In some ways, not much has changed with the Tsuen tea shop, the world's oldest continually operating tea shop since 1160 A.D. Located at the same location on the east side of the Uji Bridge in Uji Japan, 24 generations of the Tsuen family have served green tea to the many travelers, monks, samurai, shoguns, and now tourists that cross this important bridge between Kyoto and Nara.
In 1160, the first ancestor of Tsuen family and aslo the founder of Tsuen tea, Furukawa Unai, was a samurai who worked for Minamoto Yorimasa. Furukawa retired, then changed his name to “Taikeian Tsuen Masahisa”. “Taikeian” is the name of building where Zen monks or other people go when they are trying to achieve enlightenment. “Tsuen” means Tsu – way or path and “En” means circle, round, or calm and En is a word from Zen. “Masahisa” took his name from the Chinese character “Masa” which is the first name from his master, Minamoto Yorimasa. It was the start of Tsuen Masahisa’s new life. He then became a guardian for the Uji Bridge.
The 10th and 11th Tsuens were charged with supplying water for tea for the famed Shogun Toyotomi Hideyosh who is regared as Japan’s second “great unifier”. Since then, the Tsuen family has served tea on the same spot for 23 generations. Ryōtaro Tsuen is the current owner and Yūsuke Tsuen is the 24th generation of this family to serve Japan’s most famous tea in the country’s oldest teashop. In 2003 Tsuen Tea opened an International Office in Vancouver, Canada.
Tsuen organic teas are certified by JONA, the certification body of the Minister of Agriculture, Forestry and Fishery. In addition, Tsuen teas that are not organic undergo strict tests to meet the guidelines of the Japanese government: each individual tea field is scientifically tested to maintain health safety standards. The two basic methods of growing Japanese tea are in the shade and in the sun. Shaded tea is covered with a straw or cheesecloth several weeks before harvest. This gives the tea a milder flavour. The kinds of tea grown in this manner are: Gyokuro, Kabusecha and Tencha. Tencha is later stone-milled into Matcha. Non-shaded teas are stronger tasting. The teas grown this way are : Sencha, Genmaicha and Hojicha.
According to tsuentea and en.wikipedia