Regional features of the formation of the antioxidant properties of black tea

The article considers the influence of the region of origin of black tea on the formation of its antioxidant properties. The study involved samples of black tea, coming to the retail trade of St. Petersburg from Indian, Ceylon, Chinese and Kenyan. Significant differences were found in the quantitative composition of individual antioxidants in black tea samples, depending on the region of growth, both in the dry tea leaf and in the infusion. Water-soluble extractives in dry tea leaves and infusion prevailed in Ceylon tea. Tannin prevailed in Indian tea, and total phenolic compounds and flavonoids in Kenyan. The maximum transition of tannins in the infusion occurred in Kenyan tea, which accounted for 97.9% of its content in dry tea leaves. The higher brewing temperature of black tea increased the extraction of individual antioxidants. Black tea, depending on the region of origin, was distributed according to the content of total phenolic compounds and flavonoids as follows: Kenyan tea samples > Chinese tea samples > Indian tea samples > Ceylon tea samples...