Comparison of Catechins, Aroma Components and Sensory Quality of Different Types of White Tea

White tea is a unique kind of micro-fermented tea in China. In order to explore the quality differences of different types of white tea, ten samples including Baihaoyinzhen, Baimudan, Gongmei, Shoumei and New White tea were selected for high performance liquid chromatography (HPLC) detection of catechins, gas chromatography-mass spectrometry (GC-MS) detection of aroma components and sensory evaluation, combining with multivariate statistical analysis such as analysis of variance and OPLS-DA. The results showed that the content of catechins in different types of white tea varied greatly, the total catechin content of Gongmei was the highest and that of Shoumei was the lowest, which were 66.84 and 32.66 mg/g respectively, and a total of fifty aroma substances were detected in all white tea, the main aroma components consisted of hexanal, (E)-2-hexenal, benzaldehyde, linalool and its oxides (I, II). The aroma composition and content of Baihaoyinzhen, Baimudan, Gongmei and Shoumei were different from those of the New White tea. Among them, eight aroma components such as (E)-2-pentenoaldehyde and 2-heptanone existed in a large number in the four traditional white tea, but they were not detected in the New White tea. Through multi-component chemometric analysis, it was found that there were significant differences in catechins and aroma metabolites between Baihaoyinzhen, Baimudan, Gongmei and New White tea, but there was little difference between Shoumei and New White tea. This study preliminarily proved the quality differences of different types of white tea, which provided a theoretical basis for the regulation of white tea flavor quality.