Gyokuro

Gyokuro
Type	Green
Other names	玉露, jewel dew / jade dew / pearl dew / precious dew
Origin	Japan
Quick description	One of the highest grades of Japanese tea.

Gyokuro (Japanese: ^?, "jade dew") is a type of shaded green tea from Japan. It differs from the standard sencha (a classic unshaded green tea) in being grown under the shade rather than the full sun. Gyokuro also differs from another shaded tea called kabusecha (lit., "covered tea"), in the length of time it undergoes the final growth under the shade (gyokuro is shaded for approximately three weeks, while kabusecha is shaded for approximately one week). The name "gyokuro" translates as "jewel dew" (or "jade dew", referring to the pale green colour of the infusion). While most sencha is from the Yabukita (薮北^?) cultivar of Camellia sinensis, gyokuro is often made from a specialized variety such as Asahi, Okumidori, Yamakai, and Saemidori.

Gyokuro is prepared differently from other green teas:

Since gyokuro is typically steeped at such a low temperature, sources may recommend preheating both the pot and cup to maintain the warmth of the tea as one drinks it.

Though it is categorized as a type of sencha according to production methods, gyokuro cultivation differs from other sencha teas. Gyokuro tea leaves are shielded from the sun for at least 20 days with straw mats before being harvested. This causes both the amino acid theanine and the alkaloid caffeine in the tea leaves to increase, which yields a sweet flavour. The tea also gains a distinct aroma from the covering process. This type of cultivation is also used in producing tencha, (碾茶^?) but records indicate this process had already been developed in the Azuchi-Momoyama period.

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Wikipedia