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Tea is one of the three world famous beverage. With the development of the tea industry, tea processing more and more people pay attention to. Tea green pigment and low temperature extraction technology of tea, tea processing two main directions of research. The study of fresh tea leaves, crank up the leaf and dry tea as test materials, test materials suitable for tea green pigment extract and green tea extracts optimal parameters optimized by orthogonal experiment. Also made a more systematic study of tea low temperature extraction process parameters using quadratic general rotary trial design. Finally, the tea green pigment hyperchromic effect of low temperature extraction of tea. In this study, the main results are as follows: tea green pigment extraction materials selection and optimum extraction process parameters determined. The test results show that: the fixing leaf tea green pigment extraction test material. Order to crank up leaves as test materials, various factors that affect green tea extracts: ethanol concentration gt; alcohol tea than gt; time gt; temperature. The best tea green pigment extraction parameters: 100% ethanol, 4.5mL: 1g alcohol tea than the 75oC water extraction 25min, extracting the best results, the extraction rate of 31.50% than the previous literature reports 26.1 % 20.69% increase. Tea green pigment containing active ingredients rich in polyphenols, caffeine, amino acids, and is an excellent natural food coloring. Properties of tea green pigment. Tea green pigment at 430nm and 663nm at two characteristic absorption peaks. Tea green pigment is more stable to heat; unstable to visible light, visible light tea green pigment stability were particularly significant; tea green pigment at pH 5-6 the most stable; K , Na , Mg 2 , Ca 2 , Zn 2 , Cu 2 tea green pigment stability had little effect; Al 3 make tea green pigment to produce a small amount of yellow precipitate; Fe 2 , Fe 3 can immediately make tea green pigment produces dark brown precipitate. 3 tea low temperature extraction process parameters determine. The test results show that: the optimum conditions of low temperature extraction tea: temperature 58oC, time 38min, ratio of water to tea 11mL: 1g, cellulase, 0.17%, and the extraction of water pH 4.1 to 4.5, in this condition Baptist mentioning once extracted concentration, extraction yield to 25.20g / L, respectively, 12.83%. 4 tea green pigment hyperchromic effect of low temperature extraction tea. The test results show that: the amount of tea green pigment added, the pH value of the tea, as well as visible is the three main factors affecting tea liquor color. Tea pH 5.5, Tea chlorophyll conditions produces the best tea liquor color is added in an amount of 0.5mg / L, and the dark storage.
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