茶葉中微量元素濃度與環境因子關聯性之探討

Environmental Implications of Trace Element Concentrations in Tea

張正達(Jan-Dar Chang) ； 游鎮烽(Chen-Feng You)

《國立臺灣博物館學刊》 64卷2期 (2011/06) Pp. 1-16

摘要

茶樹因吸收不同區域的土壤及天水，其所含特徵元素亦不盡相同，故可藉以了解其產地，並可應用於判別茶葉標示之產地是否正確的依據。分析結果顯示，不同區域茶樹的生理必需元素濃度相近(如N、p、K、Ca、Mg、S、Cu及Al等)，顯示因茶樹種屬問所引起的元素選擇性對於茶葉並不顯著;然而Ba及B的濃度則呈現極端的差異，可能與不同地區的土壤或天水的性質，或與不同來源的貢獻比例有關。本研究藉由主成分因子分析來釐清各元素分佈之主要影響及次要影響的因子，並依據文獻推論其來源所代表之意義。前人的研究指出的所代表的是污染的指標，因此三峽與凍頂山海拔較低所受到的污染也相對較嚴重(三峽= 3.955 p pb、凍頂山= 3.925 ppb)，其次為杉林溪(杉林溪= 2.173 ppb)之後才是潽洱茶、武陵與阿里山(潽洱= 1.813 ppb、武陵= 1.230 ppb、阿里山=1.819 ppb)，最後才是奇萊山(奇萊山= 0.533 ppb、)，武陵海拔雖高於杉林溪但其Pb卻較高，推測可能是該地區為觀光景點，車輛污染較為嚴重所致。中低海拔茶區則B的含量較高，可能與其相對離海距離較近有關(三峽= 103.9 ppb、凍頂山= 103.3 ppb、阿里山= 140.5 ppb、潽耳=131 ppb)，因在高海拔茶區其B含量皆較低(奇萊山= 72.45 ppb、杉林溪=66.65 ppb、武陵=78.94 ppb)。茶葉中的幾乎看不到。本研究之分析結果，就環境而言將可系統性的評估茶葉的微量元素含量以及可能的攝取來源，並提供相關研究作為參考。

關鍵字

茶葉 ； 微量元素 ； 茶湯

並列摘要

Various trace elements and compounds in nature environments are utilize d during plant growth. It is, therefore, possible to use the fingerprints of these elements in plants to identify potential makers of different tea products locally and worldwide. Previous studies have shown that N, P, K, Ca, Mg, S, Cu and Al in plant extraction showed no distinguishable pattern. In contrast, Ba and B do show large variation at different localities, possibly affected by groundwater, soils or meteoric contributions. Th is study aims to use statistical methods to categorize major and trace element distributions in tea products collected from various locations and to understand possible causes that affect ing the distribution of elemental patterns in tea leaves. Pb is a common air-pollution ind icator and is sensitive to the degree of anthropogenic influence. In the study area of Shanshia and Dongding Mountain, located just above sea level , have the highest Pb concentration in tea extraction (Shanshia, 3.96 ppb and Dongding, 3.93 ppb) . The Shanlinshi tea, Puer tea, Wuling tea, Ali Mt. and Chilai Mt. has 2.17, 1.81, 1.23, 1.82 ppb and 0.53 ppb , respecti vely. Although Wuling tea grows at high altitude, the Pb concentration is higher than Shanlinshi, that possibly due to heavy tourist activity. Sea salt is a major source for B, areas with low altitude and close to the coastal region cou ld receive more B. For instance, tea from Shanshia, Dongding, Ali Mt. and Puer has 104, 103, 141 and 131 ppb, re spectively, whereas high mountain tea show low B in Chilai Mt., Shanlinshi and Wuling, 72.5, 66.7 and 78.9 ppb, respectively. Only trace amount of As found in tea products examined. In summary, this study systematically evaluated possible source of elemental patterns in tea that is daily consumed in Chinese society and in Asian counties.

並列關鍵字

tea ； trace element ； tea infusion

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