Sencha is the most popular tea in Japan, accounting for almost 80% of the tea consumed. Usually the top parts of tea leaves and buds are used to produce Sencha. It is grown in full sunlight and is processed in multiple stages: steaming, kneading, drying, sifting, roasting and often blending. Sencha is noted for its delicate sweetness, mild astringency and flowery-green aroma.
What determines the flavor of Sencha?Sencha is the most popular tea among Japanese teas, but not all Senchas are the same. The quality and taste of Sencha will vary depending on the following factors ‐ growing area, tea cultivar, harvest season, manufacturing process, and brewing technique. Generally these factors also apply to the other teas.
Growing AreaThe area in Japan where the tea is grown is the first element affecting the taste. There are some famous Sencha tea producing areas in Japan ‐ (from north to south) Sayama, Shizuoka, Uji, Kagoshima, Yame and so on. As with other agriculture, the different areas have different weather and soil resulting in different flavors.
Tea CultivarWhile all tea is made from the same tree, Camellia Sinensis, there are a number of varieties as an apple has varieties like Pink Lady, Fuji or Granny Smith. In Japan, 108 cultivars have been registered for Camellia Sinensis likeYabukita, Yutaka‐Midori, Sayama‐Kaori, Kanaya‐Midori and so on, and sometimes the name is used for its product itself. Yabukita is widely used, accounting for 80% of Japanese tea production because Yabukita has been popular since it has very good flavor and is resistant to diseases. Each breed produces a leaf with a different shape, color and flavor.
Harvest SeasonThe harvest season is also a big factor affecting quality. The best quality green teas are produced in the 1st flush or harvest in Japan. For the 2nd and 3rd flush, the quality becomes lower.
The tea plant is hardy with lots of energy and there are generally 3 to 4 harvests during the picking season. In April or May, new buds are flushed when the weather becomes warm. After the first harvest, new buds reappear in about a month. There is another harvest and the cycle repeats itself. There is only a month or so between each flush until autumn. During the winter the plants go dormant and during this hibernation the tea tree builds up much nutrition from the land. In the spring, the first new buds have all the nutrition from the 6 winter months and they are full of flavor. That's why the first flush tea is the best quality.
In some unique tea gardens they only produce premium Sencha. They pick first flush tea and then the tea bush is cut back so it cannot flush new buds again during that season. The following year, the new leaf has nutrition from a year and obviously has a lot of flavor.
Manufacturing ProcessWhile there are several processes in producing Sencha, roasting and blending are the most important ones in determining flavor. Blending stabilizes the quality. There are many types of the leaves ‐ one has good flavor, one has good taste, and the other has good color and shape. An experienced tea‐taster specifies the blend for harmonious taste, flavor and color.
Roasting is another process much like roasting coffee. Note that this roasting process is not a deep roasting as for Houjicha, it is more like a light roasting to add a nutty flavor to the grassy green tea flavor. Each company has its favorite roasting technique from weak to strong and it is up to your taste. You probably have experienced that some Senchas taste very grassy while some are robust and you're not sure which is best. The roasting does not determine the quality of tea so the best one is the flavor you like.
Brewing techniqueBrewing loose tea like Sencha takes a little more care than pouring boiling water over a tea bag. Here are two videos which demonstrate a good technique for brewing sencha.