Studies on the chemical constituents of different varieties of black tea

This study reports chemical constituents of 28 varieties of tea imported from 15 different countries. Water extract, total ash and fiber ranged between 35.3 - 47.4, 4.,7 - 6.39 and 7.11 - 17.23 percent (w/w) respectively. These values correspond to the standards established by the International Standards Organization (ISO). Caffeine in all the varieties was at the lower side of the required value ranging from 1.08 - 2.38/100 g. Tannins varied between 5.9-11.9% (w/w). Tea merchants in Pakistan should import tea containing appreciably high amounts of Caffeine so that after blending, tea brands of good Caffeine contents may be produced.

R B QADRI ,ASKARI BEGUM ,KHALID JAMIL ,SADIQA SHAKIR ,ABDUL ALI ,