The Research Of Tea Analysis In Wuyi Mountain

In this paper,Wuyishan green tea,oolong tea and black tea in some chemical components were studied.Respectively using Kjeldahl method to measure the protein content of the tea; Using automatic amino acid analyzer to detect tea amino acid content;using ultrasonic to extract lutein,determination lutein in tea by High Performance Liquid Chromatography;Using inductively coupled plasma mass spectrometry determination trace elements in Tea.Applying Kjeldahl method,the protein of Wuyishan green tea,oolong tea and black tea was determined,according to the experimental results can be obtained,the highest protein content of green tea,oolong tea lowest protein content,protein content of several tea have not difference in the samples.Detecting the 17 kinds of amino acids by Automatic amino acid analyzer in Wuyishan green tea,oolong tea and black tea.The measurement results for green tea.oolong tea and black tea produced in the Wuyi Mountain do not contain glycine,cysteine,methionine.However,green tea,oolong tea and black tea all contain lysine, phenylalanine,threonine,isoleucine,leucine,valine these types of essential amino acids.The total amount of amino acids in green tea is the most.Using ultrasonic extraction method to extract lutein in the Wuyishan green tea,oolong tea and black tea.Experiments were optimized,solvent extraction,ultrasonic time and ultrasonic temperature,optimal extraction conditions of this experiment is that the solid-liquid ratio is 1:25,ultrasonic temperature is 25 ℃,extraction time is 15 min and 95% ethanol solvent.Extraction using C18 column,the mobile phase for HPLC is methanol and measured at 450 nm by high performance liquid chromatography for lutein extraction.The lutein content of the 3rd Dahongpao is the highest 1.5184 mg / g,followed is the green tea.The lutein levels of oolong tea and black tea produced in Wuyishan are low.Microwave digestion method has been used to pretreat Wuyishan green tea,oolong tea and black tea,application the trace elements by inductively coupled plasma mass spectrometry.The variation of the method is 1.16%-3.90%.By the results,produced in Wuyishan green tea contains zinc,selenium,molybdenum,chromium,iron,manganese,nickel more than oolong tea and black tea in Wuyi Mountain,and the content of copper in the black tea is the highest.