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Yunnan Pu'er tea is a very popular among the consumers of specialty teas. Because of its unique mode of production - Ottawa heap fermentation and aging process during storage, drying Maocha raw materials rich in polyphenols, sugars, proteins and other compounds in a variety of aerobic and anaerobic microorganisms and hydrothermal Under a series of transformation. Among them, the oxidation products of polyphenols The water-soluble dye based theabrowns (Theabrownine: TB) is the main component of tea soup, tea unique flavor of the formation of an important component, wherein the tea cakes cooked brunneissimus pigment content weight dry tea accounts for about 7% -15%. Theabrowns content level is an important indicator of the quality evaluation of tea. Study confirmed the formation mechanism theabrowns substance is: catechin oxidation products and polysaccharides, proteins, nucleic acids and other non-phenolic substances involved in the synthesis of non-dialysis polymers. Because of its composition is complex, far right tea in theabrowns in-depth research reports is almost empty, in order to explore the major phenolic Pu'er tea color effect pigments and storage time on the two kinds of tea processing technology pigment, this study from the tea brown pigment extraction, separation, color measurement, identification of substances characteristic start, first year with different traditions of Yunnan Pu'er tea processing technology (Cake) and modern pile-fermentation processing Pu'er tea (cooked cake) for the material analyzed in different years tea pigment content and moisture content, pH and shape as well as the relevance of the relationship between color and soup, and theabrowns test analyzes done some research, while the use of ultrafiltration Membrane filtration fraction change monitoring and preparation methods to extract theabrowns Pu'er tea on a combination of theabrowns conducted a series of preliminary studies, the findings as follows: ① different storage years on bread and cakes cooked green theaflavins (TF), thearubigins (TR), theabrowns (TB), and moisture content of the correlation analysis showed that: Green tea cakes and tea cakes cooked pigment changes with storage time to follow certain rules: With the extension of storage time , green tea cakes theaflavins, thearubigins, theabrowns and tea pigment volume has an increasing trend, and the higher the water content, the faster the change; while cooked tea cake of view, with the extension of storage time , and thearubigins theaflavins, tea pigment volume has decreased trend, while theabrowns is an increasing trend. With the prolongation of storage, the pH of green tea cake with a slight upward trend. ② from color (Hunter L ab) analysis, green tea cake tea cakes cooked brighter than cooked tea cake TB levels much higher than green tea cakes, but also with theabrowns content and brightness was negatively correlated, TB content the greater the darker the color, and the green tea cakes longer storage time, the appearance of dry tea, soup brightness decline. Cakes cooked tea color bias in red, blue color more oriented toward green tea cake, with the year increased storage, green cake, tea cakes cooked red value (Hunter a) and yellowness (Hunter b) there is a rising trend, and dry tea the appearance of redness also on the rise, but the yellowness no significant correlation. TR, TF on Hunter L ab values ??no significant correlation. This is the law of tea deeper degree of oxidation consistent. ③ In theabrowns system analysis test, it was found with leaching process unground tea samples measured theabrowns ground handling than the measured value is also high, indicating theabrowns tea extract suitable for use directly unground extraction, the extraction rate will be higher; tea with n-butanol extraction, the extraction time at 8 ℃ highest concentrations measured TB. ④ tea in the molecular weight theabrowns sizes, membrane interception right amount of tea in TB has an important impact on the retention, 100,000 units of membrane rejection allows TB retained 22.46%, 50,000 units of interception, you can only keep TB of 8.27%, and more for phenolic substances. ⑤ TB extraction and elution test results show that: with chloroform (trichloromethane) and ethyl acetate (Ethyl acetate) to remove TB in polyphenols, total nitrogen effect is not obvious, indicating polyphenols, total nitrogen is a major component of TB, and in bound form. ⑥ measured in this test Pu'er tea cakes like TB content 2.342mg/ml. Which also contains TP, AA, T-N, T-S, Caf,
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