Study On Tea Polyphenols Industrial Wastes To Prepare The Production Materials Of Theanine

Preparing the production materials of L-theanine from tea polyphenol industrial waste liquid was studied from the perspective of flocculation impurify in this paper, the major contents studied are as follows:(1) Chromatographic conditions was ascertain to determine the content of theanine by high performance liquid chromatography(HPLC), then prepared the standard curve, L-theanine show a good linear relationship at range of 10μg/mL～160μg/mL, y=25506x, R2=0.9996. The average recovery of L-theanine was 96.71%, and the RSD was 0.35%(n=5). Through the flocculation of chitosan, the removal rates of protein and soluble sugar in waste liquid were both over 50%, and the removal rate of tea polyphenols was 46.54%, and the recovery rate of L-theanine was over 90%; Through polyamide absorption treatment, which was selected through the static adsorption experiment, the total removal rate of tea polyphenols was 82%in flocculation clear liquid, and the recovery rate of L-theanine was 90.4%in flocculation clear liquid; The cation ion-exchange resin, which was also selected through the static adsorption experiment, can adsorb amino acids specially, and adsorbed the treating liquid further, then eluted and dried, then the recovery rate of L-theanine was 79.55%and purity of the product was 52.08%.(2) Studied on the effect of the chitosan viscosity, temperature, pH, chitosan addition and flocculation time on the flocculation, and chose the OD650 value, the contents of tea polyphenols, protein, soluble sugar and theanine in clear liquid as the detection index. The single factor experiments obtained the chitosan flocculation optimum condition is:chitosan viscosity 300 cps, temperature 30℃, pH.3.0, chitosan addition 3.75 mg/mL, time 30 min.(3) Aimed at the promotion of the chitosan flocculation effect, a four-factor, three-level orthogonal experiment was designed according to the results of single factor tests, and chose the OD650 value, the contents of tea polypH.enols, protein, soluble sugar and theanine in clear liquid as the detection index. By comprehensive balance analyzing, got the best flocculation technological condition was A2 B1 C3 D2 that pH.3.0, temperature 25℃, chitosan addition 4 mg/mL and time 30 min, and adopted the condition, the effect of chitosan flocculation was better, and not only the removal rates of tea polyphenols, protein and soluble sugar were impoved, but also the recovery rate of L-theanine was rarely changed.(4) Preliminary research about the flocculation of carboxymethyl chitosan in waste showed, the effect of flocculation was little by direct adding carboxymethyl chitosan solid powder, however, the removal rates of tea polyphenols, protein and soluble sugar were quiet high by adding 1% carboxymethy chitosan solution(M/V), and the removal rate of L-theanine was higher at the same time.(5) Studied on the effect flocculation about the complex formulation of chitosan and xanthan gum in waste. After adding addition 4 mg/mL in waste, researched the effect of 1%xanthan gum solution addition, temperature, pH, chitosan addition and flocculation time on the flocculation, and chose the OD650 value, the contents of tea polyphenols, protein, soluble sugar and theanine in clear liquid as the detection index. The single factor experiments obtained the flocculation optimum condition is:1%xanthan gum solution 7 mL, temperature 30℃, pH.3.0, time 30 min.(6) Aimed at the promotion of the xanthan gum-chitoson flocculation effeet, a four-factor, three-level orthogonal experiment was designed according to the results of single factor tests, and chose the the OD650 value, the contents of tea polyphenols, protein, soluble sugar and theanine in clear liquid as the detection index. By comprehensive balance analyzing, got the best flocculation technological condition was A2 B1 C2 D3 that pH.3.0, temperature 25℃, chitosan addition 4 mg/mL+7 mL 1%xanthan gum solution, and time 40 min, and adopted the condition, the effect of flocculation was better, and the removal rates of tea polypH.enols, protein and soluble sugar were respectively impoved 11.13%,9.12%, and the removal rate of tea polypH.enols was also higher.