The Research Of Inspection Method (hplc Method) For Catechin Compound And Free Amino Acid In Pu'er Tea

Catechins compounds are important bioactive substances in tea, content of about 70% of the total tea polyphenols. They are important materials which affect the color and taste of tea, so the research on its method of detection is of great significance, by which we can identify the quality of Pu'er tea and study the tea flavor mechanism. We established a rapid and accurate method of analyzing and determination of catechins by high performance liquid chromatography when we explored the Pu'er tea samples pre-disposing method and optimize the conditions for the instrument. The method can simultaneously determine nine components in tea, including D-catechin (+C), epicatechin (EC), epigallocatechin(EGC), epicatechin gallate (ECG), epigallocatechin gallate (EGCG), gallocatechin (GC), catechin gallate(CG), gallocatechin gallate (GCG)and gallic acid nine components in tea. The separation of each component was ideal, and with a good linear relationship. The method is rapid, accurate, reproducible and suitable for the qualitative and quantitative analysis of nine components of.catechins in the Pu'er tea.Amino acid is one of the basic materials in organisms. It is also one of primary chemical components of tea and the important component of tea taste. Thus, analyzing and determining the free amino acid content in tea is very necessary. Now we has found 26 kinds of amino acids in tea such as theanine, glutamic acid, arginine, serine, etc., in which theanine accounts for more than 50% of total amino acids and is characteristic amino acids in tea. The composition and content of amino acid, and their degradation products and transformation products, as well as the proportional relationship between these components in tea will directly affect the aroma and taste of tea, which play important roles in the quality of tea. Therefore, the analysis and research of amino acid in tea is of great significance for the quality accreditation of tea. In this paper, the Pu'er tea was selected as the research object, a rapid and accurate analyzing determination method of amino acids by high performance liquid chromatography was established, by which 18 kinds of amino acids in the Pu'er tea can simultaneously be determined. The separation of each component was ideal, and with a good linear relationship. The method is rapid, accurate, reproducible and suitable for qualitative and quantitative analysis of 18 kinds of amino acids in the Pu'er tea.This paper provided a technical support for further clarifying the mechanism of flavor of tea in the next step, the construction of Pu'er tea standard system and the research of the quality of identification technology of Pu'er tea by the research in the method for analysis and determination of catechin compounds and free amino acids in the Pu'er tea, which is of great theoretical significance and practical value.