Abstract:Along with the increase of the national and international demand for tea，the pesticide residues in tea and the related detection methods also occupy an important position in the food safety control gradually. Because of the different physical and chemical properties，different kinds of pesticides have diverse detection methods. Study the corresponding detection methods according to the characteristics of pesticides in tea is of great significance. In this paper，the main categories of pesticide residues and their detection methods in tea，which are limited by domestic and international standards，are reviewed. Meanwhile，combining the latest detection technology，the paper prospects the future development and research direction of tea pesticide residue detection，which provides a theoretical basis for the establishment of new testing standards.

Abstract:In this thesis，tyrosine 211 of γ-CGTase from Bacillus sp. G-825-6 changed into leucine based on site-directed mutagenesis. The influences of substrate type，concentration，time，temperature，and enzyme concentration on the mutant Y211L catalyticed starch to produced γ-CD were evaluated. On the basis of single of factor experiments，orthogonal design method was used to optimize the condition for production of γ-CD. As a result，the best condition was：cassava starch 6%，enzyme concentration 4 u/g，temperature 50 ℃，time 24 h. Under thses conditions，the production of γ-CD can reach 14%. If the total cyclodextrin content is 100%，the catalytic production ratio of γ-CD is 97%.

Abstract:In order to search for a rapid technique for the isolation of polymeric polyphenols from Chinese rice wine for solving the problem that accurately measured the polyphenols in Chinese rice wine because of the impurity interference and low target content. in this paper，the effects of recoveries for the 9 kinds of polyphenol compounds were evaluated by the condition of mobile phase and SPE cartridge types as well as the composition of eluent and the volume of eluent by a high-performance liquid chromatographic method with ultraviolet detection，in the end，using this method for determination polyphenol content in different sweet type of shaoxing Chinese rice wine for precise measurement. Results show that the recovery were between 87.3%~103.8% and the RSD less than3.2% when the Poly-Sery HLB SPE cartridges were used and methanol as eluent and the elution volume for 3 times on the sample volume . catechin and Syringic acid has the highest content in different sweet type of shaoxing Chinese rice wine，the content of polyphenol in dry type and half dry type is lower than the sweet type and half sweet type Chinese rice wine .This SPE method is simple，rapid，and accurate. It can be satisfactorily applied to the determination of polyphenol compounds in wine drinks.

Abstract:A mutant strain，which was named X. campestris WXLB-006 and could use glycerol for xanthan production，was obtained by adaptive evolution. RT-PCR results showed that the transcriptional level of genes related to glycerol metabolism（/i>glpF，glpK，glpD，and fbp ） in X. campestris WXLB-006 was higher than those of the parent strain，and the order of these four genes was glpD （8.53） > glpF （7.64） > glpK （6.61） > fbp （5.79）. With low glycerol concentration（40 g/L），adoption of variable aeration rate and stirring speed（0～24 h，0.5 vvm and 200 rpm；24～60 h，1.0 vvm and 400 rpm），and three-stage varied speed feeding glycerol strategy（24～34 h，3 g/L/h；34～44 h，2 g/L/h；44～54 h，1 g/L/h），biomass increased from 1.65 g/L to 1.94 g/L and xanthan yield from 17.8 g/L to 33.9 g/L，but fermentation time decreased from 120 h to 60 h. Importantly，xanthan gum produced from glycerol has the properties of low viscosity，high transparency，fast hydration rate，and increased viscosity after treated with -20 ℃ freeze-thaw cycles.

Abstract:In this paper，magnetic mesoporous silica （MMS） was prepared by using rice husk ash as the silica source and Fe3O4 as the magnetic material，and then MMS was modified by TMMPS as the silane coupling agents. The effects of agitation time，reaction temperature and the amount of ammonia on the surface thiohydroxy concentration were investigated during the preparation process and the effect of surface thiohydroxy concentration on the adsorption capacity on Cd2+ was investigated during the adsorption process. At last，the end product named thiohydroxy modified magnetic mesoporous silica （TMMS） and MMS was characterized and the adsorption effect of MMS and TMMS for Cd2+ was compared by adsorption isotherm. It was found that when the reaction condition was 8 h at 80 ℃ and the amount of ammonia was 750 ?滋L，the surface thiohydroxy concentration of TMMS was 0.131 mmol/g. The adsorption effect was in direct proportion to the surface thiohydroxy concentration. The BET surface area of MMS and TMMS was 581.769 m2/g and 405.665 m2/g respectively. The isotherm had a good correlation with Langmuir isotherm model rather than Freundlich isotherm model，which suggesting that the adsorption was monolayer adsorption. When the reaction temperature during the adsorption process was 30 ℃，the saturated adsorption capacity of TMMS was 33.33 mg/g，which was bigger than the value of MMS. Therefore，the purpose of effective removal of Cd2+ in wastewater can be achieved by modification.

Abstract:Gelatin was extracted from salmon skin by acid leaching and water extraction. Ultraviolet spectrum with the maximum absorption wavelength was 233 nm，and amino acid composition testified that the extract conformed to the characteristics of gelatin. The gelatin extract rate was 60.46%，and the gelatin content in the extract was 83.92%. Papain was used for enzyme hydrolysis of gelatin to become collagen peptides which were low molecular weight. The effects of hydrolysis time，amount of enzyme，substrate concentration，pH and temperature on hydrolysis rate were investigated systematically. By orthogonal designed experiments，results showed that the optimal conditions of enzymatic hydrolysis was hydrolysis time 2.5 h at 55 ℃，amount of enzyme 7%，substrate concentration 10%，pH 8.0. At the optimum conditions，the hydrolysis degree was 12.65%. The collagen peptides from salmon skin had low molecular weight，whose molecular weight less than 1000 Da accounted for 91.5%.

Abstract:Chitosan-gelatin composite films were prepared. The effects of chitosan oligosaccharide on gelatin-chitosan composite films were evaluated. The mechanical，antioxidant，antibacterial properties and preservation of beef of the composite film were evaluated. The results showed that the tensile property of the film was increased，but the other mechanical properties were decreased. The antioxidant property and the antibacterial property of the film were improved greatly. The preservation effect of chitosan/gelatin/chitosan oligosaccharide composite film was improved greatly. The shelf life of beef can be extended for 6 days by chitosan oligosaccharide.

Abstract:In this study，waxy rice starches（WRS） were isolated from the developing waxy rice seeds that were harvested at pollination stage for 11，13，15，17，22，27，and 35 days. The structural properties，including the shape，the crystallites，and molecular structure，were studied to find the change law of starch structure during pollination stage. The results，obtained from scanning electron microscope（SEM） and laser particle size analyzer（LPSA），showed that the spherically immature starch particles gradually disappeared and powder particle size of the peak increased from 5.92 μm to 6.77 μm. The XRD data indicated that the relative crystallinity increased from 31.0% to 37.5% during pollination stage. Molecular structure analysis suggested that the weight-average molecular weight（Mw） and the number-average molar mass（Mn） were the higher for the increased side chain during later pollination stage. WRS isolated from later pollination stage was easier to gather together after gelatinization.

Abstract:The objective of this study was to evaluate the effects of high-temperature cooking of pan-frying，frying and broiling on hazardous substances of goat meat by regulating the cooking time and temperature. The spectrophotometry，gas chromatography-mass（GC-MS） and high performance liquid chromatography（HPLC） were used to measure the contents of nitrite，trans-oleic acids（C18：1 trans-9） and polycyclic aromatic hydrocarbon（PAHs） respectively. The results showed that the content of nitrite in the processes of 2 min and of 3 min were lowest. There were no significant differences in C18：1 trans-9 content for pan-frying time（p >0.05）. The contents of phenanthrene，pyrene and dibenz[a，h] anthracene in the processes of 2 min and 3 min pan-frying were lower（p <0.05）. For frying，the contents of nitrite，C18：1 trans-9，pyrene，benzo[k] fiuoranthnen，benzo[a] pyrene and dibenz[a，h] anthracene in the process of 3 min were lowest respectively（p <0.05）. For broiling，the content of nitrite in the process of 160 ℃ was lowest（p<0.05）. The content of C18：1 trans-9 in the processes of 160 ℃ and 180 ℃ were lower. The contents of naphthalene，phenanthrene and benzo[a] pyrene in the process of 160 ℃ were lower than those in 180 ℃，and the contents of phenanthrene，chrysene，benzo[k] fiuoranthnen and benzo[a] pyrene were lower than those in 200 ℃（p <0.05）. A comprehensive analysis indicated that the three high-temperature cooking methods had a great influence on the hazardous substances of goat meat. At the temperature of 226~228 ℃，the goat meat were pan-fried for 2~3 min and fried for 3 min respectively，and broiled for 40 min under the temperature of 160 ℃，which had a lower hazardous substances.

Abstract:The Saccharomyces cerevisiae FM-S-115 strain has good function in degradation L-malic acid，in order to play a good role in degradation L-malic acid of FM-S-115 strain during wine fermentation，the main influence factors and mathematical relational model between deacidification ratio and main influence factors were analyzed using univariate analysis and Central Composite Design experiment. The results showed that fermentation temperature，inoculation amount and SO2 concentration were the main influence factors on the deacidification ratio of FM-S-115 strain，the optimum conditions were the fermentation temperature 26.26 ℃，the inoculation amount 5.15% and the SO2 concentraion 81.08 mg/L．The experimental values of deacidification ratio of FM-S-115 strain was 38.11%，which well matched with the response surface methodology predicted values．

Abstract:The stability of blueberry anthocyanin is influenced by processing conditions. To develop and utilize blueberry anthocyanin，the effects of pH，temperature，light，metal ions，Sucrose，potassium sorbate，sodium citrate，ascorbic acid and tea-polyphenol were studied. The results showed that the effect of pH on anthocyanin stability was significant，and the stability was relatively better at pH<3.0；high temperature damaged the stability，while the effect was less below 60 ℃；light accelerated the degradation of blueberry anthocyanin；Na+，K+，Zn2+，Ca2+ and Mg2+ of 10 mmol/L improved the the stability，but Fe3+ and Cu2+ had less stability；sucrose is no significant effect lower than 50 g/L，but the high concentration improved the stability；potassium sorbate of 0.01~0.08 g/L had no significant effect；sodium citrate decreased the stability while the concentration in the range of 0.25~2.00 g/L，ascorbic acid and tea-polyphenol significantly improved the stability with co-pigmentation effect.

Abstract:Qiandongnan prefecture of Guizhou province has become largest organic blueberry production base in China，However，most of the species were harvested in high temperature and high humidity in July，seriously shorten the storage period of fresh fruit，brings the huge economic loss for the off-season. Juice processing properties of eight varieties from Qiandongnan Prefecture of Guizhou Province were analyzed in terms of appearance morphology，physical-chemical properties，nutritional components，antioxidant activity and juice characteristics by principal component analysis（PCA），and sorted the comprehensive grade. The results indicated that there was a certain degree of differences among different cultivars. The PCA results showed that the cumulative contribution proportion of the former five principal components was 85.509%，the first principal component is mainly fruit weight，a*，b*，pectin and protein；the second principal component is the longitudinal diameter，viscosity，reducing sugar，total phenolic and flavonoids content；the third principal component is titratable acid；the fourth principal component juice TSS；the fifth principal component is the juice yield and anthocyanin content. The comprehensive evaluation of the juice processing properties of 8 blueberry varieties was as followed：Tifblue，Premier，Bright Well，O'neal，Powderblue，Blue Rain，Climax，Gardenblue. Tifblue ，Premier and Bright Well is appropriate processing into juice and wine products.

Abstract:Four kinds of commercial yeasts commonly used in production were selected，such as D254，RC212，BDX and F15. CIELab color space parameters，chroma，hue，total color of pigments，polymeric pgements color and monomer anthocyanins of Cabernet gernischt wine during natural yeast autolysis by ageing on lees. The color evolvement and correlation analysis was studied.Principle component analysis（PCA） of the date indicated that WC，WCP，PPC and CI of BDX，D254，RC212 yeast by ageing on lees improved to varying degree. And A280 and monomer anthocyanins of all the wines samples increased. Hue and Hab was related positively，and were negatively with other indexes. The other index was related positively. The content of color and color stability of wine by ageing on lees can be improved.

Abstract:In order to recycle by-products of fruit and vegetable，watermelon rind was used to prepare edible film with sodium alginate as thickener and glycerol as plasticizer via flow-casting method. The effects of the content of watermelon rind，sodium alginate and glycerol on the sensory qualities，tensile properties and barrier properties of the films were investigated. The results showed that the optimal formula to prepare edible watermelon rind based films was 55% watermelon rind（w/w），0.35% sodium alginate（w/w） and 0.20% glycerol（v/v）. At this optimal formula，the comprehensive performance of the edible film is 90 point in sensory qualities，0.072 mm in thickness（T），18.09 MPa in tensile strength（TS），18.92 % in elongation at break（E），3.068×10-12 g·cm/cm2·s·Pa in water vapor permeability（WVP） and 4.042×10-17 cm3·cm/cm2·s·Pa in oxygen permeability（OP），respectively. Moreover，the edible watermelon rind based films could prolong shelf life of figs to some degree，which have potential applications such as keep-fresh packages for fruits and vegetables.

Abstract:In order to study the structure and function of TPS family genes in Ipomoea batatas，7 Ib TPS family genes were identified and their sequences，structures and functional properties were determined by bioinformatic method. These Ib TPS genes were divided into class I and class II subfamilies according to their structure and phylogeny relationship. In this study，the complete IbTPS7a gene cloned from Ipomoea batatas contains an open reading frame（ORF ） of 2 568 bp. Meanwhile，Ib TPS7a was transformed into E. coli BL21（DE3） and Saccharomyces cerevisiae INVSc1，respectively. The results indicated that over-expression of IbTPS7a conferred recombinant strains better growth or survival rate than control strain. Digital gene expression profiling（DGE） proved that the expression level of Ib TPS7a has a difference in different tissues，the highest transcription level of Ib TPS7a was in stem and the lowest level was in fibrous root. The results indicated that IbTPS7a gene family existed in sweet potato and Ib TPS7a was helpful to enhance cell resistance to abiotic stress.

Abstract:Headspace solid phase microextraction（HS-SPME） and gas chromatography-mass spectrometry（GC-MS） were used for the analysis of volatile components of the Mytilus edulis in the ocean region around Shengsi Gouqi Island，as well as its genital glands，digestive glands and muscle. The results showed that，29 volatile components were identified in the edible part of mutilus edulis，and aldehydes（47.48%），ketone（11.86%），alcohols（15.52%） were predominant. These compounds caused the particular flavor of mytilus edulis. Propanal，pentanal，2，4-pentadienal，3-heptanone and petanol had relative high content and low threshold value with particular flavor，which made the great contribution to the flavor of mytilus edulis. They may be the characteristic flavor compounds. The results also indicated that，different parts of the mytilus edulis make different contribution to the flavor. The content of aldehydes and ketone in genital glands were 59.75%，which is the main part affecting the characteristic flavor. The influence caused by the muscle and genital glands was less.

Abstract:Amylases were used to hydrolyze tobacco waste，and amino acid was added to the concentrated hydrolysate solutions for Maillard reaction to the preparation of cigarette flavoring. By single factor experiment，the optimal enzymatic hydrolysis conditions were determined as follows：the amylase 0.2%，beta amylase 3%，reaction time 7 h，pH5.4，temperature 50 ℃；verified experiment shows that the enzymolysis solutions of the quality volume concentration of reducing sugar increased by 28.07%. Amino acid was added into Mallard reaction solutions，and the optimal conditions of Maillard reaction were as follows：pH 8，reaction temperature 115 ℃，reaction time 5 h，the moisture content of the reaction system 15%. By the analysis of GC/MS，a total of 100 kinds of chemical components were identified in Maillard reaction products. Among them，there were 57 kinds of compounds which related to tobacco aroma，accounting for 71.277% of the total content.