竹溪龙峰茶的品质特征、主要品质成分和矿物质含量分析

Analysis of quality characteristics,components and nutrient elements of the Longfeng green teas in Zhuxi

以竹溪县11个不同区域内所产龙峰茶为研究对象,从感官品质、主要品质成分及矿质元素方面进行分析归类。结果表明,不同区域所产龙峰茶外形、汤色和叶底较一致,而香气、滋味差异较大;化学成分分析表明,龙峰茶水浸出物、茶多酚、儿茶素、氨基酸、咖啡碱、可溶性糖、叶绿素含量分别为21.93%~44.78%、28.43%~34.23%、150.00~171.88mg/g、2.58%~3.75%、1.87%~2.52%、2.32%~3.07%和0.084%~1.129%。矿物质元素分析表明,龙峰茶氮、磷、钾、钙含量分别为5.47%~6.65%、0.410%~0.502%、0.966%~1.129%、0.097%~0.135%,镁、铁、铜、锌含量分别为603.13~855.39、50.55~71.25、8.46~10.86、22.91~36.51mg/kg。系统聚类分析表明,竹溪龙峰茶品质可分为4种类型,类型Ⅰ：氮磷钾含量高,氨基酸含量高,水浸出物丰富;类型Ⅱ：低营养元素和生化成分;类型Ⅲ：茶多酚和可溶性糖含量高;类型Ⅳ：钙镁含量高,咖啡碱和儿茶素总量高。

The organoleptic quality, main chemical compositions and nutrient elements of Longfeng green teas coming from 11 areas were analyzed. The results showed that the shape, liquor color and re- fused leaves of all Longfeng teas had no difference, but the flavor and taste were different. The contents of biochemical composition and nutrient elements also had marked difference. The contents of tea bio- chemical composition： tea polyphenols 28. 43%-34. 23%, amino acids 2. 58%-3. 75%, caffeine 1. 87%- 2. 52 %, soluble sugar 2. 32%-3.07 %, chlorophyll 0. 084 %-0. 129 %, water extract 21.93 %-441 78~, cat- echins 150. 00-171.88 mg/g. The contents of elements： total N 5. 47%-6. 65% ,total P 0. 410%-0. 502%, K 0. 966%-1. 129%,Ca 0. 097%-0. 135%,Mg 603. 13-855.39 mg/kg,Fe 50. 55-71.25 mg/kg,Cu 8. 46- 10. 86 mg/kg,Zn 22. 91-36. 51 mg/kg. The Longfeng green teas could be divided into four types accord- ing to the systematic cluster analysis： the first type（Qianjin, Longwangya, Qichang, Shuangzhuyuan, Da- ping） with high contents of N, P, K, amino acids ing,Jiuligang） with the low contents of nutrient and water extract; the second type（Luohe, Qingcaop- element and biochemical compositions; the third type （Wangjiashan） with high contents of tea polyphenols and soluble sugar; the fourth type（Qinglongzhai, Meiziya） with high contents of Ca,Mg,caffeine and catechins.