Studies On The Dissolution Properties Of The Medical Stone And The Green Tea Prepared From Its Mineral Water

The dissolution properties of the Medical Stone and the technical parameters of the green tea prepared from the Medical Stone mineral water were studied in this paper. The best dissolution conditions of the Medical Stone aqueous solution were obtained by the analysis of its electric conductivity. Most indexes of sample water were discussed and contents of the mineral elements in the tap water, the mineral water and the water extracted by the Medical Stone were determined. The influence of different water and metallic ions on the tea liquor was discussed by the analysis of the content of TP and the value of CIE( 1976) L and AE. The optimal combination of chelating agent and anti-oxidant was determined by the Uniform Design. The three key factors were found by the Plackett-Burman Design and the optimized level was achieved by the Response Surface Methodology. Experiment results indicated that the total hardness, the degree of mineralization and the electric conductivity between the tap water and mineral water were by far the maximum. Trace elements such as Li, Sr, Ge and Se were found in the Medical Stone mineral water. The TP, Gua, water-solubility pigments and the value of L and AE were affected significantly by the water. Among the metal ions, Ca> facilitated the forming of the tea cream, Fe2 Fe3 made the tea liquor brown and low concentration of Al3 21 would improve the tea quality. Other additives such as f3 -CD.. NaHSO3.. CMC could also increase the value of L and the three key factors which had the biggest reliability in the Plackett-Burman Design were Vc, EDTA-2Na and CMC. The optimal technology of the green tea beverage prepared fromthe Medical Stone were as follows: operating temperature, 7OC; infusing time, 6mm; green tea to mineral water, I 150; EDTA.-2Na, 0.055%; Vc, 0.025%; NaHSO3, 0.01%; J3 -CD, 0.05% and CMC, 0.0l6%...