Liu Bao tea (六堡茶) is a classic example of Chinese black tea, or heicha (黑茶). (In Chinese, "black" tea refers to a category of dark, fermented teas similar to puerh, and distinct from red tea. What is usually called "black" tea in English is actually red tea.) It's named after the place where it was traditionally produced, Liu Bao, or "Six Castles," Village in Cangwu. During the planned economy period, the definition of Liu Bao tea widened to include any black tea produced using the traditional Wuzhou method in the surrounding areas of Guangxi, including Heng County, Lin'gui County, and cities such as Guilin, Hezhou, and Cenxi. Production was concentrated around three major factories in Wuzhou, Guilin, and Heng County. Altogether, the Wuzhou area produces a little over 1200 tons of Liu Bao tea each year. Of these, over 800 tons are exported annually to nearby regions and countries such as Hong Kong, Macau, Southeast Asia, and Japan. The remainder is sold domestically, with the major markets located in the provinces of Guangdong and Guangxi.
For many years, there was no unified standard for the export of Liu Bao tea. Trade agreements relied largely on the mutual approval of the two parties regarding the standard of the tea, rather than any accurate or scientific criteria. There wasn't any kind of governing body or officially recognized standard to regulate manufacturing, which made it difficult to expand the Liu Bao market. So it became necessary to establish a unified standard in order to promote a flourishing export market, regulate the examination and quality control of Liu Bao, and protect the legal rights of all parties involved in the export industry.
The Guangxi Inspection and Quarantine Bureau released the official export standard for Liu Bao tea on April 8, 2003, and implemented it on October 8 of the same year. It was the first industry standard for Liu Bao tea and had the support of fifteen relevant companies and organizations, including the Technical Supervision Department, the Guangxi Tea Import and Export Corporation, the Guangxi Local Products Corporation, and the two major enterprises who had been steadily producing Liu Bao tea at the time. The official Liu Bao Tea standard contains a precise definition: Liu Bao tea (traditionally also called Liu Pao in English) is made from the leaves of the Camellia sinensis (L.) O. Kuntze tea plant. It's made using the tender leaves and stems of new shoots and is manufactured according to the traditional Liu Bao tea-making method. This is divided into two parts: the first is the early processing, which includes "kill-green" (firing in a wok to halt oxidization), rolling, heaping, or wodui (渥堆), rolling again, then drying. The second part of the process is refining the tea, which involves sifting, blowing, selecting, grading, initial steaming while heaped, a second steaming whilst pressing into shape, and finally, maturing. This delicate and complex process results in the unique black tea that is Liu Bao.
Although the official Liu Bao Tea standard doesn't go into the manufacturing process in much detail, a more in-depth introduction to the various steps in the process can be found in related publications such as the Guangxi Local Products Corporation's The Processing and Inspection of Tea Leaves, which includes a thorough introduction.
In addition, two researchers from the Wuzhou Tea Factory in Guangxi - technician Yang Jinquan ( 楊錦泉) and former factory deputy head Liao Qingmei (廖慶梅) - have carried out in-depth quantitative studies into each step in the Liu Bao tea production process, based on practical experimentation. This has allowed them to make some recommendations as to how best to control and evaluate the production process; their findings represent the most complete, scientific, and practical research to date on the traditional Liu Bao tea production method.
Liu Bao tea is known for its distinctive aroma, reminiscent of the betel, or areca, nut. The official Liu Bao Tea standard contains the following description of this famed Liu Bao fragrance: "Liu Bao maocha (毛茶, unprocessed tea leaves) should possess these qualities: the fragrance should be mellow, rich, and refreshing; the flavor rich, strong and refreshing. Refined, fully processed Liu Bao tea should have the following qualities: the fragrance should be pure, mellow, and rich, with the scent of betel nut; the taste should be strong and full-bodied with a betel nut flavor and a sweet aftertaste." (There will be a more detailed discussion of this distinctive fragrance in the Further Readings on our blog.)
In addition to the requirements for fragrance and flavor, the Liu Bao Tea standard also outlines the following qualities: Liu Bao maocha liquor should be a clear reddish-yellow; the brewed leaves should be tender with an even yellow-brown color. The unbrewed leaves are straight, even, tightly twisted and of uniform size. They are light brown and lustrous in appearance, and are categorized as "clean," meaning that no extraneous matter (such as tea twigs or other ingredients) are present in the tea leaves. Refined Liu Bao tea should have clear, deep red liquor, and the brewed tea leaves should be reddish-brown. Before brewing the leaves are straight and even like the maocha, but with a dark, blackish-brown glossy appearance, and are also "clean." In addition to this, the Liu Bao tea produced in Wuzhou is aged in caves for a long time, and develops a mottled yellow color known as "Golden Flowers," or Jin Hua (金花).
The "Golden Flowers" that develop on Liu Bao tea leaves become more prominent with maturation - experts have identified them as Eurotium cristatum, a type of beneficial fungus. As the Eurotium cristatum grows, it metabolizes certain chemicals from the tea leaves and produces various extracellular enzymes including polyphenol oxidase, pectase, cellulase, and proteases. The chemical changes catalyzed in the tea include oxidization, polymerization, degradation, and isomerization; for example, the starch in the tea leaves is transformed into monosaccharides, and polyphenol-type chemical compounds are oxidized. These chemical transformations alter the color, scent, and flavor of the tea. The color of the tea liquor becomes a reddish-brown, the "raw" scent is eliminated, and the aroma and flavor are enhanced; all of these elements come together to create Liu Bao tea's distinctive style and flavor. Over the long history of Liu Bao tea drinking, the presence of "Golden Flowers" has become a well-established marker of superior quality tea.
Liu Bao tea is often summarized using four words: "red, rich, aged, and mellow." The best Liu Bao teas are recognized by their distinct betel nut taste and aroma, and the presence of "Golden Flowers" on the tea leaves.
In 2002, prior to the release of the Liu Bao Tea standard, there were only two factories producing Liu Bao - the Wuzhou Tea Factory and the Wuzhou Tea Import and Export Corporation Tea Processing Plant. The tea they produced was mostly for export. With the support and cooperation of these two enterprises, the Guangxi Inspection and Quarantine Bureau compiled the Liu Bao Tea standard based on the existing practices of the two factories, and released it the following year (2003). This standard outlined the technical specifications for the production of Liu Bao tea, and marked the start of an era of standardized production. It represented a milestone in the development of Liu Bao tea, signifying that the art of Liu Bao production had reached a mature and stable state, and that Liu Bao tea had become a product with a rich sense of terroir. These two factories have now been manufacturing and exporting Liu Bao tea for several decades; they have been instrumental in developing and passing down the history, craft, and culture behind Liu Bao tea.
This new era of standardized production brought about a significant increase in the quality of Liu Bao tea and guaranteed a uniformly high standard, which earned it the recognition of both local and international consumers. This helped the industry to gradually emerge from a difficult period and really begin to flourish. The implementation of the official Liu Bao Tea standard has had tangible benefits for all involved in the industry, including tea factory owners, tea merchants, supervisory bodies, and, of course, tea drinkers.