The Study Of Chromatographic Fingerprint Of Instant PU-ERH Tea And Applications Of Chemometric Methods

Pu-erh tea is a unique post-fermented tea, which is derived from the leaves and buds of broad-leaf variety of the tea plant by heating, rolling, sun drying and pile-fermentation. Recent studies have demonstrated multifaceted benefits of Pu-erh tea including anti-oxidative, anti-mutagenic, antibacterial, antiviral, anti-tumor, cholesterol-lowering, anti-obesity, hypoglycemic and anti-allergic activities. As a kind of functional tea drink, it has been paid more and more attention by domestic and foreign consumers in recent years. With the popularity of Pu-erh tea, the instant Pu-erh tea has become a favorite products that many companies competing to develop and produce. As a deep-processing tea product, consumers of instant Pu-erh tea tend to be more enthusiastic about the brand, product taste and quality assurance, which is different from the requirements of material Pu-erh tea including the tea trees planting areas, crude or ripened tea, old tree or terraced tree. This requires the instant pu-erh tea producer possess a more strict and effective quality control method to ensure the stability and consistency of different batches of product. At the same time the enterprise also need to be able to maintained the unique properties of their own products from other manufacturers of competing products, so as to achieve better publicity and authenticity of identification, in order to prevent unscrupulous traders producing or selling shoddy, infringing upon the rights of informal enterprises and consumers. Currently, fingerprint technology is a focal point in the research of traditional Chinese medicine. It has been relatively mature for research of traditional Chinese medicine or other complex multicomponent systems, draws on the experience of Fingerprinting techniques In this paper we draws on the experience of Fingerprinting techniques of traditional Chinese medicine to analyze the instant Pu-erh tea.1. A method based on high performance liquid chromatography was developed for chemical fingerprinting analysis of instant Pu-erh tea. In the fingerprint,10 representative constituents including catechins, gallic acid and so on was determined by retention time qualitative method. The methodology study was performed to evaluate the established HPLC method for fingerprinting analysis. The result shows that the HPLC method was applicable for the analysis of instant Pu-erh tea with good stability, high precision and repeatability. Using this method, the common fingerprint of 23 different kinds of instant Pu-erh tea from 20 brands including brand DEEPURE was established. And the fingerprint was initial analyed.2. Chemometric pattern recognition method was utilized for different types of insant Pu-erh tea systematic analysis. Firstly, the similarity analysis was used to respectively analyze three kinds of different batches Deepure instant tea, including 34 batches of Qingxiang type,44 batches of ganchun type and 19 batches of Gucha type, with the appropriate type of standard sample as a reference fingerprint. The results showed high quality and stability of different batches of Deepure instant Pu-erh tea, mostly reaching more than 0.9 similarity. There were 94%,90.7% and 88.7% of the batches of the three type of Deepure instant tea reached more than 0.9 similarity. Then with the three type of Deepure standard instant tea as reference fingerprint,20 kinds of istant Pu-erh tea from 19 manufactures was analyzed by similarity analysis. The result showed that similarities are lower than 0.9, indicating that the similarity analysis was capable to clearly distinguish the competing products and Deepure instant tea.15 maker constituents were selected as the main chemical markers for the principal component analysis of Deepure and competing products, which importantly contribute the classification instant Pu-erh tea samples. Furthermore, competing products and Deepure instant tea samples were accurately classified by principal component analysis and discriminant analysis. This further validated the developed methodology can provide basis for quality control and classification of instant Pu-erh tea.