Zijuan tea is a rare special tea in Yunnan.In this paper,amino acids and trace elements of Zijuan tea with different processing methods(baked green tea,sun-dry tea,black tea and fermented Pu’er tea) were studied by using liquid chromatography with pre-column derivation.The content of trace elements(Cu,Zn,Fe and Mn) was analyzed by atomic absorption photometry.The results showed that there were differences in species and content of free amino acids in tea product with different processing methods.Analysis of score of ratio coefficient of amino acid showed that there were differences in nutritional value of free amino acids in the same tea materials with different processing methods.Little difference was found in the contents of trace elements Cu and Zn in Zijuan tea with different processing method.However,the contents of Fe and Mn were significantly varied in the different tea samples.

The biochemical compositions in tea buds, first leaf, second leaf, third leaf, fourth leaf and tea-stalk were analyzed, which picked from the shoots of Yunkang 10 (Camellia sinensis), a kind of big leaf species. The results showed that the content of total ash, soluble sugar, iron (Fe), manganese (Mn) and fluoride (F) in tea buds were lower than those of tea leaves, the content of water soluble ash, crude fiber, copper (Cu), zinc (Zn), theanine and caffeine in tea buds were higher than tea leaves, and the content of tea polyphenols, water extracts and ester-catechins in tea buds were lower than young leaves but higher than old leaves. The content of total ash, water extracts, tea polyphenols, Cu, F, caffeine and catechins in tea-stalk were lower than buds and leaves, and the content of crude fiber, Fe and theanine in tea-stalk were higher than buds and leaves. The coefficients of variation calculated from the content of Cu, Zn, Mn, F, crude fiber, soluble sugars, theanine, caffeine and catechins were more than 15% in different tea buds and leaves, which suggested that biochemical compositions are very different in tea buds and leaves.

The aromatic components of Yunnan specific Zijuan sun-dry green tea and Zijuan basket-fired green tea were extracted by fully automated headspace solid-phase microextraction(HS-SPME),and were identified by gas chromatography-mass spectrometry(GC-MS). Then comparison difference with the regular Daye sundry green tea was made. Results showed that the aromatic components of Zijuan sun-dry green tea and Zijuan basket-fired green tea were very close,but more abundant than that of Daye sun-dry green tea. The major aromatic components in Zijuan sun-dry green tea were linalool,dihydroactinidiolide,3,7-octadiene-2,6-diol2,6-dimethyl,caffeine,6,10,14-trimethyl-2-Pentadecanone,beta-ionone,hexadecane,phytol,geraniol, linalool oxide,α-terpineol,the major aromatic components in Zijuan basket-fired green tea were phytol,caffeine, linalool, hexadecane, linalool oxide, dihydroactinidiolide, octadecane, jasmone, benzoic acid cis-3-hexenyl ester,nerolidol,heptadecane,while the major aromatic components in Daye sun-dry green tea were phytol, linalool,caffeine,beta-ionone,diisobutyl phthalate,6,10,14-trimethyl-2-Pentadecanone,hexadecylic acid, dibutyl phthalate,geranylacetone,etc.

The chemical composition of leaf and buds of Yunkang No.10 were studied.The result showed that the total ash,soluble sugar,Iron,Manganese,and Fluoride in buds is lower than that in leaf,while water soluble ash/total ash,crude fibre,copper,Zinc,Theanine and Caffeine in the buds is higher than in leaf.The tea polyphenols,water infusion and ester catechins in buds is lower than tender leaves while higher than old leaves.In tea stalk,the total ash,water infusion,tea polyphenols,copper,fluoride,caffeine and catechins is lower than in the buds and leaves,while the crude fibre,iron and theanine is higher than in the buds and leaves.

The distribution and changing characteristics and content of soil metals(As,Pb,Cd,Hg,Cr,Cu,Fe,Mn,Zn and Se) were studied,and the pollution indices were used to evaluate the soil environmental quality of 50 soil samples of 10 ancient tea gardens(hundreds of years or even thousands of years of cultivation).The results showed that the content of Fe and Mn were higher but that for Se was lower;the content of Pb(10.7～33.5 mg/kg),Hg(0.030～0.148 mg/kg),Cd(0.033～0.120 mg/kg),Zn(21.4～87.3 mg/kg) were low enough to meet the the first grade of State Environmental Quality for Soils;the content of Cr(15.4～98.5 mg/kg),As(12.2～33.1 mg/kg),Cu(13.6～43.4 mg/kg) were low to meet the the second grade of State Environmental Quality for Soils.The integrated pollution index for the soils of the ancient tea gardens was less than 0.7,which was in the "clean" grade.The ancient tea gardens meet the environmental conditions of the organic tea garden,and is suitable for the construction of organic tea gardens.

The recent advance in research of fragrance ingredients of Puer tea was described briefly. The fragrance ingredi- ents and its proportion in fermented teas is reported in accordance with its types （ black or green tea）, origins, storage time, dry method and cuhivars.

An analytical multi-residue method for simultaneous determination of 7 organophosphorus was developed.Pesticides were extracted from Pu'er tea with acetonitile,cleaned up on a column of graphite and L-gulonic acid-γ-lactone as an applying analyte protectants,then were determined by GC-FPD.The recovery studies were performed at 0.08 mg/ kg and 0.32mg/ kg,and the recoveries ranged from 76.8 % to 106.8 % with a relative standard deviations ranged from 4.1 % to 7.7 %,and the detection limit of the method ranged from 0.003 to 0.01mg/kg.The results showed that the L-gulonic acid-γ-lactone can provide a more accurate quantitation and compensate matrix-induced chromatophaphic response enhancement,and reduce the detection limit obviously.

This paper compared the two methods which are the Yunnan local standards DB53/T 216—2007 and the second method of GB/T 8313—2008 of determining the content of tea polyphenols.Result shows that the polyphenols content of GB/T 8313—2008 is lower than DB53/T 216—2007,the second method of GB/T 8313—2008 of the sample handling has been improved,and standard samples were measured and achieve the desired results.The content of polyphenols of 20 raw tea samples were more than 20%,the content of polyphenols of 20 cooked tea samples were lower than 15%.The results provide a reference for the national standard of Pu'er tea.

In this paper,according to the detection results of 2 000 Pu'er tea samples in the past three years,we comprehensively analyzed the Pu'er tea products quality in the Pu'er city,including the sense of Pu'er tea,physiochemical index(water content,total ash,water extracts,and tea polyphenols content),safety index(lead,rare earths,pesticide residues and microbiology indicators).

Five heavy metal ions including As,Hg,Pb,Cd and Cu were determined in soil of tea garden in Pu'er city,the pollution situation of tea garden soil was evaluated by the single factor pollution index and Nemerow pollution index,combining with the Criteria of Grade Ⅰof the National Standards for Soil Environmental Quality.The results showed that the single factor pollution index of As,Hg,Pb and Cd were all below 0.7,and that of Cu was 0.988,the integrated pollution index was 0.73.The quality of soil environment in tea garden was good on the whole,and it accorded with the soil environment quality standards of the organic tea garden.

The content of lead,cadmium and copper in tea standard material were determined.There were two pre-treatment methods as follows:dry digestion and microwave digestion.The measured values of tea sample which processed by these two pre-treatment methods were contrasted respectively.The results showed that the microwave digestion was accurate;the measured values of lead,cadmium and copper were in the standard value range,and good recovery,lead recovery was 93.3%~106.7%;cadmium was 95.2%~103.2%;and copper was 100.0%~103.2%.

This paper mainly discussed the application of HACCP system in the processing of Pu'er tea,and analyzed the possible hazards during Pu'er tea processing.The critical control point,critical limits,monitoring methods and corrective measures were determined,in order to provide reference to the application of HACCP system in Pu'er tea processing.

This paper is an example that the uncertainty of measurement for tea moisture content by direct drying.It was setup the mathematical model of measurement,and analyzed the different parts of uncertainty,and the combined uncertainty of measurement results were calculated.Through the analysis,it was set up an uncertainty evaluation method in laboratory,which can make the experimental results more objective and more accurate.