Decaffeination this trait could be bred into other coffee plants by crossing them with "C. charrieriana", or an equivalent effect could be achieved by knocking out the gene for caffeine synthase in normal coffee plants. Tea may also be decaffeinated, usually by using processes analogous to the direct method or the CO process, as described above. The process of oxidizing tea leaves to create black tea ("red" in Chinese tea culture) or oolong tea leaves from green leaves does not affect the amount of caffeine in the tea, though tea-plant subspecies (i.e., "Camellia sinensis sinensis" vs. "Camellia sinensis assamica") may differ
History of tea the Chinese monopoly on tea. ""Camellia sinensis" originated in southeast Asia, specifically around the intersection of latitude 29°N and longitude 98°E, the point of confluence of the lands of northeast India, north Burma, southwest China and Tibet. The plant was introduced to more than 52 countries, from this 'centre of origin'." On morphological differences between the Assamese and Chinese varieties, botanists have long asserted a dual botanical origin for tea; however, statistical cluster analysis, the same chromosome number (2n=30), easy hybridization, and various types of intermediate hybrids and spontaneous polyploids all appear to demonstrate a single place of origin for