, the tender shoots of ‘Jinmudan’ tea plant in summer and autumn were processed into green tea, yellow tea, white tea, oolong tea and black tea respectively. Headspace solid phase microextraction-gas chromatography-mass spectrometry was used to determine and analyze the volatile metabolites in 5 kinds of tea in summer and autumn. The results showed that 522 volatile metabolites were identified in summer tea, mainly terpenes, esters and alcohols, and 502 volatile metabolites were identified in autumn tea, mainly terpenes, esters and heterocyclic compounds. The analysis of aroma activity value showed that β-ionone, α-ionone, γ-decanolactone and geraniol were the key aroma substances of Jinmudan green tea, while 2-ethoxy-3-methylpyrazine, decanal, methyl benzoate and dehydrolinalool were the key aroma substances of Jinmudan yellow tea. Geraniol, phenylacetaldehyde, methyl salicylate and benzyl alcohol are the key fragrance substances of Jinmudan white tea. Indole, 2-pentylfuran, α-farnesene and (E)-linalool oxide are the key aroma substances of Jinmudan oolong tea, while geraniol, β-ocimene, linalool and 4-methoxybenzaldehyde are the key aroma substances of Jinmudan black tea. The contribution, variety and quantity of aroma substances in autumn tea were more than those in summer tea. Among them, the OAV values of 42 key aroma substances such as geraniol, methyl salicylate and phenylethanol in autumn were higher than those in summer. On the whole, the flower aroma is the main aroma type of Jinmudan tea, and the aroma quality of autumn tea is better than that of summer tea. 14 volatile metabolites such as geraniol, linalool, 2-ethoxy-3-methylpyrazine and methyl benzoate are the key aroma substances of Jinmudan tea varieties.

Key words: Jinmudan (Camellia sinensis ‘Jinmudan’), different types of tea, summer-autumn tea, aroma quality, Odor activity value (OAV)