【作者】 常亚丽；

【导师】 曾亮；

【作者基本信息】 西南大学 ， 茶学， 2012， 硕士

【摘要】 本文从絮凝除杂的角度,对从茶多酚工业废液制备用于生产茶氨酸的原料进行了研究,主要研究内容如下：(1)确定高效液相色谱法测定茶氨酸的色谱条件,制作标准曲线,得方程y=25506x,相关系数0.9996,茶氨酸在10μg/mL～160 pg/mL浓度范围内与峰面积线性关系良好,茶氨酸回收率96.71%,RSD 0.35%(n=5)；废液经壳聚糖在絮凝,蛋白质和可溶性多糖去除率均大于50%,荼多酚去除率46.54%,茶氨酸回收率超过90%；经静态吸附实验选择PA树脂做进一步吸附处理,茶多酚去除率82%,茶氨酸保留率90.4%；经静态吸附实验选择转H+型732强酸型阳离子交换树脂进一步交换吸附茶氨酸,洗脱干燥后得纯度52.08%的茶氨酸,提取率为79.55%。(2)考察壳聚糖粘度、温度、样液pH.、壳聚糖添加量及时间对絮凝效果的影响。以絮凝清液在波长650 nm下吸光度,茶多酚、蛋白质、可溶性多糖及茶氨酸的含量为指标,确定了壳聚糖粘度为300 cps,温度为30℃、壳聚糖添加量为3.75mg/mL,时间为30 min时其絮凝效果较好。(3)在单因素试验的基础上,为进一步优化壳聚糖絮凝工艺,选定pH.、温度、壳聚糖添加量及时间做四因素三水平的正交实验,并以絮凝清液在650 nm下吸光度、清液中茶多酚、蛋白质、可溶性多糖及茶氨酸的含量为指标,用综合平衡法最终却定了絮凝最优工艺为pH.为3.0,温度为25℃,壳聚糖添加量为4 mg/mL,时间30 min,后经试验结果验证,茶多酚及蛋白质的去除率进一步提高,可溶性多糖及茶氨酸的保留率几乎不变。(4)初步研究了水溶性羧甲基壳聚糖对溶液的絮凝效果,经试验表明直接加入羧甲基壳聚糖固体几乎无絮凝效果,而1%羧甲基壳聚糖对溶液中的茶多酚、蛋白质及可溶性多糖的去除效果都非常显著,但是对茶氨酸的去除率也较高。(5)研究黄原胶与壳聚糖复配使用对料液的絮凝效果。在确定料液中加入壳聚糖的4 mg/mL后,依次考查1%黄原胶添加量、温度、pH.及时间对絮凝效果的影响,并综合考察絮凝清液在650 nm下的吸光度、清液中茶多酚、蛋白质、可溶性多糖及茶氨酸的含量为指标,确定了单因素条件下的最佳絮凝效果条件,即1%黄原胶添加量为7 mL,温度30℃,pH.3.0,时间30min。(6)在单因素实验的基础上,选定pH.、温度、1%黄原胶溶液添加量及时间做四因素三水平的正交实验,并以絮凝清液在650 nm下的吸光度、清液中茶多酚、蛋白质、可溶性多糖及茶氨酸的含量为考察指标,用综合平衡法确定了絮凝最优工艺,即为pH.为3.0,温度为25℃,4 mg/mL壳聚糖+7 mL 1%黄原胶溶液,时间40 min,相较于单独使用壳聚糖进行条件优化后的絮凝试验,蛋白质及可溶性多糖的去除率显著提高,依次提高了11.13%、9.12%,茶多酚的去除率也有一定提高.更多还原

【Abstract】 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.更多还原