Wang Feiquan, Feng Hua, Zheng Yucheng, Liu Ruihua, Dong Jiahao, Wu Yao, Chen Shuai, Zhang Bo, Wang Pengjie, Yan Jiawei
College of Tea and Food Science/Tea Engineering Research Center of Fujian Higher Education, Wuyi University, Wuyishan 354300, China.
College of Tea and Food Science/Tea Engineering Research Center of Fujian Higher Education, Wuyi University, Wuyishan 354300, China; College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
Food Res Int. 2025 Feb;201:115681. doi: 10.1016/j.foodres.2025.115681. Epub 2025 Jan 6.
Green is no longer the only color used to describe tea leaves. As tea plants with different leaf colors-white, yellow, and purple-yield significant economic benefits, scholars are growing increasingly curious about whether these differently colored leaves possess unique aromatic characteristics. Headspace solid-phase microextraction (HS-SPME) combined with GC-MS was used to analyze the volatile metabolites of buds and leaves from 7 white-leaf tea plants, 9 yellow-leaf tea plants, 4 purple-leaf tea plants, and 7 normal (green) tea plants. A total of 125 aroma metabolites were identified. The aroma compounds of heterochromatic tea leaves and green-leaf tea were compared separately. It was found that white-leaf tea had the most upregulated compounds (63 up), mainly floral and fruity aromas, including nerol, Z-isogeraniol, and E-3-hexen-1-yl acetate. Purple-leaf tea had the most downregulated compounds (31 down), including β-myrcene, benzyl alcohol, and methyl salicylate, which are related to fresh and fruity aromas. According to variable importance in projection (VIP > 1) and a p-value < 0.05, a total of 40 differential compounds were detected, among which Z-3-hexenol, 1-nonanol, 2,4-di-tert-butylphenol, and 2,6,10,15-tetramethyl-heptadecane were common in all heterochromatic tea. The random forest model constructed using differential metabolites screened out five aroma metabolites, including Z-3-hexenyl isobutyrate, E-3-hexen-1-yl acetate, 2,4-di-tert-butylphenol, Z-jasmone, and Z-isogeraniol. These metabolites demonstrated high accuracy in the model (AUC = 1) and have the potential to serve as characteristic aroma compounds for distinguishing tea leaf colors.
绿色不再是描述茶叶的唯一颜色。随着具有不同叶色（白色、黄色和紫色）的茶树带来显著的经济效益，学者们越来越好奇这些不同颜色的叶子是否具有独特的香气特征。采用顶空固相微萃取（HS-SPME）结合气相色谱-质谱联用（GC-MS）技术，对7株白叶茶树、9株黄叶茶树、4株紫叶茶树和7株普通（绿色）茶树的芽和叶中的挥发性代谢产物进行了分析。共鉴定出125种香气代谢产物。分别比较了异色茶叶和绿叶茶的香气化合物。结果发现，白叶茶上调的化合物最多（63种上调），主要为花香和果香，包括橙花醇、Z-异香叶醇和E-3-己烯-1-基乙酸酯。紫叶茶下调的化合物最多（31种下调），包括与清新果香相关的β-月桂烯、苯甲醇和水杨酸甲酯。根据变量投影重要性（VIP>1）和p值<0.05，共检测到40种差异化合物，其中Z-3-己烯醇、1-壬醇、2,4-二叔丁基苯酚和2,6,10,15-四甲基十七烷在所有异色茶中都很常见。利用差异代谢产物构建的随机森林模型筛选出5种香气代谢产物，包括异丁酸Z-3-己烯酯、E-3-己烯-1-基乙酸酯、2,4-二叔丁基苯酚、Z-茉莉酮和Z-异香叶醇。这些代谢产物在模型中显示出高准确性（AUC=1），有潜力作为区分茶叶颜色的特征香气化合物。
