製程處理對不同品種茶樹製造紅茶化學成分與茶湯品質之影響

Changes in the Chemical Compositions and Sensory Quality Parameters of Black Tea Due to Variations of Processing Treatments

黃正宗(Cheng-Chung Huang)

指導教授 ： 柯淳涵

國立臺灣大學/生物資源暨農學院/森林學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.00152

摘要

不同品種茶樹加工製造紅茶時，不同製造方法與製程的控制，會造成茶葉化學成分的變化，進而影響紅茶的品質。本研究以行政院農委會茶業改良場魚池分場所選育之四種紅茶品系，進行條形紅茶製造。在製程中對揉捻及發酵二段製程進行「時程」控制，然後將紅茶進行化學成分分析及感官品評。藉此比較各品種（系）茶樹製造紅茶時品質的優劣，歸納出各品種（系）茶樹製造紅茶的最適加工控制條件，供日後商業生產之參考。
試驗結果顯示，在化學成分方面，總兒茶素、總多元酚類、總游離胺基酸、總可溶份等各處理間無顯著變化，但是總兒茶素、總多元酚類隨揉捻及發酵時間增加，有下降的趨勢。茶黃質總量則在春、夏茶時，各處理間達5％以上的顯著差異；當揉捻時間增加或發酵時間增加時，茶黃質總量提高，其中以TTES No. 18品種夏茶R120-F60處理最高，含量為11.98μmol/g，最低為B-69-80-21品系春茶R60-F90的處理，含量為5.99μmol/g；此外，揉捻時間增加同時也有助於紅茶水色成績提高，而茶黃質總量與總兒茶素亦呈負相關。
進行四品種（系）不同處理紅茶的感官品評，綜合分析春、夏茶滋味、香氣、水色等成績後，其製造紅茶品質優劣次序為TTES No. 18、B-69-80-21、B-56-70-66-1、B-56-70-211-1，其中，品種TTES No. 18，香氣滋味特殊，唯缺點水色橙黃；B-69-80-21、B-56-70-66-1二品系，互有優劣，品質相近，可拼堆改善品質。在茶黃質含量與感官品評成績相關性分析方面，發現春茶茶黃質與感官評鑑相關性相當高。其中TTES No. 18的茶黃質與「滋味」（r = 0.929）、「水色」（r = 0.900）達P≦0.05的相關性，「水色與滋味」達P≦0.01相關性，r值高達0.992。夏茶的茶黃質含量與茶湯「滋味」、「水色」或「水色與滋味」等則亦有相當程度的相關性。

關鍵字

化學成分 ； 茶黃質 ； 紅茶

並列摘要

For many strains of tea tree, manufacturing procedures and process control profoundly influence the chemical composition and sensory qualities of tea leaf. Full leaf black teas were produced from four strains of tea trees, selected by Yu-chih branch, Tea Research and Extension Station, COA. Sensory quality evaluation and tealeaf chemical composition analysis were conducted for temporal control of rolling and fermentation process. Qualities for different black tea of tea tree strains can be compared, and optimal schemes for tealeaf treatments were proposed for future commercial production.

From the chemical composition analysis of tea leaf, total catechins, total polyphenols, total free amino acids and total soluble contents were not significantly changed with respect to various treatments. However, total catechins and total polyphenols decreased with increasing duration of rolling and fermentation process. For spring and summer teas, total theaflavins differed significantly for more than 5% with respect to various processes. Total theaflavins increased with increasing duration of rolling and fermentation process. Among all strains tested, R120-F60 treatment of TTES No. 18 summer tea has highest total theaflavins of 11.98μmol/g. On the other hand, R60-F90 treatment of B-69-80-21 spring tea has lowest total theaflavins of 5.99μmol/g. In addition, increasing rolling time raised liquor colour score and related negatively to total catechins.

Sensory quality evaluation, including analyzing taste, flavour, liquor colour score for spring and summer teas, was conducted for four strains. Ranking of tea qualities from the best strain is: TTES No. 18, B-69-80-21, B-56-70-66-1 and B-56-70-211-1. Among strains tested, TTES No. 18 had a special flavour, but affected by orange liquor colour. Qualities of strains B-69-80-21 and B-56-70-66-1 were similar, with different pros and cons, and could be blended to amend each other. Spring tea was found to have significant correlation between sensory quality evaluation scores and total theaflavins. For TTES No. 18, significance of correlation between total theaflavins and taste (r = 0.929), liquor colour (r = 0.900) was P≦0.05; significance of correlation between total theaflavins and taste contenting liquor colour (r = 0.992) was P≦0.01. The above correlations for summer tea were also found significant.

並列關鍵字

Chemical composition ； Black tea ； Theaflavin

參考文獻

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