Gajewska R, Nabrzyski M, Ganowiak Z, Cybulski M, Kułakowska D
Katedra i Zakład Bromatologii Akademii Medycznej 80-416 Gdańsk.
Rocz Panstw Zakl Hig. 2000;51(3):251-8.
The paper contains the results of 19 minerals (Ca, K, P, Na, Mg, Zn, Fe, Mn, Cu, F, Ni, Co, Cr, Li, Sr, Al, Cd, Hg, Pb) determined in green and black species of market teas. The examined minerals (except phosphorus, fluoride and mercury) were determined by ASA-method using air-acetylene flame (aluminium was determined in the nitrous oxide-acetylene flame). Mercury was determined by cold vapour method. The phosphorus and fluoride was determined by spectrophotometry methods (phosphorus in the form of phosphomolybdate blue and fluoride by use microdiffusion procedure where alizarin-fluoride complex was formed). It has been found that the examined teas are important source of potassium and low source of sodium, assuming a daily intake of 4 glasses of tea infusions. Tea drinking may be advantageous for hypertensive persons. The investigated teas are also important source of other examined minerals especially some microelements. The intake of the toxic metals with tea (Cd, Hg, Pb, Al) is low, from a centesimal to a few percent of the PTWI dose accepted by the FAO/WHO Experts. This paper presents also the first findings of the lithium and stronthium contents of examined tea species--whose physiological role still remains unknown.
该论文包含了市售绿茶和红茶中19种矿物质（钙、钾、磷、钠、镁、锌、铁、锰、铜、氟、镍、钴、铬、锂、锶、铝、镉、汞、铅）的测定结果。所检测的矿物质（除磷、氟和汞外）采用原子吸收光谱法（ASA法），使用空气 - 乙炔火焰进行测定（铝在氧化亚氮 - 乙炔火焰中测定）。汞采用冷蒸气法测定。磷和氟采用分光光度法测定（磷以磷钼酸蓝形式测定，氟采用微扩散程序测定，形成茜素 - 氟络合物）。研究发现，假设每天饮用4杯茶，所检测的茶是钾的重要来源，而钠的来源较少。饮茶对高血压患者可能有益。所研究的茶也是其他检测矿物质特别是一些微量元素的重要来源。通过茶摄入的有毒金属（镉、汞、铅、铝）含量较低，占粮农组织/世界卫生组织专家认可的每日允许摄入量（PTWI）剂量的百分之一至百分之几。本文还展示了所检测茶种中锂和锶含量的首次测定结果——其生理作用仍然未知。
