Wang Zhihui, Wang Zhihua, Dai Haomin, Wu Shaoling, Song Bo, Lin Fuming, Huang Yan, Lin Xingchen, Sun Weijiang
College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou, China.
Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, Fujian Agriculture and Forestry University, Fuzhou, China.
Front Nutr. 2022 Dec 19;9:1092048. doi: 10.3389/fnut.2022.1092048. eCollection 2022.
Compressed white tea (CWT) is a reprocessed tea of white tea. Long-term storage has greatly changed its aroma characteristics, but the material basis and transformation mechanism of its unique aroma are still unclear. In this study, flavor wheel, headspace gas chromatography ion mobility spectroscopy, chemometrics, and microbiomics were applied to study the flavor evolution and important aroma components during long-term storage of CWT, and core functional bacteria were screened. During long-term storage, the aroma of CWT gradually changed from sweet, fruity and floral to stale flavor, woody and herbal. A total of 56 volatile organic compounds (VOCs) were identified, 54 of which were significantly differences during storage. The alcohols content was the highest during 1-5 years of storage, the esters content was the highest during 7-13 years of storage, and the aldehydes content was the highest during 16 years of storage. Twenty-nine VOCs were identified as important aroma components, which were significantly correlated with 6 aroma sub-attributes ( < 0.05). The functional prediction of bacterial community reminded that bacterial community could participate in the transformation of VOCs during storage of CWT. Twenty-four core functional bacteria were screened, which were significantly associated with 29 VOCs. Finally, 23 characteristic differential VOCs were excavated, which could be used to identify CWT in different storage years. Taken together, these findings provided new insights into the changes in aroma characteristics during storage of CWT and increased the understanding of the mechanism of characteristic aroma formation during storage.
紧压白茶（CWT）是白茶的再加工茶。长期储存使其香气特征发生了很大变化，但其独特香气的物质基础和转化机制仍不清楚。本研究应用风味轮、顶空气相色谱离子迁移谱、化学计量学和微生物组学研究了紧压白茶长期储存过程中的风味演变和重要香气成分，并筛选了核心功能细菌。在长期储存过程中，紧压白茶的香气逐渐从甜香、果香和花香转变为陈味、木香和草香。共鉴定出56种挥发性有机化合物（VOCs），其中54种在储存过程中有显著差异。储存1 - 5年期间醇类含量最高，储存7 - 13年期间酯类含量最高，储存16年期间醛类含量最高。29种VOCs被鉴定为重要香气成分，与6种香气子属性显著相关（<0.05）。细菌群落的功能预测表明，细菌群落可能参与紧压白茶储存过程中VOCs的转化。筛选出24种核心功能细菌，它们与29种VOCs显著相关。最后，挖掘出23种特征性差异VOCs，可用于鉴别不同储存年份的紧压白茶。综上所述，这些发现为紧压白茶储存过程中香气特征的变化提供了新的见解，并加深了对储存过程中特征香气形成机制的理解。
