不同茶树品种与加工工艺对黄茶香气形成的影响

Study on the Effects of Different Tea Plant Cultivars and Processing Technology on Aroma Formation of Yellow Tea

为探究黄茶香气形成的影响因素,本试验对采用不同茶树品种加工、不同摇青时间和不同焙火温度加工而成的黄茶进行香气物质测定。结果发现:同一工艺条件下,四个不同茶树品种的香气物质中均以醛类和醇类含量较高,但其主要香气物质含量和组成有一定差异进而造成最终香型的差异;此外,‘御金香’品种黄茶的含氮化合物高于其他茶树品种,达23.17%,是其他品种的三倍,这可能与该品种春季氨基酸含量高相关。以‘御金香’品种鲜叶为试材,对其进行摇青和焙火处理,发现不同摇青时间处理的‘御金香’黄茶也是以呈现“花果香”的醇、醛类和烃类物质为主,其中烃类(14.51%、17.02%、18.71%)会随摇青时间增加呈增长趋势,醇类(14.66%、14.00%、10.43%)、醛类(49.93%、41.06%、42.24%)会有一定程度下降。而经过焙火后的‘御金香’黄茶,烃类含量大幅增加,均值达到40%左右,而对该茶样起主要贡献作用的含氮化合物(4.46%、6.02%、7.15%、8.70%)与含氧化合物(13.99%、15.00%、18.58%、14.54%)也随焙火温度上升呈现不同幅度的增加。

In order to explore the influencing factors of yellow tea aroma formation,the aroma components of yellow tea processed by different tea cultivars,different rotating time and different baking temperature were determined.It was found that under the same process,the contents of aldehydes and alcohols in the aroma components of four different tea cultivars were higher,However,there are some differences in the content and composition of the main aroma componentss,resulting in the difference of the final aroma type.Secondly,it is found that the nitrogen-containing compounds of Yujinxiang yellow tea are higher than other varieties,up to 23.17%,which is three times that of other cultivars,which may be related to the high content of amino acids in spring.The fresh leaves of Yujinxiang were treated with rotating and baking.It was found that the Yujinxiang yellow tea treated with different rotating time was also dominated by alcohols,aldehydes and hydrocarbons with‘flower and fruit aroma’,in which hydrocarbons(14.51%,17.02%,18.71%)increased with the increase of rotating time,alcohols(14.66%,14.00%,10.43%),aldehydes(49.93%,41.06%,42.24%)decreased to a certain extent.After baking,the content of hydrocarbons in Yujinxiang yellow tea increased significantly,with an average of about 40%,and the nitrogen-containing compounds(4.46%,6.02%,7.15%,8.70%)and oxygen-containing compounds(13.99%,15.00%,18.58%,14.54%)that played a major role in the tea sample also increased by varying degrees with the rise of baking temperature.