Abstract:The history of food processing and human progress come down in one continuous line. And food processing is meeting demand for food constantly. So， food processing is necessary in human progress and it is realistic memory of human civilization. Under the influence of commodity economy and misunderstanding of food processing， food industry pursues ultra-processed food in order to get high profits， and in this process food industry ignores sustainable development of human health and the environment， which causes ultra-processed foods are popping up on the market. And this brings new challenges to the transformation and development of food industry. The relationship between the degree on food processing， human health and social and economic development needs to be considered and studied. In order to accomplish the sustainable development of food and promote the continuous progress of social civilization and human nutrition and health， the significance and necessity of food processing to food safety and human health would be understood scientifically. Besides， the potential harm of "excessive" food processing should be realized and solved.

Abstract:In the present work， the protective effect of corn glycopeptide intervention on alcohol-induced injury of LO₂ cells was studied， and the possible mechanism of corn glycopeptide antagonizing alcoholic liver cell injury was investigated. The results show that compared with the alcohol model group， corn glycopeptide at 50 μg/mL remarkably increased the activities of alcohol metabolism enzymes (ADH and ALDH) and antioxidant enzymes (SOD， CAT and GSH-Px) as well as GSH content， decreased ROS and MDA levels in damaged LO₂ cells. These results suggested that corn glycopeptide could enhance cytomembrane structural integrity by promoting alcohol metabolism and enhancing antioxidant activities， prevent the leakage of liver enzymes (AST， ALT and LDH) and reduce the percentage of early apoptosis and death of LO₂ cells to achieve the effect of protecting the LO₂ cells induced injury by alcohol.

Abstract:In order to study the anti-inflammatory effect of Antarctic krill oil， the LPS-induced RAW264.7 cells were taken as the inflammatory model， the anti-inflammatory ability of Antarctic krill oil was evaluated by cell morphology， cell phagocytosis， myeloperoxidase(MPO) activity and pro-inflammatory cytokines (TNF-α， IL-1β and IL-6)， and its anti-inflammatory mechanism was preliminarily studied by the genes expression of pro-inflammatory cytokines and key inflammatory enzymes (iNOS and COX-2). The results showed that Antarctic krill oil could significantly alleviate the cell differentiation induced by LPS， inhibit the increase of cell phagocytosis， MPO activity and the secretion of inflammatory factors (especially TNF-α). The qRT-PCR detection indicated that Antarctic krill oil could significantly quell the activation of key inflammatory enzymes and inflammatory factor genes induced by LPS. This study shows that Antarctic krill oil has anti-inflammatory activity， which is related to its regulation of iNOS and COX-2.

Abstract:Objective: A C2C12 myotube cell insulin resistance (C2C12-IR) model was established to explore the effect of isothiocyanate extracted from Moringa oleifera (MIC-1) on C2C12 myotube cell insulin resistance. Methods: Palmitic acid (PA) was used to induce C2C12 myotube cells to establish a stable C2C12-IR model， and the cells were treated with different concentrations of MIC-1 (0， 2， 4， 8， 16 μmol/L) for 16 h. The cell viability of C2C12-IR cells was detected by MTT assay， and the effect of MIC-1 on glucose metabolism of C2C12-IR cells was observed. Cellular oxidative damage [nitric oxide (NO)， malondialdehyde (MDA) and glutathione peroxidase (GSH)] were tested. The expression levels of related proteins in the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway were detected by using Western blot assay. Results: The optimal modeling conditions for the C2C12-IR model were determined， that is， C2C12 myotube cells were treated with 0.5 mmol/L PA for 16 h. Compared with the C2C12-IR group， MIC-1 significantly increased the glucose consumption and glycogen content of C2C12-IR cells in a dose-dependent manner. MIC-1 significantly decreased the level of MDA and NO， and significantly increased the level of GSH in C2C12-IR cells. In addition， MIC-1 significantly increased the expression levels of phosphoinositide-dependent protein kinase-1 (PDK1)， p-AKT， and glucose transporter 4 (GLUT4). Conclusion: MIC-1 improves insulin resistance by inhibiting oxidative stress.

Abstract:Activity guided-assisted high-speed counter-current chromatography (HSCCC) was used to separate α-glucosidase inhibitory components from blueberry in this study. Firstly， the active components were enriched in water after being extracted by different solvents. Secondly. the water extract was separated by HSCCC and six components were obtained. The inhibition rate of F4 on α-glucosidase was significantly higher than other components. Then F4 was purified by Sephadex LH-20 dextran gel to obtain high purity component I. Finally， component I was identified as cyanidin-3-O-glucoside (C3G) by UV， FTIR， HPLC-MS and NMR， and its purity was 95.06%. In addition， the interaction between C3G and α-glucosidase was characterized by multispectral scanning and molecular docking. It was found that C3G could spontaneously combine with α-glucosidase through hydrogen bond to form complex. After compounding with C3G， the secondary structure of α-glucosidase changed in varying degrees， in which the α-helix and β-angle decreased， while the β-folding and irregular helix increased. Molecular docking simulation showed that C3G was hydrogen bonded with Leu 313， Ser 157， Tyr 158， Phe 314， Arg 315 and Asp 307， and had hydrophobic interaction with four hydrophobic residues， which maintained the complex structure. The results of this study have important guiding significance for the development of functional foods for treating type 2 diabetes.

Abstract:In order to determine the best process of isolating whey protein， the structure and functional characteristics were studied. The glycosylation reaction was conducted by separating whey protein (WPI) and Artemisia annua gum (ASG). The optimal process parameters of modified WPI were determined by response surface method: time 118 min， temperature 90 ℃， initial reaction pH 12， and the emulsification activity was 0.735 and the emulsification stability was 245.103. Under the best process parameters， glycosylation products were prepared. The results showed that the glycosylated products (WPI-ASG) and the single protein. The emulsion size distribution was similar， the main free amino acids lysine (Lys) and arginine (Arg) were reduced by 23% and 31.1% respectively， the fluorescence intensity decreased， the FTIR-ART spectroscopy showed that the corresponding absorption peak was significantly weakened or enhanced， the lane intensity measured by SDS-PAGE decreased， and the peak temperature and heat enthalpy were increased by the differential scanning meter. Comprehensive analysis shows that WPI-ASG has better emulsibility and thermal stability. The results of this study have certain reference significance for the improvement of isolated whey proteins， the preparation of protein-polysaccharide covalent complexes， the improvement of physical stability， and the development of applied proteins or sugars.

Abstract:In order to explore the interaction between nano-liposome (N-lip) and food protein， N-lip was prepared by the thin film dispersion method. Lactoferrin (Lf) was used as the model protein to evaluate the effects of the nanoliposome/lactoferrin (N-lip/Lf) complex formation under different protein concentrations and dripping methods on the particle size， Zeta-potential and polydispersity coefficient， and the stealth rate (Fs) was used to estimate the degree of binding of N-lip and Lf. The transmission electron microscope was used to compare the morphological changes before and after the action of lactoferrin， and the interaction between Lf and N-lip was analyzed by spectroscopy and X-ray diffraction. The results showed that: when the phospholipid mass concentration was 10.0 mg/mL， the mass ratio of phospholipid to cholesterol was 10∶1， the mass ratio of phospholipid to Tween-80 was 4∶1， and the protein mass concentration was 0.1 mg/mL， the average particle size and the zeta potential of the N-lip/Lf complex formed were (100.80±0.141) nm and (-54.9±2.276) mV， respectivlely， with favourable dispersion. Transmission electron microscope observation showed that Lf formed a light-colored wrapper around the edge of N-lip. The interaction between Lf and N-lip promoted the hydrophobicity of the environment where tryptophan and tyrosine residues in Lf were located， and the content of the alpha-helical structure of Lf increased； Lf could interact with the N-lip phospholipid bilayer membrane through hydrogen bonding， van der Waals force and hydrophobic interaction， adsorb to the surface of the phospholipid membrane and change the polar environment of the N-lip membrane. The research results can provide a theoretical basis for the interaction between liposomes and food proteins and the potential application of the former in the food industry.

Abstract:In this study， starches of three typical crystalline including corn starch (type A)， potato starch (type B) and pea starch (type C) were used as raw materials， and modified by compound-enzymes (branching enzyme， β-amylase) and ultrasonic-compound-enzymes strategies to explore the structures and digestive characteristics of the three kinds of typical crystal starches before and after modifications. The amylose content， branching density， molecular structure and crystal structure of the three kinds of starch before and after modifications were analyzed by means of iodine-blue method， nuclear magnetic resonance hydrogen spectrum， Fourier transformation infrared spectrum and X-ray diffraction， and the mechanisms of the effect after modification on the digestible properties of starches were further explored. After the compound-enzyme treatment， the results suggested decreased amylose content and the relative crystallinity， while the branching density and the degree of molecular order were increased. The hydrolysis index (HI) and glycemic index (GI) of slow digestion starch were significantly increased， and the changes of pea starch were the largest among the three kinds of starches. The above indexes were further improved after the application of ultrasound. The three kinds of starches were transformed into C+V structure with V structure as the main crystal after modifying by ultrasonic-compound-enzymes strategy. Conclusion: Among the three typical crystalline starches， pea starch was the most sensitive to modification by compound-enzymes strategy. The ultrasonic-compound-enzymes strategy can change the structure of starch more efficiently， thus improving its digestibility. The above researches could provide theoretical basis for developing processing technology of functional food with desirable GI.

Abstract:In order to improve the poor strength and deterioration of the unrinsed surimi gel， the effects of three different ionic polysaccharides， including carragenan， konjac gum and chitosan， on the physical properties， low-field NMR， rheology and microscopic imaging of the unrinsed surimi gel of tilapia were analyzed. The results showed that， compared with the blank (47.81)， the maximum whiteness values of different polysaccharides (carrageenan， chitosan， konjac gum) were 93.07， 80.88 and 73.95， indicating that the improvement effect of carrageenan was the best， and the whiteness values of the three polysaccharides were the maximum when the addition amount of all three polysaccharides was 1%. The results of water retention showed that: compared with the blank (88.18%)， the water retention of 1% carrageenan was the highest (92.51%). The T22 relaxation peak area in low-field NMR indicated that the content of unmobile water in carrageenan was higher， indicating that the gel network was more compact and ordered. In terms of texture， carrageenan supplementation significantly increased the hardness of surimi compared with the blank group without polysaccharide (P＜0.05)， the hardness increased by 155.44， 1 168.21 g and 2 252.2 g at 0.5%， 1% and 2%， respectively. The masticability was increased by 93.53， 700.99 and 1 108.22， respectively， and the results showed that the content of polysaccharide ≥1% could significantly improve the texture characteristics of surimi. In terms of gel strength， the gel strength of carrageenan showed great improvement， and compared with the gel strength of the blank group sample (1 585.54 g·mm)， the gel strength of 2% surimi gel reached 3 765.35 g·mm. Rheological properties showed that all three polysaccharides could increase the energy storage modulus (G') of surimi gel at constant temperature. The protein secondary structure showed that the conformation of surimi protein was changed by adding carrageenan and chitosan. Microscopic observation of eosin staining showed that with the increase of polysaccharide content， the region of polysaccharide phase became larger and larger， and the microstructure of surimi gel in the protein phase region of carrageenan added among the three polysaccharides was dense. The electrophoretic map showed that the addition of carrageenan did not change the color of the bands， and it was speculated that polysaccharide played a main role in filling the surimi gel. In conclusion， the addition of carrageenan is more beneficial to promote the formation of gel network and improve the gel quality of tilapia surimi.

Abstract:In this paper， the steady shear and oscillatory shear mode were applied to explore the influence of the solution mass fraction and blending ratio on the viscosity and rheology behaviors for konjac glucomannan/ hydroxypropyl methyl cellulose (KGM/HPMC) system. The results showed that the KGM/HPMC system was a non-Newtonian fluid， and the increase of system mass fraction and KGM content decreased the fluidity of the composite solution and increased its viscosity at the same time. The molecular chains of KGM and HPMC formed a relative compact structure through hydrophobic interaction in solution state， which was stabilized by increasing the system mass fraction and KGM content. For low mass fraction system， more KGM content was favor for the formation of hot-set KGM/HPMC gel， while more HPMC content was beneficial for the formation of hot-set KGM/HPMC gel in high mass fraction system.

Abstract:In order to obtain a large amount of corn glutaminase with biological functions， the recombinant plasmid pPIC9K-TGase was first identified by double enzyme digestion and PCR using molecular biology techniques， then linearized by Sac I， electrotransferred into Pichia pastoris GS115， and its expression was induced by 1% methanol. Results by SDS-PAGE analysis， compared with the control， there was a specific protein band at the molecular weight of about 60 ku， which was the target protein. Then， the yeast expressed TGase was reacted with 0.2% casein solution for 2 hours， and SDS-PAGE showed that casein was polymerized into polymers with different molecular weights， indicating that the expressed protein had a good cross-linking effect on casein. Moreover， the TGase from yeast expressed was added to yogurt， and it was observed by scanning electron microscope that the yogurt network structure with yeast expressed TGase became relatively dense. Conclusion: The yeast expressed glutaminase has the biological activity of crosslinking milk protein.

Abstract:Objective: To study the immunomodulatory and antioxidant effect of Rosa roxburghii & edible fungus fermentation broth(REFB) on immunosuppressive mice. Methods: Immunosuppressed mice models were established by intraperitoneal injection of cyclophosphamide. Mice were randomly divided into 6 groups: normal control， model control， positive control， and low， middle， and high dose (3.9， 7.8， 15.6 mL/kg bw) REFB groups. REFB was gavaged for 30 days， and body weight was recorded daily. At the end of the experiment， the immune organ index was determined， the proliferation of T and B lymphocytes was measured by the CCK-8 method， the differentiation of spleen lymphocytes was detected by flow cytometry， the level of spleen cytokines was determined by ELISA， and the level of antioxidant capacity of the liver and thymus tissues was determined using the antioxidant kit. Results: Compared with the model group， all the REFB groups had significantly higher immune organ index (P<0.05)， increased proliferation rate of T lymphocytes (P<0.05)， and promoted differentiation of spleen lymphocytes (P<0.05). Gavage of REFB could increase the spleen level of IL-4， IL-6， and TNF-α， reduce that of IL-10， while significantly increase the liver and thyme levels of superoxide dismutase (SOD)， catalase (CAT)， glutathione peroxidase (GSH-Px) and reduce that of malondialdehyde (MDA) (P<0.05). Conclusion: REFB could effectively alleviate the inhibitory effect of cyclophosphamide on immune function and enhance antioxidant function in immunosuppressive mice.

Abstract:Objective: The preventive effect of camel milk on acute alcoholic liver injury in mice was analyzed by detecting serum and liver indexes， and the mechanism of metabonomics was explored. Methods: 24 ICR male mice were randomly divided into normal control group (NC)， model group (ET) and camel milk group (ET+CM). The mouse model of acute liver injury was established by gavage of large dose (7.3 g/kg) of alcohol for a short time. The protective effect of camel milk on liver was reflected by measuring serum indexes (ALT， AST， SOD and GSH) and liver indexes (TG and TC). The mechanism of camel milk on liver protection was discussed based on metabonomics. Results: Camel milk significantly inhibited the levels of ALT and AST in serum and TG and TC in liver. Meanwhile， camel milk can increase the contents of SOD and GSH in serum by eliminating reactive oxygen free radicals. Through metabolome analysis， the differential metabolites in ET， NC groups and ET， ET+CM groups were mainly related to lipid metabolism， organic acid metabolism and organic oxygen compounds； 28 metabolites with significant differences were screened and identified in NC， ET and ET+CM groups. Alcohol could reduce the contents of acetylcholine， glycine， linoleic acid and phosphatidylcholine in liver； however， camel milk alleviated the above metabolites. KEGG enrichment analysis of different metabolites showed that they were involved in choline metabolism， glycerol phospholipid metabolism and ABC transporter. Conclusion: Camel milk could alleviate the disorder of lipid metabolism and increase antioxidant capacity induced by acute alcohol exposure， and effectively prevents alcoholic liver injury by regulating choline metabolism， glycerol phospholipid metabolism and ABC transporter in mice.

Abstract:Dry-cured ham possesses many bioactive peptides produced from muscle degradation during the whole process. In order to investigate the antihypertensive activity of bioactive peptides in dry-cured ham， Jinhua ham was chosen to isolate the peptides with measuring their renin regulating effect in vitro as well as the blood pressure regulating capacity in vivo. Known from the results， the Jinhua ham peptides had the suppressing effect on renin under the mass concentration of 10 mg/mL with the inhibition rate of 62.21%. In spontaneously hypertensive rats(SHR)， ham derived peptides were gavaged with the measurements of diastolic and systolic blood pressure. In the treatment of 20 mg/mL peptides， diastolic and systolic blood pressure was significantly decreased compared with control， which showed the similar effect with 5 mg/mL of captopril clinical. However， the suppressing effect of Jinhua ham peptides lasted longer than captopril. In summary， the peptides in Jinhua dry-cured ham had significant antihypertensive activity supplying the potential to carry out the further research on the physiological regulation function of bioactive peptides in dry-cured hams.

Abstract:In order to study the lipid-lowering effect of compound tea， the high-fat mice model was established by high-fat diet. Based on the method of UPLC-MS/MS detection platform， multivariate statistical analysis and self-built database， the difference degree of metabolism group among samples was studied. In this experiment， the normal model group (CK)， high-fat diet group (NK) and compound tea group (DH) were set up， and the Xuezhikang capsule was used as the positive drug group (YK) to compare the effects of compound tea on the metabolism of amino acids in the liver of hyperlipidemic mice. The results showed that a total of 13 amino acid metabolites such as L-homocystine， N-acetylmethionine， D-alanyl-D-alanine， S-adenosylmethionine， L-asparagine and L-tyrosine methyl ester in the liver of mice induced by high-fat diet showed a downward trend， which were significantly enriched in the cysteine and methionine metabolism after the intervention of compound tea. Compared with the YK group， only five of amino acid metabolites such as N-acetylaspartate， N-isovaleric acid and alanine were significantly down-regulated after treatment of Xuezhikang. These fundings indicated that compound tea had a certain regulatory effect on liver amino acid metabolites and pathways in hyperlipidemia mice， which effect was better than the positive drug Xuezhikang. The purpose of this study is to explore the mechanism of reducing lipid of amino acids and their derivatives in compound tea by using metabonomics technology， and to provide some reference for the development and utilization of compound tea.

Abstract:Using salted jellyfish as raw material， the dealuminization effect of slightly acidic electrolytic water (SAEW) on salted jellyfish by soaking was studied in this article. After screening the parameters of soak time， material-to-liquid ratio， and available chlorine concentration by single factor experiments， the response surface model was used to optimize the soaking conditions， and the influence of dealumination treatment on quality changes was evaluated from the perspectives of color difference， texture and microscopic analysis. The results showed that the best dealumination conditions were the available chlorine concentration of 37 mg/L， the soak time of 27 min， and the solid-liquid ratio of 1∶4. Under the conditions， the amount of aluminum removed from jellyfish was 120.17 mg/kg， and the removal rate was 30.41%. The order of the intensity of each factor on dealumination effect was available chlorine concentration > soak time> material-to-liquid ratio. With the increase of soaking time， material-to-liquid ratio and available chlorine concentration， the hardness and chewiness of all the products of test group gradually decreased， the change of elasticity showed a trend of rise first and then decline. After treatment， the L* value and W value of the salted jellyfish were significantly increased. In addition， the results in microstructure images showed that the microstructure of the experimental group and the control group were uniform， and no obvious destruction were observed.

Abstract:On the basis of single factor experiment， the extraction process of Gelidium amansii ethanol extract (GAEE) was optimized by response surface methodology. Then， the GAEE was successively extracted by petroleum ether， ethyl acetate and n-butanol， and the antioxidant and antibacterial activities of different extraction phases were evaluated. The results showed that the optimum extraction conditions were as follows: extraction time was 64 min， ultrasonic power was 350 W， extraction temperature was 55 ℃， ethanol concentration was 60% and solid-liquid ratio was 1∶35. The extraction rate of GAEE was 1.654 g/g， and DPPH radical scavenging rate of GAEE (2 mg/mL) was 58.29% Subsequent experiments proved that the antioxidant and antibacterial activities of different extraction phases were concentration dependent， and the antioxidant and antibacterial activities of ethyl acetate phase were the strongest. IC50 values of ethyl acetate phase against DPPH， ABTS free radicals， and hydroxyl radical were 672.4， 14.1， 599.7 μg/mL respectively. Their minimum inhibitory concentrations(MIC) of ethyl acetate phase against Staphylococcus aureus and Vibrio parahaemolyticus were 156.3， 156.3 μg/mL， and the minimum bactericidal concentrations(MBC) of ethyl acetate phase against Staphylococcus aureus and Vibrio parahaemolyticus were 625， 312.5 μg/mL.

Abstract:In order to evaluate the effect of the soaking process on the applied qualities of rice power， the water absorption and protein and microelement and granularity and damage and microstructure etc of brown rice and rice were evaluated in different soaking time of 0.25， 0.5， 0.75， 1， 2， 3， 4， 5， 6， 7， 8 h. The results showed that the water absorption rate of white rice and brown rice increased rapidly within 1 h and 2 h respectively， and the water absorption rate of brown rice was significantly lower than that of white rice， and the water absorption rate was significantly lower than that of white rice within 2 h. After 2 h， the water absorption rate of brown rice increases slowly， and tends to be stable at 5 h. With the extension of soaking time， more honeycomb structures appeared on the surface of white rice， and the honeycomb became larger. The separation appeared between cell walls， and the structure between starch granules became loose， the contents of protein， manganese， zinc and potassium all showed a decreasing trend. The structure of brown rice did not change obviously with time. The granularity of white rice flour within 0.75 h and brown rice flour within 4 h decreases continuously. The starch loss content of white rice flour decreased with the increase of soaking time， but there was no significant change in brown rice flour. In short， because the outer layer of brown rice was wrapped by the peel， it took a long time for water to enter into the brown rice. The water absorption characteristic of brown rice was slower than white rice. With the extension of soaking time， the structure and nutrition of white rice changed significantly， but that of brown rice flour was not obvious.

Abstract:In the present study， the inhibitory effect of yam extract on heterocyclic amines (HAs) formation of roasted Eleutheronema tetradactylum at a high temperature was investigated. Furthermore， precursors (creatine， creatinine， glucose and free amino acids) of HAs， lipid and protein oxidation， flavor changes are evaluated to determine the inhibitory mechanism of yam extracts on heterocyclic amines formation. These results showed that the addition of yam extracts caused a signification HAs reduction of 59.08% and 47.99% of the Norharman and Harman content， respectively， led IQ， 8-MeIQX from (0.29±0.00) ng/g and (0.75±0.01) ng/g below the detected limitation， compared to the control group. Moreover， the addition of yam extracts had significant effect on the HAs precursors and the flavor of grilled horsefish， there's a certain amount of increase of all the contents of HAs precursors， including creatine， creatinine， glucose， glycine， indicating that the addition of yam extract may hinder the conversion of precursors to HAs. The contents of octyal， 2-butanone， isobutanal， 3-methylbutanal， 2-methylbutanal， heptal， hexal， nonaldehyde and 2，3-dimethylpyrazine and other aldehydes decreased， and the addition of yam extracts significantly reduced the oxidation of fat and protein in the process of roasted Eleutheronema tetradactylum. This research provides a new method to minimize the amount of HAs for the reasonable processing of roasted Eleutheronema tetradactylum， which is helpful to food manufacturers for the production of healthier fish products and may be applicable to various meat systems.

Abstract:Exploring excellent indigenous yeast is of great significance for strengthening the terroir of wine and breaking the situation of foreign commercial yeast monopoly. The fermentation and aroma production characteristics of eleven Chinese indigenous Saccharomyces cerevisiae strains were evaluated in this study. Two indigenous yeasts (60258 and 60268) with high-quality oenological characteristics were obtained and then applied for further pilot fermentation with two different grape varieties (Riesling and Syrah). 60258 could accumulate higher amounts of esters， as it produced 3 times and 1.6 times more acetate esters than commercial yeasts in Riesling and Syrah wine， respectively. It also generated near 2 times ethyl esters than commercial yeasts， which promoted the floral and fruity profiles of wine significantly. 60268 produced more glycerol than commercial yeasts， and it was more suitable for red wine making than white wine. The two indigenous yeasts could be a valuable tool to modulate the volatile profiles of wine and had great application prospect in industrial production.

Abstract:Maillard reaction is one of the main ways to produce the flavor of high-temperature fried food. In this paper， the effects of reducing sugars fructose and glucose on the flavor of fried shrimp were studied. Based on electronic nose， electronic tongue and sensory evaluation， adding trace reducing sugar can significantly improve the flavor quality of fried shrimp， and fructose has more significant promotion effect on taste and volatile flavor than glucose. GC-MS analysis showed that trace reducing sugar could significantly increase the volatile flavor compounds of fried shrimp. 38， 41 and 56 volatile flavor compounds were detected in the control group， the group with trace glucose and the group with trace fructose， respectively. Pyrazines in the control group accounted for 0.76% of the total volatile flavor compounds， while pyrazines in the trace glucose group and fructose group increased to 42.31% and 42.44% respectively. The results showed that there were 8， 17 and 20 volatile compounds with odor activity (OAV) values greater than 1 in the control group， the glucose group and the fructose group， respectively. The key flavor compounds were 2，5-dimethylpyrazine， 3-diethyl-2，5-dimethylpyrazine， methyl 2-methylbutyrate and trimethylamine. Among them， 2，5-dimethylpyrazine had the most significant flavor contribution in the group with trace glucose， while 3-diethyl-2，5-dimethylpyrazine and methyl 2-methylbutyrate were the main flavor components in the group with trace fructose. The results showed that the addition of different reducing sugars could promote the formation of different key flavor compounds in fried Eagle Claw shrimp. Although glucose and fructose were isomers， fructose group was better than glucose in flavor improvement.

Abstract:In order to prepare navel orange whole fruit fermented beverage using the complex probiotic strains of Lactobacillus plantarum and Lactobacillus casei， the Box-Behnken response was used to investigate the fermentation temperature， time and inoculation amount of the beverage， and the fermentation conditions of the beverage were optimized by indexes (viable bacteria count and sensory score). The aroma components of navel orange juice before and after fermentation were analyzed by HSPME-GC-MS. The results showed that the optimal fermentation process of navel orange whole fruit fermented drink was fermentation temperature 34 ℃， time 23 h， inoculation amount 3%， viable bacteria count (8.91±0.11) lg(CFU/mL)， sensory score 84.8 points. Under these conditions， the aroma content of the drink after fermentation was richer. There were 8 kinds of alcohols， 2 kinds of lipids， 5 kinds of ketones， 6 kinds of alkenes， 2 kinds of aldehydes and 4 kinds of other kinds of components with the increase of relative content. The increase of relative content of alcohols and aldehydes was the most， which mainly gave the fermented juice more fruity flavor. Therefore， fermentation is beneficial to improve the flavor of navel orange juice and give it typical flavor.

Abstract:In this paper， the inhibitory enzymatic browning effects and the inhibition kinetics of polyphenol oxidase of Phyllanthus emblica by oxyresveratrol combined with ascorbic acid were studied to explore their synergistic inhibition mechanism of browning enzyme. The results showed that 0.02% oxyresveratrol， 0.15% ascorbic acid， and 0.02% oxyresveratrol + 0.15% ascorbic acid could reduce the enzymatic browning of P. emblica and had a good inhibitory effect on the activities of polyphenol oxidase (PPO)， peroxidase (POD) and phenylalanine ammonia lyase (PAL). The treatment of 0.02% oxyresveratrol combined with 0.15% ascorbic acid had stronger inhibitory activities on enzymatic browning and PPO， POD and PAL of P. emblica than that of oxyresveratrol alone. The results of enzyme inhibition kinetics showed that the IC50 of oxyresveratrol on PPO was (3.300 ± 0.010) μmol/L， its inhibition mechanism was reversible mixed inhibition， while the IC50 of oxyresveratrol combined with ascorbic acid (1∶7) was (1.600 ± 0.020) μmol/L， their inhibition mechanism was reversible competitive inhibition， and this cooperative use led to the change of inhibition mode. The inhibition constant KI of oxyresveratrol on PPO was 0.904 μmol/L， whereas its inhibition constant KIS of the complex formed by PPO and substrate was 14.285 μmol/L. Furthermore， the inhibition constant KI of oxyresveratrol combined with ascorbic acid (1∶7) on PPO was 0.840 μmol/L. Lower than that used oxyresveratrol alone， the inhibition of PPO was strengthened by oxyresveratrol combined with treatment ascorbic acid.

Abstract:Chitosan is a natural polysaccharide with multiple biological activities， which can participate in various physiological processes in organisms. The present study investigated the effects of 2% chitosan coating on the storage and nutritional quality， membrane permeability， energy metabolism in fertile orange fruit during storage at 25 ℃. The results revealed that chitosan effectively delayed the decrease of soluble solids and total titratable acid and the increase of weight loss and ratio of soluble solids to acidity， and inhibited the decrease of carotenoids， ascorbic acid， total phenol and flavonoid contents in fertile orange fruit. Further investigation presented that chitosan significantly inhibit the increase of membrane permeability， which is reflected in the lower relative electrical conductivity and malondialdehyde content in fruit tissues. In addition， chitosan maintained a higher energy status， as demonstrated by enhancing adenosine triphosphate content and energy charge， which could be attributed to improve the activities of H+-ATPase， Ca2+-ATPase， succinate dehydrogenase， cytochrome C oxidase during storage. In summary， chitosan can effectively maintain the storage and nutritional quality and delay senescence of postharvest fertile orange fruit by regulating membrane permeability and energy metabolism.

Abstract:Browning is an important factor contributing to the quality deterioration of fresh-cut lotus roots. In this study， 150 μL/L ethanol fumigation for 2 h was employed to investigate the effects of ethanol on the enzymatic browning and reactive oxygen metabolism of fresh-cut lotus root slices. The results showed that after storage at 10 ℃ for 12 d， the browning degree and L* value of fresh-cut lotus root slices decreased by 6.49% and increased by 21.44%， respectively， after ethanol treatment， compared with the control group. Ethanol treatment also could suppress the synthesis and oxidation of phenols in fresh-cut lotus roots by inhibiting phenylalanine deaminase and polyphenol oxidase activities. By the end of storage， the soluble quinone content of the control group was 1.15 folds as that of the ethanol-treated group. In addition， ethanol treatment could effectively maintain catalase and peroxidase activities and ascorbic acid content. After 12 d of storage， the O₂-· production rate and H2O₂ level in fresh-cut lotus roots after ethanol treatment were 87.69% and 79.17% of those in the control group， respectively. In conclusion， ethanol fumigation treatment may delay the occurrence of browning in fresh-cut lotus roots by inhibiting phenolic metabolism and increasing antioxidant ability.

Abstract:The fruity-flavored yeast SSF12 was used as the research object and another strain NGF6 with poor fruity flavor was used as the control to study their transcriptomic differences in the process of wine fermentation. Combined with the physical and chemical indexes， aroma substances content and sensory characteristics of fermentation broth， the metabolic characteristics and related regulated mechanism of aroma substances of fruity yeast were revealed. Results showed that SSF12 had higher sugar utilization and fermentation degree. The contents of esters， alcohols and terpenes in the fermentation broth of SSF12 were higher than that of NGF6， while the contents of aldehydes and fatty acids were lower than NGF6. Meanwhile， the fruity sensory characteristics of the fermentation broth of SSF12 were significantly better than that of NGF6. Transcriptomic analysis showed that there were 434 genes differentially expressed in SSF12 compared with NGF6 (including 290 up-regulated genes and 144 down-regulated genes). KEGG analysis showed that SSF12 had more up-regulated genes in carbohydrate (especially sugars， higher alcohols and esters) metabolism and nucleic acid metabolism， thus might be more prominent in these pathways. NGF6 had more up-regulated genes in pathways of acetaldehyde synthesis， fatty acid synthesis and some amino acid metabolism. The differentially expressed genes such as ADH2， ADH6， ALD3， and ATF2 were closely related to aroma substances metabolism. So they can be used as candidate genes for wine aroma improvement. Results of this study might provide a reference for the breeding and strain improvement of fruity-flavored yeasts.

Abstract:A simple method for accurate identification of Baijiu was developed without qualitative and quantitative determination of volatile components. A total of 10 kinds of Baijiu with two flavor types were selected， and each of them has 2 samples from different blending batches. After directly headspace sample preparation， gas chromatography-ion mobility spectrometry (GC-IMS) was used to obtain the visualized fingerprints， and further extract the main features of Baijiu to establish Fisher linear discriminant models. A total of 134 volatile components were detected in the samples. The fingerprints can directly reflect the content difference of trace volatile components and the batch stability of blending. Under the premise of not fully analyzing and quantifying all components， stepwise regression analysis is used to optimize the three Fisher linear discriminant models which are respectively based on all 134 volatile components， 39 characteristic components selected by correlation analysis， and the 6 principal components obtained from principal component analysis. For the optimized correlation analysis model (the component features are reduced to 21) and the principal component analysis model， the classification accuracy rates and leave-one-out cross validation classification accuracy rates for the training set are 100%， and the discrimination accuracy rates for the test set are both 95%. The optimized Fisher linear discriminant model based on all the features has the best result， and 24 component features are extracted. The model's classification accuracy rate of the training set is 100%， the leave-one-out method cross-validation classification accuracy rate is 100%， and the prediction accuracy rate of the Baijiu samples in the test set reaches 100%. The GC-IMS is significant for the quality control， market supervision and the origin protection of Baijiu， and it can accurately identify Baijiu combining with pattern recognition.

Abstract:Hongqu is a product fermented by Monascus. To improve the quality of Hongqu， isolation and identification of high-quality Monascus strains are required， but the current identification scheme of Monascus and the screening strategy of high-quality strains are still insufficient. For this purpose， based on the construction of the Monascus strain library， the results of morphological identification and molecular biological identification of Monascus were compared， and a reasonable identification scheme was proposed through correlation analysis； the yield of pigment and citrinin were determined for strains with different morphological types， and high-quality Monascus strains were screened by yield conversion method. Result: Multiple Monascus strains with different morphologies may exist in a single Hong Qu， and a Monascus strain bank was constructed containing 45 different morphological typing isolates for a total of 148 Monascus spp. with 44 Hongqu samples as the source of strains； Morphological analysis indicated that most Monascus spp. were similar to M. purpureus， M. aurantiacus， and M. pilosus， while ITS rDNA sequencing and 18S rDNA sequencing easily matched unknown Monascus spp. to M. purpureus， M. pilosus， and M. ruber； correlation analysis indicated that ITS rDNA sequencing more closely resembled the morphological analysis results than 18S rDNA sequencing； due to the larger variety and number of reference strains in gene databases for ITS rDNA sequencing， ITS rDNA sequencing result is recommended when the results are different among multiple identification methods； at last， Monascus MZT27 with high-yield pigment (83.3 U/mL) and low-yield citrinin (81.5 ng/mL) was screened by referring to the three indexes of pigment yield， citrinin yield， and the ratio of citrinin yield to pigment yield， and Monascus MZT39 with high-yield yellow pigment (accounted for 70.06%) was screened by the ratio of yellow to total pigment. This study contributes to the exploitation of Monascus germplasm and the promotion of the quality of Hongqu.

Abstract:Fu brick tea is a kind of dark tea fermented with microorganisms. The fungal potpourri is the brick tea unique aroma quality， formed with fermentation is directly related to fungi flora succession. To reveal the characteristics of fungi flora of Fu brick tea fermentation succession law， the dark tea and white tea were made from Yabukita tea Camellia sinensis (L.) O. Ktze from Shenlin Tea Industry Development Co.， Ltd.， Luoshan County， Xinyang City， Henan Province. After that， the Fu brick tea and white tea brick are respectively made from flowers in the same place. Microbiome amplifiers ITS (Internally Transcribed Spacer) were used to analyze the succession law of fungus with fermentation characteristics of Fu brick tea. The results showed that: 1) There was no significant difference in the fungal diversity of different tea species during the fermentation process， but the difference was caused by the different variation rules of characteristic fungal abundance. 2) The piles-fermentation changes the flora structure and microbial growth environment of Fu brick tea， which directly leads to the significant difference in the flora succession of fermentation fungi between Fu brick tea and other types of tea. 3) Succession law of fungus flora with fermentation characteristics of Fu brick tea: In the early stage of Fu brick tea blossoming， Aspergillus_niger， Aspergillus_restrictus， Aspergillus_sydowii， Penicillium_steckii， Penicillium_brocae， Debaryomyces_hansenii with higher abundance affected by piles-fermentation， showed abundance peak on the 6th day of fermentation. After that， on the 9th day of fermentation， the abundance peaks of Eurotium， Meyerozyma_caribbica， Wickerhamomyces_anomalus， and other fungi appeared. Aspergillus_niger， Debaryomyces_hansenii， Aspergillus_restrictus maintains abundance. On the 12th day of fermentation， Aspergillus_pseudoglaucus had its peak abundance， Aspergillus_niger continued to maintain its abundance. By the end of fermentation day 22， Eurotium was finally the dominant species.

Abstract:To explore the differences of metabolites in the mature fruits of yellow raspberry and red raspberry， nontargeted LC-MS metabolomics analysis was carried out. A total of 708 (98 known) significantly differentially expressed metabolites were detected in the positive ion mode. In the negative ion mode， there were 780(45 known) significantly differentially expressed metabolites. Through the metabolic enrichment analysis of KEGG database， 1 566 differentially expressed metabolites in red raspberry and yellow raspberry fruits are enriched in four categories: metabolism， genetic information processing， environmental information processing and human diseases. These differentially expressed metabolites were enriched in 66 pathways， and the metabolic pathways (ko01100) enriched the most differential metabolites (34 species). In addition， delphinidin 3-glucoside， (s)-abscisic acid， hydrocinnamic acid and hesperetin in yellow raspberry fruits were -1.496， -1.632， -1.527 and -0.477-fold lower than those in red raspberry fruits， respectively. Protochlorophyllide was up-regulated more than 10 times in yellow raspberry fruit. The results provide theoretical basis for the development and utilization of specific compounds in different raspberry fruits.

Abstract:Purpose: In order to make a comprehensive evaluation of the texture characteristics of frozen instant sea cucumbers. Method: Used texture analyzer (texture profile， shear force and stress relaxation mode) detection and sensory evaluation to characterize the texture of frozen instant sea cucumbers after four thawing methods. Analyzed the correlation between instrument detection indexes， instrument detection indexes and sensory evaluation indexes， and perform principal component analysis on instrument detection indexes. Results: The instrument detection indexes and sensory evaluation indexes of the four groups of samples were significant different (P＜0.05). In addition to cohesiveness and elasticity， longitudinal shear force， coefficient of viscosity η. There was a high correlation among the 9 instrument detection indexes (r≥0.800). Meanwhile， there was a certain correlation between instrument detection indexes and sensory evaluation indexes (r=0.577-0.994). The principal component analysis found that group refrigerated thawing with the highest total sensory evaluation approached the positive direction of principal components 1 and 2， and could be better explained by TPA cohesiveness， hardness， transverse shear force and elastic modulus E1. Conclusion: The indexes of the texture properties of frozen instant sea cucumbers have a good correlation. This study provides a certain theoretical reference for the texture evaluation of frozen instant sea cucumbers.

Abstract:In order to explore the bacterial community structure and pathogenic bacteria composition in different pickles in AnNin County， Yunnan Province. High-throughput sequencing technology and traditional separation and culture methods were used to analyze the bacterial community structure and pathogenic bacteria composition of nine pickles samples. The experimental results showed that the bacterial community structure in the nine pickles samples was similar， but the relative abundance was quite different. Among them， Lactobacillus， Bacillus and Staphylococcus are the main genera of dominant bacteria， which play an important role in the formation of pickles flavor substances. In addition， 16S rDNA sequencing results of the isolated and cultured food-borne pathogens in pickles showed that some of the pathogens were detected in the nine pickles samples， mainly Listeria monocytogenes， Bacillus cereus， and Escherichia coli， Staphylococcus aureus and Salmonella. In conclusion， pickles in the market are prone to pathogenic bacteria， which may pose a certain safety risk.

Abstract:In order to explore the quality difference of the pickled and dried mustard and， the physicochemical properties， free amino acids， and volatile substances of nine kinds of the pickled and dried mustard were analyzed using automatic amino acid analyzer and gas phase ion migration spectrum， respectively， and the comprehensive evaluation was conducted by cluster analysis and principal component analysis. The results showed that the pickled and dried mustard had significant differences in water， crude protein， total sugar and salt content and other physicochemical properties. The correlation between amino acids was basically positive， with most of the correlation coefficients greater than 0.4， indicating a significant positive correlation， and half of the correlation coefficients greater than 0.8. Among them， Thr and Tyr had the strongest correlation， with a correlation coefficient of 0.982. In addition， the principal component analysis of free amino acids in the pickled and dried was carried out. Two principal components were extracted from 17 amino acid indexes， and the cumulative contribution rate reached 90%， which basically reflected most of the information of the original indexes. The comprehensive score of free amino acids in pruned vegetables in Sichuan， Hubei， Jiangxi and Anhui provinces was higher than the mean value， and the result of cluster analysis verified the conclusion. Finally， based on gas-chromatography-ion mobility spectrometry technology， the volatile fingerprints of the pickled and dried mustard were established to analyze the differences between nine kinds of the pickled and dried mustard. A total of 123 volatile compounds were identified using NIST database and IMS migration time database， mainly including esters， aldehydes， alcohols， acids and other substances. The compounds of nine kinds of pickled and dried mustard were different in proportion， which might be related to their different processing techniques. Among them， the relative contents of eight kinds of brassica aldehydes accounted for more than 30% of the total volatile substances， which may have important contributions to the overall flavor of dried vegetables.

Abstract:In this paper， it reported an acetylcholinesterase(AChE) and choline oxidase (COD) were immobilized and co-modified on the bare gold electrode surface by electrodeposition to construct a novel immobilized enzyme biosensor. The morphology of immobilized enzyme was characterized by electron microscope. The results showed that the comodification layers of immobilized acetylcholinesterase and immobilized acetylcholinesterase in immobilized enzyme biosensor were 2 layers and the number of modification cycles was 35. When the concentration of acetylcholine chloride substrate is 2 mmol/L and pH value is 7.8， the biosensor can recognize the organic phosphorus pesticide signal and has a good detection performance， with a good sensor current response at the organic phosphorus pesticide concentration of 10-9 to 10-7 mg/L. The working curve equation is y=0.0468x + 1.2124 (R2=0.9985)， and the lowest detection limit is 1.15×10-11 mg/L (S/N=3). This research method will provide a new research direction for the rapid detection of organophosphorus pesticides in the field.

Abstract:Trichlorfon (TCF) is a highly effective and low-toxic pesticide. However， it can be converted into dichlorvos under alkaline environment， which increases toxicity. The detection of TCF is of great research importance. A flexible gold nanoplates (AuNTs)/tape based SERS substrates was fabricated. The target pesticide was extracted with adhesive tape from sample surface and then covered with AuNTs solution for SERS measurement. The AuNTs/tape SERS substrates was first assessed with good reproducibility and sensitivity using Nile Blue A (NBA) as Raman signal molecule. The intensity of TCF's Raman characteristic peak at 757 cm-1 showed a good linear correlation with the concentration of TCF solution ranging from 1 μg/mL to 10 μg/mL (y = 226.370x + 193.861， R2 = 0.9960). The LOD was calculated to be 0.781 μg/mL. The proposal of AuNTs/tape SERS substrates provide a novel method for pesticide detection.

Abstract:Based on enhanced matrix removal lipid column (Captiva EMR-Lipid) purified， a method was developed for determination of 42 kinds of triazine， amide and sulfonylurea herbicides residues in shellfish by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). After optimizing the pretreatment and chromatographic conditions， acetonitrile， Captiva EMR-Lipid column were used as the extraction solvents and purification agents， respectively. The separation of 42 analytes was performed on a Shim-pack GIST C18-AQ column (100 mm × 2.1 mm， 1.9 μm) with gradient elution. The MS/MS detection was performed with electrospray ionization in positive ion mode and multiple reaction monitoring mode. The 42 analytes showed great linear relationships in the range of 0.2-20 μg/L with correlation coefficients (R2) all above 0.992. The limits of detection (LODs) were 0.2-0.4 μg/kg and the limits of quantitation (LOQs) were 0.5-1.0 μg/kg. The average recoveries of analytes varied from 61.0% to 110.3%， and the relative standard deviations (RSDs) were between 0.1% and 17.4%. Using the established determination method， 23 shellfish samples were detected， and 5 kinds of herbicides residues were detected. The method was simple， rapid， high accurate and sensitive， which was suitable for the simultaneous determination of 42 kinds of herbicides residues in shellfish.

Abstract:Probiotics are live microorganisms that are beneficial to human health. Because the bacteria are highly sensitive to the external environment， problems such as low survival rate or poor biological activity are prone to occur during production， storage and use， which greatly reduces the probiotic effect of probiotics. The embedding technology can protect the probiotics from the environment and related factors to a certain extent， and has a good effect on the probiotics against external adverse conditions. In recent years， the rapid development of probiotics embedding technology has provided effective strategies for the efficient protection of probiotics. This study reviews four advanced probiotic embedding technologies: emulsification/ internal gelation method， Pickering emulsification method， complex coacervation method and multi-layer embedding method， and summarizes the technology introduction， principle， advantages and disadvantages. Then the application of probiotics embedding technology in the food field is outlined， including the changes in the number of viable bacteria in the gastrointestinal tract and the impact on the sensory characteristics of food. Finally， the research direction and development prospects of probiotics embedding technology are prospected.

Abstract:Plant-based nutritional and healthy foods have been the future directions in future food industry as well as an important demand of national healthy diet. To develop plant-based nutritional and healthy foods， it is necessary to understand the formation and evolution of the cross-scale structure of food soft matter during processing and the related influence on functions and properties. Based on elucidating the cross-scale structural characteristics of the nutritional and healthy food， the creation pathway and the regulation mechanism of texture characteristics of plant-based nutritional and healthy food products were further analyzed. According to the principle and application of extrusion processing technology， the research advances of the effect on the starch/ plant protein complexes during extrusion processing were demonstrated， which included the formation and evolution rules of cross-scale structure of the complexes and their texture characteristics. The important basic scientific problems and the future outlooks in the exploration of related research areas were also pointed out， which were aimed to provide guideline for improving the quality of plant-based nutritional and healthy foods and promoting the food industry development in a comprehensive manner.

Abstract:Bacterial food poisoning is a food safety problem， which is mainly caused by food borne pathogens. In the stage of food processing and storage， bacteria have evolved complex regulatory mechanisms to adapt to the harsh living environment. For example， it can improve the survival rate by changing the expression level of its own genes. Non coding small molecule RNA (sRNA)， which is abundant in bacteria， plays an important role in regulation. SRNA can promote or inhibit protein synthesis in a variety of ways， which is closely related to the expression of bacterial physiological mechanisms， environmental stress tolerance， etc. Bacteria that induce sRNA transcription and regulate it due to environmental changes will have significant changes in physiology and resistance. It may lead to enhanced resistance of bacteria， which is difficult to be eliminated. At the same time， it will also increase its own toxicity and threaten human life and health. This article mainly reviewed the influence of sRNA on the pathogenicity of foodborne pathogens， and the regulation mode under stress due to environmental change， revealing the role of sRNA in biological adaptive evolution and life activities.

Abstract:At present， the market supervision department actively promoted the implementation of "territorial management responsibility" and "enterprise's main body responsibility" for food safety， and strictly prevented and controlled food safety risks. Therefore， in order to guide and supervise food enterprises to apply scientific and effective methods to implement the main body responsibility of food safety， learn from and transform international food safety standards， and comprehensively promote the application of food safety prevention and control measures based on hazard analysis and critical control point (HACCP) principle is imperative. This article systematically analyzes the application of HACCP system， investigates the measures taken by local food regulatory departments to promote the application of HACCP and adopt HACCP related certification， concludes the benefits of applying HACCP principles to prevent and control food safety risks， as well as summarizes the problems and challenges in the application of HACCP. In addition， based on the actual situation of China， this paper puts forward relevant suggestions on the development of HACCP from four aspects: standard revision， talent training， scientific and technological support， and innovation of supervision mode. To provide theoretical support for improving the scientific and systematization of food safety risk screening and prevention and control of food producers and operators， and improving the government regulatory governance mechanism and system construction.