Waste Tea Comprehensive Utilization Of Industrial Production Technology Research

The producing and testing methods for industrial production of tea polyphenols, tea polysaccharide, theanine and caffeine by the utilization of waste tea dregs were studied intensively, which gained a good theoretical basis and experimental results in this work.1. The single factor and orthogonal tests results of polyphenols, tea polysaccharide, caffeine were showed that the optimum production conditions of extraction of tea polyphenols, tea polysaccharide, caffeine from tea powder in hot water reflux extraction process as the following:the ratio of solid to liquid was 1:16, thermal reflow temperature conditions was at 80℃, extraction time was 1.5h, and 3 times.2. The ultrasonic and heat reflux extraction method of tea polyphenols and caffeine was little difference, while heat reflux extraction method was better than ultrasonic extraction method for the extraction of tea polysaccharide. Therefore, the integrated extraction of three products should adopt the heat reflux extraction methods for the difference of tea polysaccharides extraction. Conversely, the ultrasonic extraction method was chosed if tea polysaccharide was not the key consideration for its advantages such as low temperature and saving time and reducing production costs.3. The screening experiment of macroporous resin was showed that the LX-X1 macroporous resin should be the ideal material for purification and enrich of tea polyphenols. Dynamic adsorption test results were as follows:when the concentration of the sample solution was 15.00 mg/ml, sample volume was 5BV, the sample flow rate was controlled in the 0.3-0.5BV/h and the ion-free flow rate was 0.5-0.8BV/h for washing to nearly colorless, then 6BV 75% ethanol elution for washing and flow rate was controlled at 0.5-0.8BV/h, the desorption was 93.15% and the purity was 90.05%. The purity of polyphenol content was increased more than 4 times compared with the before of purification, and caffeine was effectively removed.4. The effluent liquor and solution was evaporated to 1/5 by LX-X1 resin, then concentrated liquid was precipitated by alcohol, and the filtrate was concentrated to alcohol tasteless for the separation of non-alcoholic caffeine and theanine. The filtrating cake was gotten high purity tea polysaccharides by removing protein. The separation of theanine was chosed strongly acidic styrene cation exchange resin such as 001X7 and SLI010 resin, the adsorption of resin for its type exchange had a great influence on the experiment used LSI010 (H+) or 001x7 (H+) resin.5. The results of industrial amplification production for the comprehensive utilization of waste tea dregs were:the content of polyphenol was 90.12% and average yield was 16.85%, the content of tea polysaccharide was 30.12% and average yield was 3.95%, the content of theanine was50.08% and average yield was 1.56%. The highly content of polyphenols and tea polysaccharide and theanine could be obtained by further purification.6. The qualitative and quantitative test and analysis of tea polysaccharide and theanine and caffeine by thin-layer chromatography and spectrophotometry and PLC was explored respectively. The result was showed as the following:rapid detection of polyphenols and theanine and caffeine determined should choose thin layer chromatography in the production, tea polysaccharide content was determined by using phenol-sulfuric acid method but the content of tea polyphenols and caffeine, was determined by HPLC in the production.