茶叶废弃物中茶多酚的提取+文献综述
关键词 茶多酚 水浸提 金属盐沉淀剂 萃取
毕业论文设计说明书（论文）外文摘要
Title Extracting Polyphenols from Tea Waste
Abstract
Single-factor control variable method was used to design the experiment in the paper. We investigated the following conditions of extracting polyphenols from tea waste: solid-liquid ratio, extraction temperature, extraction time, type and amount of salt used as precipitating agent, dosage of pH adjusting reagent in precipitation,the concentration and amount of acid which was used to dissolve the precipitated, extraction and drying process of polyphenols. The results showed that 1g tea waste with 20mL water was the best solid-liquid ratio. The conditions of the extraction temperature was 80 ℃. Extraction time was 20 min and pH was 7. ZnSO4 was used as precipitant.The deposit was dissolved by 4mol/L hydrochloric acid and then extracted by ethyl acetate. Finally, evaporating ethyl acetate in constant temperature bath at 70 ℃ and we got crude polyphenols. Polyphenols yield of the process was about 6%.
Keywords Polyphenols Water extraction Metal precipitant Extraction
目 次
1绪论 1
1.1茶多酚的介绍 1
1.2现阶段茶多酚提取的主流方法 1
1.3对于几种常见方法的总结及拟采用方法步骤 6
2实验部分 8
2.1材料及仪器 8
2.2实验方法 8
3结果分析与讨论 12
3.1标准曲线的测定 12
3.2浸提条件的研究 12
3.3金属盐沉淀剂的研究 15
3.4沉淀最佳pH的研究 16
3.5溶解沉淀物的酸的研究 17
3.6乙酸乙酯萃取茶多酚的工艺 19
3.7工艺流程中废水、废弃物的处置方法建议 19
结 论 21
致 谢 22
参考文献 23
1 绪论
1.1 茶多酚的介绍
茶多酚（Tea Polyphenols，TP）系从茶叶中提取，以儿茶素为主要成分多酚类化合物总称[1]，是一种目前尚不能人工合成的多功能、高效能天然抗氧化剂，安全无毒，具有抗癌、抗衰老、抗辐射、清除自由基、降血糖血脂等多种药理和保健功能，在食品、油脂、保健、医药、日化、精细化工等领域都有广泛应用[2]。
1.2 现阶段茶多酚提取的主流方法
1.2.1 溶剂萃取法
溶剂萃取法是利用茶叶中多酚物质和咖啡碱等有机物质在不同的溶剂中溶解度的差异进行分离，利用能与溶剂不互溶的茶多酚萃取剂将茶多酚萃取提纯。溶剂萃取法目前是国内外茶叶深加工企业采用最普遍的一种方法，其主要工艺流程见1.1[3]。
1—搅拌釜；2—过滤器；3—咖啡碱萃取塔；4—茶多酚萃取塔；5—咖啡碱精制罐；6—茶多酚精制罐