著者

光崎 龍子 坂口 和子 光崎 研一 高木 敬彦 森 真弓 鈴木 啓子

出版者

The Japan Society of Cookery Science

雑誌

日本調理科学会誌 (ISSN:13411535)

巻号頁・発行日

vol.32, no.4, pp.330-333, 1999

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The appropriate picking time for dokudami (Huttuynia cordata) tea is generally considered to be at the termination of the flower-like white involucre. Therefore, we classified the growth period of dokudami into the sprouting, seed setting, and true leaf stages, analyzed the contents of inorganic components at these stages, and analyzed contents of inorganic components in the leaves and flowers in the seed setting stage. In addition, the importance of the tea picking time was evaluated by a correlation analysis and principle component analysis.<BR>Among the inorganic components of dokudam i, the content of potassium was the highest, and the contens of calcium, magnesium, iron, manganese and zinc increased with growth. The content of copper was high in the flowers after diplophase parthenogenesis.<BR>Inorganic components increased at a potassium: calciu m ratio of about 6: 1 and at a manganese: magnesium ratio of about 80: 1. The calcium: potassium ratio changed inversely to the copper content that was observed in the flowers and in the true leaf stage.<BR>A principle component analysis revealed calcium, magnesium, potassium, manganese, and copper as the principle components.<BR>These appeared to be the principle inorganic components of dokudami and to increase due to diplophase parthenogenesis. A principle component analysis a ccording to the growth stage showed that the specificity of flowers could be estimated from two-dimensional scatter diagrams. The appropriate picking time for dokudami tea is empirically considered to be at the termination of the involucre, and the analysis according to the growth stage and the analysis of the flowers and leaves confirmed this. To improve the abnormal gustatory that is sensation associated with a modern diet or with insufficient intake of inorganic components by aged persons, dokudami tea brewed from a herbal plant provides a readily drunk remedy.