Phenolic Compounds of Krasnodar Tea

Author(s): Oksana Belous, Nataliia Platonova

The quality of the finished tea depends on the composition of the substances that make up the raw material (2 or 3 leaves). Extractive substances are the main components that determine the taste and aroma of tea. An equally important role is played by alkaloid containing substances – caffeine, theobromine and theophylline (Leong, et al., 2001; Valiulina, Makarova, 2018; Wright, 2002; Chowdhury, et al., 2018; Zeyi Ai, et al., 2017). From alkaloid-containing compounds during the growing season, mainly caffeine is formed and accumulated (2-3%). Tea leaves, both fresh and processed, contain pigments (chlorophyll, carotenoids, anthocyanins, flavonoids), on which the color of tea depends. The quantitative content of flavonoids is one of the indicators of the quality of tea (Wan et al., 2015; Potapovich A. I., Kostyuk, 2003; Ivanova et al., 2017; Zaprometov, 1993). Therefore, for the primary assessment of the quality of plant raw materials, quantitative determination of the content of flavonoids is often used. The metabolism of tea plants is based on the processes of accumulation and transformation of tannins (catechin complex, mainly (-)-epigallocatechingallate), the content of which reaches 30% or more. Tannins, namely teotanin, are a complex mixture of the Gallic esters of catechins and the catechins themselves. Oxidized teotanin gives the tea infusion a yellow-brown or reddish color, astringency, and taste.