Gui Anhui, Ye Fei, Xue Jinjin, Wang Shengpeng, Liu Panpan, Wang Xueping, Teng Jing, Feng Lin, Xiang Jun, Zheng Pengcheng, Gao Shiwei
Key Laboratory of Tea Resources Comprehensive Utilization (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Fruit and Tea Research Institute, Hubei Academy of Agricultural Sciences, Wuhan 430064, China.
Enshi Tujia and Miao Autonomous Prefecture Academy of Agricultural Sciences, Enshi 445002, China.
Foods. 2024 Dec 9;13(23):3968. doi: 10.3390/foods13233968.
Volatile constituents are critical to the flavor of tea, but the changes in Enshi Yulu tea during the processing have not been clearly understood. Using headspace solid phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME/GC-MS) techniques, we analyze the aroma components of Enshi Yulu tea and changes in them during the processing stages. In total, 242 volatile compounds were identified. From fresh leaves to the shaping process in tea production, there are significant decreases in overall aroma substances, followed by increases after drying. Linalool is the dominant aroma component in Enshi Yulu tea, with a proportion of 12.35%, followed by compounds such as geraniol (7.41%), 2,6-dimethyl-5-heptene (6.93%), phenylmethanol (5.98%), isobutyl acetate (4.16%), hexan-1-ol (3.95%), 2-phenylacetaldehyde (3.80%), and oct-1-ene-3-ol (3.34%). The number of differential volatile components varied by production stage, with 20 up- and 139 down-regulated after steaming, 24 down-regulated after rolling, 60 up- and 51 down-regulated after shaping, and 68 up- and 13 down-regulated after drying. Most variation in expression occurred because of steaming, and the least during the rolling stage. PLS-DA analysis revealed significant differences in aroma components throughout processing and the identification of 100 compounds with higher relative contents, with five distinct change trends. Phenylmethanol, phenylacetaldehyde, -non-2-enal, oct-1-ene-3-ol, and -3-hexenyl hexanoate could exert a profound influence on the overall aroma quality of Enshi Yulu tea during processing. The results offer a scientific foundation and valuable insights for understanding the volatile composition of Enshi Yulu tea and its changes during the processing.
挥发性成分对茶叶的风味至关重要，但恩施玉露茶在加工过程中的变化尚不清楚。采用顶空固相微萃取结合气相色谱 - 质谱联用（HS - SPME/GC - MS）技术，我们分析了恩施玉露茶的香气成分及其在加工阶段的变化。共鉴定出242种挥发性化合物。从鲜叶到茶叶生产中的造型过程，整体香气物质显著减少，干燥后增加。芳樟醇是恩施玉露茶中的主要香气成分，占比12.35%，其次是香叶醇（7.41%）、2,6 - 二甲基 - 5 - 庚烯（6.93%）、苯甲醇（5.98%）、乙酸异丁酯（4.16%）、己醇（3.95%）、2 - 苯乙醛（3.80%）和1 - 辛烯 - 3 - 醇（3.34%）等化合物。不同挥发性成分的数量因生产阶段而异，蒸青后有20种上调和139种下调，揉捻后有24种下调，造型后有60种上调和51种下调，干燥后有6种上调和13种下调。表达变化大多是由于蒸青引起 的，揉捻阶段变化最小。偏最小二乘法判别分析（PLS - DA）揭示了整个加工过程中香气成分的显著差异，并鉴定出100种相对含量较高的化合物，有五种不同的变化趋势。苯甲醇、苯乙醛、反 - 2 - 壬烯醛、1 - 辛烯 - 3 - 醇和己酸 - 3 - 己烯酯在加工过程中可能对恩施玉露茶的整体香气品质产生深远影响。这些结果为了解恩施玉露茶的挥发性成分及其在加工过程中的变化提供了科学依据和有价值的见解。
