Black tea

Black tea
Black tea

Black tea(simplified Chinese: 红茶; traditional Chinese: 紅茶; Japanese: 紅茶) is a type of tea that is more oxidized than the oolong, green, and white teas. All four types are made from leaves of the shrub (or small tree) Camellia sinensis. Black tea is generally stronger in flavor than the less oxidized teas. Two principal varieties of the species are used – the small-leaved Chinese variety plant (C. sinensis subsp. sinensis), used for most other types of teas, and the large-leaved Assamese plant (C. sinensis subsp. assamica), which was traditionally mainly used for black tea, although in recent years some green and white have been produced.
In Chinese languages and the languages of neighboring countries, black tea is known as “red tea” (紅茶, Mandarin Chinese hóngchá; Japanese kōcha; Korean hongcha), a description of the colour of the liquid; the term black tea refers to the colour of the oxidized leaves. In Chinese, “black tea” is a commonly used classification for post-fermented teas, such as Pu-erh tea; outside of China and its neighbouring countries, “red tea” more commonly refers to rooibos, a South African tisane.
While green tea usually loses its flavor within a year, black tea retains its flavour for several years. For this reason, it has long been an article of trade, and compressed bricks of black tea even served as a form of de facto currency in Mongolia, Tibet, and Siberia into the 19th century. Although green tea has recently seen a revival due to its purported health benefits, black tea still accounts for over ninety percent of all tea sold in the West.

Varieties
Generally, unblended black teas are named after the region in which they are produced. Often, different regions are known for producing teas with characteristic flavors.
• Ceylon tea
• Assam tea
• Bai Lin Gongfu tea
• Darjeeling tea
• Dianhong Gongfu tea
• Hu Hong Gongfu tea
• Eagle Red Gongfu tea
• Min Hong Gongfu tea
• Nilgiri tea
• Ningzhou Gongfu tea
• Keemun black tea
• Tan Yang Gongfu tea
• Yuehong Gongfu tea
• Yingde black tea
• Zhenghe Gongfu tea
• Lapsang Souchong black tea
• Jiuhong Gongfu tea
• Sun Moon Lake black tea
• Jin Jun Mei
• Fengpai black broken tea
• Jiuqu red plum tea
• Chuanhong Gongfu tea
• Yihong Gongfu tea
• Yangxian black tea
• Guihong Gongfu tea

Tea processing
• Withering萎凋:
water loss by respiration and evaporation and leaf becomes more pliable, dryness and heat aid in this process.
• Rolling揉捻:
breaking the leaf cell walls exposing sap to leaf substrate and air, and shaping.
• Fermentation發酵:
actually enzymic oxidation, noticeable change chemical composition and leaf becomes darker, moisture and heat aid in this process.
• Drying乾燥:
making the leaves ready for storage.

Health and nutrition
Plain black tea without sweeteners or additives contains negligible quantities of calories, protein, sodium, and fat. Some flavored tea with different herbs added may have less than 1 gram of carbohydrates. All teas from the camellia tea plant are rich in polyphenols, which are a type of antioxidant.
A 2001 Boston University study has concluded that short and long-term black tea consumption reverses endothelial vasomotor dysfunction in patients with coronary artery disease. This finding may partly explain the association between tea intake and decreased cardiovascular disease events.
In 2006, a German study concluded that the addition of milk prevents vascular protective effects of tea.
Theaflavin-3-gallate, a theaflavin derivative found in black tea, could reduce the incorporation of cholesterol into mixed micelles.