采摘时期对重发酵单丛茶香气及理化品质影响研究

采用气相色谱-质谱(GC-MS)法对采自春、夏、暑、秋四个茶季的重发酵型单丛茶进行分析,研究重发酵单丛茶香气组分与理化品质随季节变化特点。结果表明:在不同采摘时期的重发酵单丛茶中,秋茶、春茶芳香物质种类相对较少(分别为41种和43种),香精油总量占总挥发性成分比例比夏茶低;而夏茶和暑茶芳香物质种类多(分别为45种和48种),香精油总量占总挥发性成分比例比秋茶高。夏、暑茶芳樟醇氧化物、杜松醇、律草烯等含量较高,而香叶醛、吲哚、茉莉酮、橙花叔醇等花香型香气成分含量比秋茶低得多。夏茶中芳樟醇及其氧化物的占总挥发性成分的比例明显高于其它季节的茶叶,达到69.77%,而春、暑、秋茶相应所占比例分别为50.98%、51.75%和51.72%。感官审评表明,秋茶、春茶单丛香气品质得分比夏茶、暑茶高,即秋茶、春茶香气品质要比夏、暑茶好。

Effect of Different Plucking Season on Aroma Constituents in Deep-Fermented Lingtoudancong Oolong Tea

The effect of different plucking season on aroma constituents in Lingtoudancong Oolong tea was investigated by gas chromatography and mass spectrometry analysis. Results showed that the tea which plucked in summer possessed more kinds of aroma constituents, higher total essential oil and lower concentration of flower aroma constituents. The tea plucked in spring and autumn possessed fewer kinds of aromatic constituents, lower amounts of essential oil, but with higher concentration of characteristic aroma constituents. The difference of characteristic aroma constituents expressed in the contents of linalool and linalool oxide in different plucking season. The tea plucked in autumn and spring seasons showed lower content of linalool and linalool oxide (50.98%～51.72%). However tea plucked in summer season showed a higher content of linalool oxide, cadinol and muurolene (more than 70.33%). The concentration of essential constituents such as α-citral, indole, jasmone and nerolidol are higher in autumn tea than those in other teas. The result of sensory evaluation showed that the sensory quality score of autumn tea is higher.