臺灣博碩士論文加值系統

本研究以高效能液相層析法定量分析不同季節採摘的茶菁﹙台茶12號）於文山(條型)包種茶製程中兒茶素（catechins）、黃酮醇 (flavonols)、酚酸 (phenolic acids)、茶黃質(theaflavins, TFs)等多元酚類及植物鹼(alkaloids)含量之變化。結果發現，各種多元酚類化物及植物鹼之含量於製程中有不同的變化情形。
兒茶素包括(-)-epicatechin﹙EC﹚、(-)-epigallocatechin (EGC)、(-)-epicatechin gallate (ECG)、(-)-epigallocatechin gallate (EGCG)及(+)-gallocatechin gallate (GCG)，各存在量分別為1.91-7.30mg/g (乾葉重)、 16.01-53.51mg/g、12.32-31.32mg/g、46.56-106.1mg/g及10.20-74.28mg/g。不同季節茶菁之 EC、EGC、ECG、EGCG 及 GCG 在包種茶製造時之變化趨勢略同，但變化程度有所差異，以冬茶GCG含量變化最明顯。日光萎凋後兒茶素平均增加 7%，室內萎凋期間則減少7%，炒菁後兒茶素含量大幅增加，除春茶外，夏茶、秋茶和冬茶之兒茶素含量皆增加約 30%。
茶菁中的黃酮醇有 myricetin 及 quercetin，以醣的形式存在，經酸水解成其配醣基﹙aglycone﹚後進行定量分析，各種的存在量分別為 2.32-3.88 mg/g 及1.45-2.22 mg/g，於製程中黃酮醇之變化不大，且無規則性。
茶黃質為多元酚類之氧化產物，茶菁中其含量極微，在 0.5 mg/g 以下。日光萎凋時就存在，在室內萎凋時漸增，於第二次攪拌後漸減，第三次攪拌後又再度增加，炒菁後則有明顯減少現象（除 TF4）損失率達50%以上。
酚酸包括 gallic acid 與 theogallin，二成分於製成中變化情形不同，前者於茶菁製成包種茶後含量平均減少 81%，而後者於製程中則無顯著變化。
咖啡因（caffeine）與可可鹼(theobromine)為茶葉中的植物鹼，此些化學成分於製茶過程中之變化不大，屬穩定性的成分。茶菁中咖啡因存在量為17.59-27.95mg/g；可可鹼為0.16-0.93m

The contents of catechins, flavonols, phenolic acids, theaflavins and alkaloids during the processing of pouchong tea (Taiwan Tea No. 12) were determined by HPLC. It was found that each stage of pouchong tea processing would affect the amounts of polyphenols and alkaloids.
Tea catechins are composed of (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECG), (-)-epigallocatechin gallate (EGCG) and (-)-gallocatechin gallate (GCG). They were present at 1.91-7.30mg/g (dried leaves), 16.01-53.51mg/g, 12.32-31.32mg/g, 46.56-106.10mg/g and 10.20-74.28mg/g, respectively. The trends of catechins of changes during pouchong tea processing were similar for the tea leaves picked at different seasons. However, the extents of the changes were different, especially GCG in winter tea. On the average, catechins increased 7% after solar withering and decreased 7% after indoor withering. Catechins increased about 30% after fixing except spring tea.
Flavonols in teas are myricetin and quercetin, existed as their glycosides. Quantitative analysis of tea flavonols was performed by analyzing their aglycones after acid hydrolysis. Myricetin and quercetin were found to be 2.32-3.88mg/g and 1.45-2.22mg/g respectively. Two flavonols did not show significant changes during processing of pouchong tea.
Phenolic acids are mainly consisted of gallic acid and theogallin. After fixing, the amount of gallic acid reduced 81% on an average. But the change in theogallin was insignificant during tea processing.
Theaflavins (TFs) are the well-defined group of flavonoid oxidative products. They existed in trace amount in tea leaves, usually less than 0.5mg/g. Theaflavins were found in fresh tea leaves before solar withering, then gradually increased during indoor withering. They were gradually reduced after the 2nd rotating and increased again after the 3rd rotating. After fixing, TFs reduced significantly (except TF4), and the loss exceeded 50%.
Caffeine and theobromine are the alkaloids in tea. Variations in alkaloids contents in tea leaves during pouchong tea processing were insignificant. The amounts of caffeine and theobramine in tea leaves were found to be 17.59-27.95mg/g and 0.16-0.93mg/g

目 錄
中文摘要
英文摘要 頁次
壹、 前言 1
貳、 文獻整 2
一、 台灣茶葉簡介 2
（一） 茶樹品種 2
（二） 台灣茶業 2
（三） 特色茶 3
二、 文山包種茶 6
三、 茶葉之化學組成 7
（一） 黃烷醇 10
（二） 黃酮醇及其配醣體 12
（三） Flavones 12
（四） 酚酸及縮酚酸 14
（五） 酚類氧化物 14
四、 茶葉製程之生物化反應 14
（一） 製造時生化反應 14
（二） 茶葉酚類化合物之變化 19
五、 茶葉化學組成分的重要性 24
（一） 成茶感官品質方面 24
（二） 食品機能性方面 25
六、 茶葉主要化學成分的分析方法 29
參、 材料與方法 31
一、 試驗材料 31
（一） 試驗茶菁樣品 31
（二） 試藥與試劑 31
（三） 儀器設備 33
二、 試驗流程 35
（一） 採樣次序 35
（二） 成分分 37
三、 試驗方法 38
（一） 樣品前處理 38
（二） 樣品之萃取 38
（三） 總酚類含量之測定 39
（四） 茶葉萃取液之高效能液相層析 39
（五） 茶黃質標準品之製備 41
（六） 茶黃酮醇醣類LC-MS 分析 43
（七） 水分含量之測定 43
（八） 統計分析 44
肆、 結果與討論 45
一、 包種茶中多元酚類及植物鹼分析方法之建立 45
（一） 兒茶素、沒食子酸與植物鹼 45
1. 水萃取條件之探討 45
2. 高效能液相層析 47
3. 質譜分析 49
（二） 茶黃酮醣類 49
1.LC-MS分析 49
2.酸水解試驗 53
3.酸水解產物（黃酮醇）高效能液相層析 56
（三） 茶黃質 56
1. 層析前處理 56
2. 高效能液相層析 60
二、 包種茶製程中總酚含量之變化 60
三、 包種茶製程中各多元酚類與植物鹼含量之變化 65
（一） 兒茶素（catechins） 65
（二） 酚酸（phenolic acids） 73
（三） 黃酮醇(flavonols) 76
（四） 茶黃質(theaflavins) 76
（五） 咖啡因(caffeine)與可可鹼(theobromine)80
四、 不同季節茶葉各多元酚類含量之差異性 83
五、 包種茶茶菁與成茶主要成分含量之比 85
伍、結論 87
陸、參考文獻 89
柒、附錄 98

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