Zeng Lanting, Zhou Ying, Fu Xiumin, Mei Xin, Cheng Sihua, Gui Jiadong, Dong Fang, Tang Jinchi, Ma Shengzhou, Yang Ziyin
Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Xingke Road 723, Tianhe District, Guangzhou 510650, China; University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China.
Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Xingke Road 723, Tianhe District, Guangzhou 510650, China.
Food Chem. 2017 Dec 15;237:488-498. doi: 10.1016/j.foodchem.2017.05.137. Epub 2017 May 29.
The raw materials used to make oolong tea (Camellia sinensis) are a combination of leaf and stem. Oolong tea made from leaf and stem is thought to have a more aromatic smell than leaf-only tea. However, there is no available evidence to support the viewpoint. In this study, sensory evaluation and detailed characterization of emitted and internal volatiles (not readily emitted, but stored in samples) of dry oolong teas and infusions indicated that the presence of stem did not significantly improve the total aroma characteristics. During the enzyme-active processes, volatile monoterpenes and theanine were accumulated more abundantly in stem than in leaf, while jasmine lactone, indole, and trans-nerolidol were lower in stem than in leaf. Tissue-specific aroma-related gene expression and availability of precursors of aroma compounds resulted in different aroma distributions in leaf and stem. This study presents the first determination of the contribution of stem to oolong tea aroma.
用于制作乌龙茶（茶树）的原料是叶片和茎的组合。由叶片和茎制成的乌龙茶被认为比仅用叶片制成的茶具有更浓郁的香气。然而，目前尚无证据支持这一观点。在本研究中，对干乌龙茶及其冲泡液的挥发性成分（不易挥发但存在于样品中）和内部挥发物进行感官评价和详细表征，结果表明茎的存在并未显著改善总体香气特征。在酶活性过程中，挥发性单萜和茶氨酸在茎中的积累量比在叶片中更丰富，而茉莉内酯、吲哚和反式橙花叔醇在茎中的含量低于叶片。组织特异性香气相关基因的表达以及香气化合物前体的可用性导致了叶片和茎中香气分布的差异。本研究首次确定了茎对乌龙茶香气的贡献。
