福建农业学报
福建農業學報
복건농업학보
Fujian Journal of Agricultural Sciences
2015年
9期
856-862
,共7页
王丽丽%宋振硕%陈键%杨军国%张应根%陈林
王麗麗%宋振碩%陳鍵%楊軍國%張應根%陳林
왕려려%송진석%진건%양군국%장응근%진림
茶叶%鲜叶%萎凋%儿茶素%生物碱%动态变化
茶葉%鮮葉%萎凋%兒茶素%生物堿%動態變化
다협%선협%위조%인다소%생물감%동태변화
tea%fresh leaves%withering%catechins%alkaloids%change
以肉桂、水仙等10个茶树品种春季新梢(采摘嫩度为1芽2、3叶和中小开面2~4叶)为供试材料,在控温控湿(22~22℃、RH 35%~45%)条件下萎凋,于鲜叶萎凋失水减重率为0、15%、30%、45%、60%时取样,检测其儿茶素和生物碱含量的变化。结果表明,在萎凋失水率为30%~45%范围内,供试茶样中儿茶素组分含量及总量具有最大值,说明萎凋前期促进儿茶素的转化形成;随着萎凋失水程度加重,儿茶素组分EGCG、EC 和 ECG 含量及其总量呈现先增后减、总体减少趋势,EGC 和 TB 含量以逐步减少为主,而 CAF 含量和生物碱总量则表现为逐渐增加趋势,而且1芽2、3叶各组分变化幅度大于中小开面2~4叶;主成分分析和聚类分析均可获得较为一致的结果,即110份供试茶样均可按芽叶嫩度分成1芽2、3叶型和中小开面2~4叶型2种类型,基于萎凋工序分类的主成分分析显示供试茶样的儿茶素和生物碱在萎凋期间含量呈现递变性增减趋势,表明萎凋过程是儿茶素类物质在多酚氧化酶作用下长时间缓慢氧化和降解的过程。因此萎凋工序对儿茶素和生物碱含量有一定影响,可通过调节鲜叶萎凋失水程度来调控二者的含量及组成比例,从而为茶叶风味品质调整及其活性成分的开发利用提供依据。
以肉桂、水仙等10箇茶樹品種春季新梢(採摘嫩度為1芽2、3葉和中小開麵2~4葉)為供試材料,在控溫控濕(22~22℃、RH 35%~45%)條件下萎凋,于鮮葉萎凋失水減重率為0、15%、30%、45%、60%時取樣,檢測其兒茶素和生物堿含量的變化。結果錶明,在萎凋失水率為30%~45%範圍內,供試茶樣中兒茶素組分含量及總量具有最大值,說明萎凋前期促進兒茶素的轉化形成;隨著萎凋失水程度加重,兒茶素組分EGCG、EC 和 ECG 含量及其總量呈現先增後減、總體減少趨勢,EGC 和 TB 含量以逐步減少為主,而 CAF 含量和生物堿總量則錶現為逐漸增加趨勢,而且1芽2、3葉各組分變化幅度大于中小開麵2~4葉;主成分分析和聚類分析均可穫得較為一緻的結果,即110份供試茶樣均可按芽葉嫩度分成1芽2、3葉型和中小開麵2~4葉型2種類型,基于萎凋工序分類的主成分分析顯示供試茶樣的兒茶素和生物堿在萎凋期間含量呈現遞變性增減趨勢,錶明萎凋過程是兒茶素類物質在多酚氧化酶作用下長時間緩慢氧化和降解的過程。因此萎凋工序對兒茶素和生物堿含量有一定影響,可通過調節鮮葉萎凋失水程度來調控二者的含量及組成比例,從而為茶葉風味品質調整及其活性成分的開髮利用提供依據。
이육계、수선등10개다수품충춘계신소(채적눈도위1아2、3협화중소개면2~4협)위공시재료,재공온공습(22~22℃、RH 35%~45%)조건하위조,우선협위조실수감중솔위0、15%、30%、45%、60%시취양,검측기인다소화생물감함량적변화。결과표명,재위조실수솔위30%~45%범위내,공시다양중인다소조분함량급총량구유최대치,설명위조전기촉진인다소적전화형성;수착위조실수정도가중,인다소조분EGCG、EC 화 ECG 함량급기총량정현선증후감、총체감소추세,EGC 화 TB 함량이축보감소위주,이 CAF 함량화생물감총량칙표현위축점증가추세,이차1아2、3협각조분변화폭도대우중소개면2~4협;주성분분석화취류분석균가획득교위일치적결과,즉110빈공시다양균가안아협눈도분성1아2、3협형화중소개면2~4협형2충류형,기우위조공서분류적주성분분석현시공시다양적인다소화생물감재위조기간함량정현체변성증감추세,표명위조과정시인다소류물질재다분양화매작용하장시간완만양화화강해적과정。인차위조공서대인다소화생물감함량유일정영향,가통과조절선협위조실수정도래조공이자적함량급조성비례,종이위다협풍미품질조정급기활성성분적개발이용제공의거。
Under controlled indoor conditions at 20-22℃and 35%-45% RH,withering of the spring tea shoots,i. e.,2 or 3 leaves with a bud (A)and 2 to 4 leaves with a banjhi bud (B),harvested from 10 tea cultivars,including Rougui and Shuixian,was conducted to study the compositional changes in the leaves.Samples were collected at water loss of the leaves at 0,15%,30%,45% and 60% to determine the catechin and alkaloid contents using HPLC.The results showed that the highest contents of catechin monomers and total catechins occurred when water loss of the leaves was in the range of 30% to 45%,indicating transformation of catechinsduring early stage of withering.As the withering progressed,EGCG,EC,ECG and total catechins of the samples began to fall,and EGC and TB reduced gradually,while CAF and alkaloids increased.The scope of the changes were more prominent in Group A than B. The principal component analysis (PCA ) and the cluster analysis rendered a similar classification in dividing the 110 samples into the two types,A and B,which were grouped based on the tenderness of the tea shoots.The PCA results suggested that tea catechins and alkaloids rose and fell due to the oxidization and degradation of catechins by the polyphenol oxidase during the time period.Apparently,withering affected the contents of catechins and alkaloids in the leaves.Therefore,it was conceivable that proper control on moisture loss of the leaves could improve the flavoring and active components of the resultant tea.