Green tea is first discovered and used by our ancestors. It is also the most productive and most widely-consumed, known as the "national drinks." There are numerous famous brands of green tea, such as West Lake Longjing, Biluochun, Huangshan Maofeng and so on. Green tea is of the gentle and reserved nature, and the liquid is clean and chilly with quiet fragrant aroma, giving people a green and quiet enjoyment. It is ideal for sips. What's more, green tea has more significant health effects than other kinds of tea.
Green teas are often referred to as "non- fermented" or "unfermented" teas. The freshly picked leaves are allowed to dry, then are heat-treated to stop any fermentation (or oxidation) that would rot the leaf. In China, traditional hand-making methods are still employed in many places, particularly in the manufacture of China's finest teas, but some factories have introduced a mechanized process. By the traditional method, the fresh green leaves are spread out in a thin layer on bamboo trays and exposed to sunlight or natural warm air for one or two hours. The leaves are then placed, a small amount at a time, into hot roasting pans and moved about quickly with the hands, as they become moist and soft and the natural moisture evaporates. (A small amount of China’s green teas are steamed rather than roasted). After four or five minutes, the softened leaves are rolled into balls on bamboo tables (in the larger factories, this was traditionally done with the feet) and the tea balls are then again placed almost immediately into the hot roasting pans and moved about rapidly before being rolled for a second time or being left to dry. After one or two hours, the leaves have turned a dull green and undergo no further change.
They are finally sifted to separate them into different-size pieces of leaf.
In Japan, the plucked leaves are steamed quickly on a moving belt, making them supple and soft ready for rolling. They are cooled and then repeatedly rolled, twisted, and dried until all the moisture has evaporated. A final rolling stage shapes and styles the leaves before the last drying period. The tea is then allowed to cool before being packed into airtight containers for shipment to retail stores. Some Japanese teas are still processed by hand, although most factories are now mechanized.
Green teas are generally described as 'unoxidized' teas and no chemical change occurs during their manufacture. Processing differs from country to country but the basic manufacture sometimes involves a short period of withering to allow some of the water content in the leaf to evaporate, then steaming or pan-firing, to de-enzyme the leaf. Next comes a series of rollings and firings to shape and dry the leaf. Sometimes, the leaf is alternately rolled or shaped by hand, giving each tea its own characteristic appearance - for example, the tiny pellets of Gunpowder, the curved eyebrow shape of Chun Mee (Precious Eyebrows), or the tightly wound spirals of Biluochun (Green Snail Spring). After shaping, or sometimes as the shaping process is taking place, the teas are dried in wok-like pans, in closed ovens, on baskets or cloths set over charcoal fires or in tumble dryers. Methods of shaping and drying vary from country to country and region to region. In many parts of China, Korea and Vietnam, for example, the teas are hand-crafted, sometimes with the help of some simple machinery, and the skills involved in making the teas are passed on from one generation to the next. In other producing regions, the manufacturing process has been totally mechanized or automated. In Japan, for example, the entire process for most teas is entirely mechanized and the leaves are first steamed on a rapidly moving conveyor belt to make them soft and supple, then mechanically cooled and repeatedly rolled, pressed, sorted, polished and dried before being cooled again and packed at the end of the production line.
The quality features of the green tea are Three Greens, namely green leaves, green soup, and green brewed leaves.
Green tea is the earliest unfermented tea processed by human. Its most obvious features are the green soup and green leaves. The dry tea leaves are green and the tea soup is bright yellowish green. The brewed tea leaves (tea dregs) are fresh green.
The green tea has the most varieties. Its output is the highest among all teas. It is produced in the widest areas. Almost all tea-producing areas in China produce green tea.
Producing green tea will normally go through three processing procedures: fixation, rolling, and drying. Of them, fixation is the key procedure to decide the color of the green tea. During fixation, high temperature is applied to destroy the activity of the enzyme in the tea and stop the enzymatic oxidation of green tea polyphenol (GTP) substances. Through fixation, the tea leaves are dehydrated and their green odor is dispersed. As a result, tea aroma is created.
Based on fixation modes and final drying modes, green tea can be divided into four types: steamed green tea, stir fixation green tea, baked green tea, and sunned green tea. There is also the semi-baked and semi-stir-fixation green tea.
As green tea is not fermented, it contains large amount of the natural components of the fresh tea leaves, including over 85% of the GTP and caffeine. GTP in green tea is a compound composed of several phenol substances, mainly including catechin, flavone, anthocyanidin, and several phenolic acids. Of them, catechin content is the highest, accounting for over 70% of GTP. Catechin can enhance the activity of capillary vessel, prevent arteriosclerosis, stop diarrhea, kill bacteria, and reduce inflammation. In addition, green tea also contains rich amino acid and many elements and trace elements needed by human body, including phosphorus, calcium, potassium, sodium, magnesium, sulfur, iron, manganese, zinc, selenium, copper, fluorine, and iodine. These elements play an important regulating role in keeping physiological health of human body.
Though containing high content of nutrients, green tea is not necessarily suitable for all people. Traditional Chinese medicine regards green tea as cold in nature and is not suitable for the patients suffering from fever, liver diseases, neurosism, ulcer, and malnutrition, and women during gestation and lactation periods.
There are many famous green tea varieties, including the West Lake Longjing Tea, Biluochun Tea from Mt. Dongting, Yunwu Tea from Mt. Lushan, Maofeng Tea from Mt. Huangshan, Houkui Tea from Taiping, Zhuyeqing Tea from Mt. Emei, Ganlu Tea from Mengding, Maojian Tea from Xinyang, Zisun Tea from Mt. Guzhu, Buddha Tea from Mt. Putuo, Anji White Tea, Maojian Tea from Duyun, and Yuhua Tea from Nanjing.
Green tea, the most various and popular in China, and currently the type of tea most widely credited with amazing health benefits. Many Chinese drink nothing else. Our green tea leaves is made solely from the leaves of Camellia sinensis that have undergone minimal oxidation during processing. Green tea also contains caffeine but this is released slowly into the blood, giving you all the advantages of caffeine and not the disadvantages.
China overflows with famous green teas, including Long Jing, Bi Luo Chun, Anji Bai Cha and XinYang Mao Jian, to name but a few. Numerous traditional methods -handed down through centuries according to the customs of each region - have lead to a profusion of green teas, which today represent more than 70 percent of all Chinese production. The major growing regions are located in the south of the country, especially in provinces like Fujian, Zhejiang, Anhui, Henan, Jiangsu and Jiangxi.
Methods of picking vary greatly from one region to another Usually the leaves are picked when young (the bud plus one or two leaves), but there are exceptions to this rule. For example, more mature leaves are harvested to produce Tai Ping Hou Kui, and in the case of Lu An Gua Ran, only the leaves are picked and the bud is left on the stem.
Immediately after picking, the leaves are transported to the factory, where they will undergo the process of withering. Withering time will vary depending on the prevailing conditions and the water content of the leaves. The traditional method of withering is to spread the leaves on bamboo racks and leave them to dry for one to three hours in order to remove the surplus water. To prevent them from drying too rapidly, they are sometimes spread on cloths in the shade. The mechanical method involves placing the leaves in a cylindrical machine with bamboo walls, so that they "spin dry" for a few minutes while fans blow air through them.
It is important to note that, as soon as the leaves are picked, a natural chemical process causes oxydase, a process by which enzymes contained in the leaves react with oxygen in the air. Handling the leaves during the withering and rolling processes breaks down the leaves' cell structure, releasing the oils they contain, which, on contact with oxygen, trigger a chemical change in the leaves. In order to produce green tea, this natural process of oxidation must be interrupted. This is achieved through dehydration.
This is the process of heating the leaves until the enzymes that cause oxidation lose their potency. Methods vary according to the region and the customs of the individual grower. There are many ways to heat leaves. In China it usually involves the use of vats.
Small quantities of leaves are put in pans or vats that are heated with wood, coal or electricity. The leaves are pressed to the bottom of the vat and then constantly stirred so they don't burn. The leaves are processed in small batches. Next, different techniques are used according to the form the leaves are supposed to take. If the leaves are to be flat, as in the Long Jing variety, they are pressed to the bottom of the vat briefly before being stirred in a back-and-forth movement. If the type of tea is curly, like the Bi Luo Chun variety, they are rolled by hand and constantly stirred until they are dry. The heat of the vat can vary. At first the heat is low, but once the process is under way the heat is increased.
When the leaves are mechanically processed, they are heated at least three times in rotating cylinders. In between heating periods they are sometimes spread on cloths to cool. As the leaves are heated, a chemical process is triggered: the sugars and proteins they contain are transformed, giving the tea an aromatic quality that is sometimes reminiscent of grilled nuts. This stage also releases the polyphenols contained in the leaves.
Fixation comes first to produce green tea. Through high temperature and passivation of oxidation enzyme activities in fresh leaves, evaporate water in the fresh leaves to soften the tea leaves, and thus to roll tea leaves easily and to promote fragrance.
Generally there are two kinds of fixation: by heat and by steam. Green tea made of steam-fixation called steaming green tea, yet heat-fixation is used more often.
After fixation, the tea will be rolled repeatedly to a certain shape and promote the cell breakage of tea leaves, facilitating the seepage of tea leaves soluble in water.
This stage consists of rolling the leaves to break down their cell structure and release the aromatic oils they contain. Rolling, which is partly responsible for the taste and appearance of Chinese green teas, also changes the shape of the finished product, determining whether they will be twisted, flat, needle-shaped or bead-shaped leaves.
When processing is done by hand, rolling and dehydrating are part of a single process, as we have seen. In the case of mechanical processing, various machines are used to obtain curly or flat leaves.
There are fried drying, baked drying and sun drying. It is to evaporate excess moisture in tea leaves to keep the live enzymes in tea, and therefore it is easy to maintain tea quality and fix tea shape.
During this penultimate stage, the aromatic oils released during rolling become stabilized on the leaves. In addition, any remaining water is eliminated so there is no risk of mold. At the end of this process, only 2 percent to 4 percent moisture remains in the leaves.
Lastly, the leaves are sifted through a fine sieve to remove any that broke during processing. At this stage, the leaves are sorted into sizes by means of bamboo meshes of different sizes placed one on top of the other.
Flat tea: flat, level, straight, such as West Lake Longjing.
Bar-shaped tea: uniform shape and size, same tightness of tea strips, such as Xinyang Maojian.
Roundness tea: round and tight, such as Yongxi Huoqing.
Needle tea: tight and thin, round and straight, appearing as pine needle, such as Nanjing Yuhua tea.
Bud-shaped tea: tea, including buxus-shaped tea, such as Huangshan Maofeng. Sheet-shaped tea: flat and straight, full and uniform, flaky, such as Liu'an Guapian. Tip-shaped tea: straight strips stretching naturally, such as the Taiping Houkui.
The light green or light yellow green liquid, clear and bright is of fine quality. If it is yellow, too dark and cloudy, then it comes second.
With unique flavor, natural fragrance, and delicate, lingering flavor, green tea may sends out faint scent, tender scent, or floral scent.
Tea with fresh, mellow, and sweet aftertaste is better. That with bitter, light, and bad aftertaste is degraded.
Brewed tea leaves
The tea with bright green, light green, light yellow, bright colors, and uniform and homogeneous leaves is recognized as good. That in yellow and irregular color, with not enough brightness is inferior.
Green tea boutique
West Lake Longjing, Dongting Biluochun, Huangshan Maofeng, Xinyang Maojian, Lushan Yunwu, ，Nanjing Yuhua tea, Wuyuan green tea, Liu'an Guapian, Taiping Houkui, and Jingshan tea.
Effects of green tea
First, rich in theanine and catechin，it can delay aging and remove free radicals.
Second, polyphenols and their oxidation products in green tea are able to absorb poison of radioactive materials, and thus to help prevent cardiovascular diseases.
Third, it can prevent and treat radiation injury. Fourth, caffeine in tea can enhance the excitement process of cerebral cortex and plays a role of refreshing.
Why green tea looks so green?
Green tea is non-fermented. It preserves the natural substances in the fresh tea leaves well, including more than 85% of tea polyphenols and caffeine and 50% of chlorophyll, and much vitamin. Thus green tea is featured with "pure soup, green leaves, strongly reserved taste". In addition, fixation is the key process affecting the quality of green tea. It destroys the activities of oxidation enzyme in fresh leaves at high temperature, inhibits the prooxidative of polyphenols enzymes so as to ensure "green tea leaves, green soup" after brewing.
Tea Set Suitable for Brewing the Green Tea
Green tea features clear water and green tea leaves. The tea set for brewing green tea should be full of changes.
Brewing of green tea should meet the requirements on color, aroma, appearance, and taste. For a high-quality green tea, a glass or a white porcelain tureen is a good brewing utensil. Use of glass is for enjoying the shape change of the green tea leaves, including its slow unfolding, sliding, and changing in the water. Glass is the best choice for needle-shaped tea and flat tea. Use of white porcelain tea set is for enjoying the color of the tea soup. The fine and smooth white porcelain can better set off the tender and bright greenness of the tea leaves and make the drinking process also pleasing to the eye and the mind. White porcelain tea set is the best choice for the rolled tender tippy teas such as Biluochun and Xinyang Maojian.