|
How Japanese Tea is Produced: Processing Japanese Green Tea
Japanese Tea is primarily green tea. Although small amounts of other types of tea are produced, the vast majority falls into the category of green tea, or "Ryokucha" in Japanese. In fact, many people in Japan do not differentiate "green" tea when talking about tea and often simply refer to it as "Ocha" (tea) or "Nihoncha" (Japanese tea).
The vast array of flavors in Japanese tea come primarily from their growing region, varietal of tea plant used, season of harvest and differences in the amount of sunlight the plants receive during growing.
Most Japanese teas are harvested and processed by specialized machines, even though it is still possible to find some specialized farmers who hand pick and hand process their teas. In flat, low lying areas, tractor-like harvesting machines are driven over the rows of tea plants, and in mountainous areas where tractors will not work, hand guided harvesters are usually used.
After harvest, the tea leaves are briefly steamed to deactivate the enzymes in the leaves that would otherwise oxidize and turn the leaves brown. Although traditionally steaming was done in paper lined bamboo trays over a large pot of boiling water, most modern steaming is done using a factory-style conveyor system which passes the tea leaves over or under a non-pressurized source of steam.
After steaming, the tea leaves were traditionally picked up and sprinkled down on the work surface to cool them quickly and begin the drying process, and the machines used in this step are made to mimic this hand tossing step in traditional processing. After the first cooling/drying, the tea is then rolled on rotary rolling machines to begin shaping the leaves and to evenly distribute the remaining moisture/plant juices in the leaves. After the first rolling, the tea is transferred to a drying machine to further reduce the residual moisture levels. Then the tea is rolled again to shape the leaves into their characteristic long needle like shape before the final drying.
After the final drying stage, the tea is known as Aracha, or unrefined/unsorted tea. Aracha contains all of the elements of the harvested tea plants, including the whole & broken leaves, leaf stems and twigs. At this point, the tea is fully processed and drinkable, and this is the point in processing that the tea is sold to the processors for refining. In the world of Japanese tea, freshness is absolutely paramount, so the processors put the Aracha into cold storage to keep it as close to fresh as possible. In this case, cold storage means the air is kept at just above freezing and humidity is strictly regulated to keep the leaves from losing their fresh, green appearance and flavor. The tea is then taken out of cold storage and processed to fill orders only as needed throughout the year.
Japanese tea processors use a fairly complex process of sorting and
refining the Aracha to achieve specific results in the finished cup of
tea. Sorting the leaves is a process of sifting and chopping the
Aracha. Sifting is done in a series of graduated colander-type screens
that sorts the Aracha into dust, fannings, stems, different sizes of
leaf, and so forth, while chopping breaks up any of the large leaves
into smaller, more uniform pieces. Many processors also use machines to further sort the tea, including
air-blowing sorting machines that can remove any old, dead, lightweight
leaves or woody stems, and other machines that employ cameras to detect
color inconsistencies are often used to identify and remove any
non-uniform color leaves, etc.
Once the sorting is done, the tea leaves are then put through a final drying stage to remove all but a tiny amount of residual moisture from the leaves before packaging. Recently, many processors have been using the final drying stage as a convenient time to adjust the final flavor of their finished product with different amounts of light roasting, etc. In the case of some gyokuro and sencha, different processors will leave in (or even add) different amounts of bright green tea dust in the sorted & dried finished tea leaves to make the steeped tea liquor have a more deep green color, which is a very important physical attribute to many consumers and tea sellers.
Packaging is also done by machines which weigh and seal the finished teas into individual portions. One attractive innovation that is widely used in Japanese green tea packaging is the use of nitrogen flushing before sealing the various tea packages. In this process, pure nitrogen gas is pumped into the bags of green tea, which forces almost all of the environmental oxygen out of the packages before they are sealed. This extra step, although not always used, is quite beneficial to the shelf life of these delicate Japanese green teas because remaining oxygen in the packaging could negatively affect the fresh taste of the tea leaves through oxidation. In light of this fact, please keep in mind that it is best to consume Japanese green teas within approximately 30 days or less after opening in order to ensure the freshest & most flavorful cup.
|
