Effect of altitude, shooting period, and tea grade on the catechins, caffeine, theaflavin, and thearubigin of Turkish black tea

The effect of altitude, shooting period, and tea grade on the catechins and caffeine contents of Turkish black tea was investigated. The experimental factors significantly affected all of the parameters analyzed. Epigallocatechin gallate was the major catechin of black tea (0.719-1.007 g 100 g(-1) dm) followed by epigallocatechin (0.627-0.791 g 100 g(-1) dm). Additionally, caffeine (1.810-2.175 g 100 g(-1) dm), theaflavin (3.201-6.000 mu mol g(-1)), and thearubigin (8.577-12.635 g 100 g(-1) dm) contents were determined. Samples of tea grown at high altitude generally produced a considerably greater amount of the catechins that improve tea quality. Shooting period, which is specific to tea cultivation in Turkey, significantly affected almost all of the quality parameters of black tea. Tea produced in the first shooting period contained more catechins than the samples plucked in the following shooting periods. Dust and orange pekoe 1 contained the most catechins of the tea grades analyzed.