臺灣博碩士論文加值系統

隨著普洱茶保健功能的證實，近年來普洱茶在台灣及香港等地廣受歡迎，然而，台灣地區對普洱茶品質方面研究探討的並不多。本研究藉收集60個普洱茶樣，包含不同貯存年份之14個散茶、21個七子餅茶、12個磚茶、11個沱茶及2個六安茶，並以3個千兩茶及2個台灣產製的佛手黑茶作比較，探討不同貯存年份、製程及沖泡方法之普洱茶品質。
普洱茶水分含量絕大多數均高於10 %，而台灣產的黑茶水分含量則低於8 %；水活性在0.531 - 0.685，高於一般台灣茶；生菌數方面，有33個茶樣生菌數含量在105 cfu/g以上，而台製茶則僅在2 cfu/g以下；氟含量方面，除千兩茶在456 - 682 ppm為最高外，大部分茶樣氟含量在30 - 233 ppm間。普洱茶總兒茶素含量在0 - 5.7 %，比一般綠茶及烏龍茶少，而以生茶製程較高，且隨貯存年份之增加，有顯著減少之趨勢 (p<0.01)。
普洱生、熟茶類之特性方面，熟茶製程之普洱茶品質特點與貯存時間超過20年的普洱生茶相似。主成分分析結果可將普洱茶分成兩部分，貯存10年內的生茶為一部分，另一部分為熟茶及貯存超過10年的生茶。貯存20年以上之普洱生茶總兒茶素含量 (平均5.05 mg/g)與熟茶 (平均1.92 - 9.53 mg/g間)皆在10 mg/g以下。生茶茶樣貯存年份20年以上之茶樣水分含量 (10.35 %)，與熟茶樣水分含量 (10.50 - 11.77 %)皆超過10 %以上。
茶湯方面，利用煮茶法飲用普洱茶，茶湯中生菌數含量均低於沖泡法且在食品飲料類衛生標準 (每毫升中之生菌數限量有容器或包裝者應在200 cfu以下)之內。以一般標準沖泡法沖泡一次，茶湯氟含量最高的千兩茶 (2.38 mg/L)，可能有達人體每日攝取量的極限之顧慮。
體外試驗顯示普洱茶具有抗氧化的能力，貯存年份較久之普洱生茶在清除超氧陰離子能力方面高於其他茶樣，在清除自由基DPPH及總抗氧化能力方面則較貯存年份少之茶樣低。然而，無論生茶、熟茶或貯存年份之高低，普洱茶皆具有螯合金屬鐵離子之能力。
感官品評定量描述分析結果，普洱生茶香氣部分之甜香及青味較熟茶強。而貯存年份較久之普洱茶具特殊的香氣，如悶熱味及陳味較強。茶湯水色偏紅，滋味上之苦味、澀味及酸味均較弱，而餘後感部分之回甘感則較其他熟茶類或貯存年份少之生茶強。

As Pu’er tea’s health benefit is approved, Pu’er tea is getting poplular in Taiwan and Hong Kong nowadays. However, the quality of Pu’er tea available in Taiwan market has never been investigated. Totally 60 Pu’er tea samples including 14 San tea (散茶), 21 Chitse-Ping tea (七子餅), 12 Zhuan tea (磚茶), 11 Tou tea (六安茶) and 2 Liu-An tea (六安茶) with 1 to 50 year of storage were collected. Three Qian-Lian tea (千兩茶) and 2 made-in-Taiwan Budda-hand black tea (台灣佛手黑茶，MIT) were also examined for comparison. The objective of this study was to investigate the quality of Pu’er tea with different storage time, manufacturing and brewing methods.
The moisture content of most of Pu’er tea samples was higher than 10 % while that of the MIT tea samples was lower than 8 %. The water activity ranged from 0.531 to 0.685. Thirty-three out of 60 Pu’er tea samples had total bacteria counts (TBC) greater than 105 cfu/g while MIT tea samples had only less than 2 cfu/g. For fluoride, most of tea samples were in the range of 30 to 233 ppm while Qian -Lian tea had the content of fluoride as high as 456 to 682 ppm. Total catechins (TC) of Pu’er tea samples were in the range of 0 to 5.7 %, which was much lower than Green tea and Oolong tea samples. The non-post-fermented Pu’er tea had more TC than post-fermented Pu’er tea. The storage time was negatively correlated with polyphenolic compounds content significantly (p<0.01).
The properties of post-fermented Pu’er tea were no big difference with Pu’er tea with more than 20-year storage. The results of principal component analysis had the ability to discriminate the non-post-fermented Pu’er tea with less than 10-year storage time from Pu’er tea with more than 20-year storage time and post-fermented Pu’er tea. TC and the moisture content of Pu’er tea samples with more than 20-year storage time and post-fermented tea, which were both less than 10 mg/g and more than 10 %.
Comparing the TBC of several Pu’er tea samples by different brewing methods, the TBC only from boiling method was below the sanitation standard for beverages (200 cfu/ml). The fluoride content of tea infusion among selected nine tea samples, it was found that Qian-Lian tea had the highest content (2.38 mg/L) and it might exceed the maximun recommended daily allowance (4.0 mg/day for adults).
It was showed Pu’er tea with more than 20-year storage had stronger antioxidant ability for scavenging super-oxide anion, but weaker on scavenging DPPH radical and trolox equivalent antioxidant activity. All selected Pu’er tea samples had strong antioxidant ability with chelating ferrous ions.
For Quantitative Descriptive Analysis (QDA), non-post-fermented Pu’er tea was more mellow and grassy than post-fermented tea samples. Non-post fermented Pu’er tea with long-time storage was more stewed and stale. Its tea infusion was redder and less bitter, astringency and sour. But it was stronger in brothy than post-fermented tea and Pu’er tea with short-time storage.

中文摘要 1
英文摘要 3
壹、 前言 5
貳、 文獻整理7
一、 中國飲茶文化的發展7
二、 我國茶葉茶葉種類及其製茶過程的簡介8
三、 普洱茶簡介8
(一) 普洱茶史8
(二) 普洱茶的製作及其特性9
(三) 普洱茶在台灣的發展情形10
四、 千兩茶及台灣佛手黑茶簡介12
(一) 千兩茶12
(二) 台灣佛手黑茶13
五、 茶葉中的化學組成及其抗氧化之特性13
六、 自由基的形成及其抗氧化物的作用與種類15
(一) 自由基15
(二) 抗氧化物的作用與種類17
七、 感官品評之描述分析18
參、 材料與方法22
一、 試驗材料22
二、 試驗設計與流程22
三、 試藥 31
四、 試驗方法31
(一) 茶樣之處理31
(二) 茶葉分析32
(三) 茶湯分析35
(四) 抗氧化之測定36
(五) 感官品評分析38
(六) 統計分析38
肆、 結果與討論39
一、 普洱茶、千兩茶及台灣佛手黑茶茶葉品質分析39
(一) 水分、水活性及微生物39
(二) 氟含量41
(三) 兒茶素及咖啡因47
(四) 總酚及其相對聚合度51
(五) 不同種類普洱生茶及熟茶物化品質特性59
(六) 普洱生茶及熟茶物化品質與貯存年份的關係59
(七) 普洱茶各物化品質與貯存年份間之相關性66
(八) 不同貯存年份與製程之茶樣品質間主成分分析66
(九) 部分普洱茶之茶黃質、茶紅質及茶褐素分析69
二、 普洱茶茶湯之品質分析73
(一) 不同沖泡及煮茶法普洱茶湯pH值、可溶分及總酚含量73
(二) 利用小壺泡、一般標準沖泡及煮茶方式探討生菌數變化情形74
(三) 利用小壺泡、一般標準沖泡及煮茶方式探討氟含量之差異80
三、 普洱茶湯抗氧化能力評估 83
(一) 不同沖泡及煮茶方式普洱茶湯清除超氧陰離子能力83
(二) 普洱茶湯清除超氧陰離子及螯合鐵能力84
(三) 普洱茶湯清除DPPH能力86
(四) 普洱茶湯總抗氧化能力92
四、 普洱茶及台灣佛手黑茶感官品質之探討96
(一) 感官品評數據可信度之探討96
(二) 普洱茶及台灣佛手黑茶之定量描述分析99
(三) 定量描述分析各描述語之相關性105
伍、 結論 107
陸、 參考文獻109
附錄一119

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