关键词: 尤溪苦茶, 苦涩味, 生物碱, 儿茶素

Abstract: This study determined the bitter and astringent substances, such as anthocyanins, total flavonoids, alkaloids and catechins in 33 samples of Youxi bitter tea leaves by ultraviolet spectrophotometry and high performance liquid chromatography (HPLC). The results showed that all characteristic components tested varied among samples, and the variation coefficients of 20 of these indicators varied from 9.74% to 73.08%, indicating the rich diversity and high variability of bitter and astringent compounds in Youxi bitter tea. Compared with four control teas, the average values of anthocyanins, caffeine, theobromine, theophylline, epigallocatechingallicacid, total catechins and ester catechins were found to be higher in Youxi bitter tea, providing preliminary evidence that the distinct bitterness and astringency of Youxi bitter tea is related to the high contents of anthocyanins, caffeine and catechins and their synergistic effects. This study then screened out one anthocyanin-rich sample, one caffeine-rich sample, one theobromine-rich sample and 21 EGCG-rich samples. This study provides a good material basis for future research on cross-breeding, processing innovation, functional components and secondary metabolism of bitter tea.

Key words: Youxi bitter tea, bitterness and astringency, alkaloids, catechin