成茶白毫的多少及隐显是评定茶叶品质优劣的重要标志之一。为了明确茶毫中的化学组成,以富含茶毫的碧螺春、滇红、白毫银针及白牡丹4个茶样为研究对象,将茶毫与茶身进行分离,利用碳氮元素分析仪对其总碳、总氮及碳氮比进行分析,氨基酸自动分析仪分析其氨基酸组分,电感耦合等离子体发射光谱（ICP-OES）用来测定其主要矿质元素含量。茶毫中的C、N含量分别为2.96%~4.74%和42.87%~45.58%,其中N含量显著低于茶身（P<0.01）,C含量差异不显著,C/N茶毫显著高于茶身;茶毫中水解氨基酸、游离氨基酸含量分别为10.78%~12.46%和20.78~34.65βmg·g-1,其中水解氨基酸主要组分及总量均显著低于茶身（P<0.01）,游离氨基酸总量低于茶身（P<0.05）,而茶氨酸、天冬酰胺、甘氨酸、γ-氨基丁酸等游离氨基酸组分差异不显著,茶毫中茶氨酸所占游离氨基酸的比例显著高于茶身（P<0.05）;茶毫中的矿质元素普遍低于茶身,其中P、S含量极显著低于茶身（P<0.01）,其他元素差异不显著。由此可见,茶毫中的氨基酸和矿质元素含量并不比茶身高,但品质成分组成比例的差异赋予了富含茶毫茶叶特有的品质特征。
Abstract
The amount and density of tea hairs on made tea is an important indication to assess tea quality. To determine the chemical compositions of tea hairs, four tea samples rich in tea hairs, namely, Biluochun, Yunnan black tea, Baihao Yinzhen and Baimudan were used. Tea hairs was compared to the non-pubescent leaves. The contents of C, N and C/N, the composition and contents of amino acids, primary mineral elements were analyzed by elemental analyzer, automatic amino acid analyzer and ICP-OES respectively. The C and N contents in tea hairs ranged from 2.96% to 4.74% and 42.87% to 45.58%, respectively. The N contents in tea hairs were significantly lower than those in the non-pubescent leaf (P<0.01), while C/N showed an opposite trend and C contents showed no significant difference. Hydrolytic amino acids and free amino acid contents in tea hairs ranged from 10.78 % to 12.46% and 20.78βmg·g-1 to 34.65βmg·g-1, respectively. The major constituents and the total amount of hydrolytic amino acids and free amino acids in tea hairs were all significantly lower than those in tea body (P<0.05), with an exception of the ratio of theanine to total free amino acids (P<0.05). While the differences of the free amino acid constituents (theanine, asparagine, glycine, and γ-GABA) were not significant. The mineral elements in hairs were generally slightly lower than those in tea. Among them, the P and S contents showed the largest differences (P<0.01). In summary, the contents of amino acids and mineral elements in tea hairs are not higher than those in tea body, but the composition differences in quality constituents might contribute to the special quality characteristics.
关键词
C/N /
氨基酸 /
茶毫 /
矿质元素
Key words
amino acid /
C/N /
mineral element /
tea hairs
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 周巨根, 刘祖生. 茶树芽叶茸毛的研究——Ⅲ.茸毛性状的遗传与变异[J]. 茶叶, 1990(4): 7-10.
[2] 周巨根, 刘祖生. 茶树芽叶茸毛的研究——Ⅲ.茸毛性状的遗传与变异(续)[J]. 茶叶, 1991(1): 19-21.
[3] 肖扬书, 王镇恒. 茶叶茸毛形态结构及形态发生的研究[J]. 茶业通报, 1990(4): 9-10.
[4] 肖扬书, 王镇恒. 茶叶茸毛与品质关系的研究[J]. 安徽农学院学报, 1991(1): 39-44.
[5] 高香凤, 李慧玲, 王庆森. 茶树叶片组织结构及次生物质与抗虫性关系研究进展[J]. 茶叶科学技术, 2011(2): 7-11.
[6] 郑高云. 不同茶树品种对茶尺蠖抗性机制的研究[D]. 合肥: 安徽农业大学, 2008.
[7] 王庆森, 黄建, 陈常颂, 等. 茶树种质叶片组织结构与其对黑刺粉虱抗虫性的关系[J]. 茶叶科学, 2009, 29(1): 60-66.
[8] 金珊. 不同茶树品种抗假眼小绿叶蝉机理研究[D]. 杨凌: 西北农林科技大学, 2012.
[9] Hazarika L K, Bhuyan M, Hazarika B N.Insect pests of tea and their management[J]. Entomology, 2009, 54(54): 267-284.
[10] 陈义, 孔维婷, 孙慕芳, 等. 信阳毛尖茶白毫与品质关系的研究[J]. 食品科技, 2010(7): 124-126.
[11] 邵元海, 周静峰, 徐德良, 等. 无锡毫茶白毫与品质关系的研究[J]. 茶叶, 2010(2): 93-95.
[12] 叶乃兴, 刘金英,郑德勇, 等. 白茶品种茸毛的生化特性[J]. 福建农林大学学报(自然科学版), 2010, 39(4): 356-360.
[13] 郭桂义, 孙慕芳, 陈义, 等. 茶叶茸毛的化学成分测定[J]. 食品科学, 2011(8): 244-247.
[14] Shen F M, Chen H W.Element composition of tea leaves and tea infusions and its impact on health[J]. Bulletin of Environmental Contamination and Toxicology, 2008, 80(3): 300-304.
[15] 赵颖, 张利. 蒙山茶叶中矿质元素含量的季节特征及溶出率研究[J]. 茶叶科学, 2011, 31(6): 479-484.
[16] Ye X, Jin S, Wang D, et al.Identification of the origin of white tea based on mineral element content[J]. Food Analytical Methods, 2017, 10(1): 1-9.
[17] Nkansah M A, Opoku F, Ackumey A A.Risk assessment of mineral and heavy metal content of selected tea products from the Ghanaian market[J]. Environmental Monitoring & Assessment, 2016, 188(6): 1-11.
[18] 王齐, 朱伟伟, 苏丹, 等. 蒲桃中氨基酸组成与含量对其营养与风味的影响[J]. 食品科学, 2012(16): 204-207.
[19] 刘东娜, 郑晓娟, 卿钰, 等. 蒙顶山名茶游离氨基酸总量及组分的测定分析[J]. 四川农业大学学报, 2012(2): 190-194.
[20] 尹鹏, 刘威, 王广铭, 等. 茶树芽叶茸毛及茶毫研究进展[J]. 河南农业, 2016(27): 44-46.
[21] Ahmad W.Effects of nitrogen fertilization rate and harvest time on maize (Zea mays L.) fodder yield and its quality attributes[J]. Asian Journal of Pharmaceutical & Biological Research, 2012, 2(1): 19-26.
[22] Aroyeun S O.Crude fibre, water extracts, total ash, caffeine and moisture contents as diagnostic factors in evaluating green tea quality[J]. Italian Journal of Food Science, 2013, 25(1): 70-75.
[23] 赵璇, 李新生, 韩豪, 等. 汉中茶叶氨基酸含量测定及营养价值评价分析[J]. 氨基酸和生物资源, 2016(1): 17-23.
[24] Zhao M, Ma Y, Dai L L, et al.A High-Performance liquid chromatographic method for simultaneous determination of 21 free amino acids in tea[J]. Food Analytical Methods, 2013, 6(1): 69-75.
[25] 施兆鹏. 茶叶审评与检验[M]. 4版. 北京: 中国农业出版社, 2016: 59.
[26] Karak T, Bhagat R M.Trace elements in tea leaves, made tea and tea infusion: A review[J]. Food Research International, 2010, 43(9): 2234-2252.
基金
青岛农业大学高层次人才基金（631020）、青岛农业大学大学生科技创新项目、山东省高等学校国内访问学者项目
PDF(1000 KB)
浙公网安备 33019902000101号