Abstract:The process and recovery of allogeneic hematopoietic stem cell transplantation are closely related to the immune system. Current research shows that in addition to the immune organs such as the spleen， thymus， and bone marrow， tissues such as the small intestine and liver also play an important role in immune regulation. The interaction of the intestine-liver axis， liver-spleen axis and other organs in immune regulation supports a better view to understand the mechanism of disease development and to develop immune related therapy methods. Our team applied the dual-protein to the clinical nutrition intervention of allogeneic hematopoietic stem cell transplantation， and found that the dual-protein can significantly promote immune reconstruction， shorten the average transplantation time， and conduct a preliminary exploration of its mechanism. In this paper， a review about the immune interaction mechanism among intestine， liver and spleen is performed， which followed by a new concept of intestine-liver-spleen axis （ILS Axis） and its mechanism. A hypothesis is proposed that dual-protein promotes hematopoietic and immune reconstruction， and therefore accelerates patient recovery via intestine-liver-spleen axis based on the results of dual-protein clinical trials and animal experiments.

Abstract:Purpose： To explore the in vitro antioxidant activity of high-nucleotide yeast hydrolysate. Methodology： The scavenging activity of diphenyl bitter acyl radical（DPPH）， hydroxyl free radical as well as the total reducing power were measured by chemical method. The oxidative stress model of the HepG2 cell induced by free fatty acid （FFA）was established. The effects of high nucleotide yeast hydrolysate on HepG2 cells were detected by thiazolyl blue tetrazolium bromide（MTT）. And the changes of reactive oxygen in the HepG2 cells were measured by fluorescent probe method. Commercial kits were used to detected the activities of intracellular oxidative damage markers such as malondialdehyde （MDA）， superoxide dismutase （SOD） and glutathione peroxidase （GSH-PX）. Real-time quantitative PCR was used to detect mRNA expression levels of keap1， Nrf2， HO-1 and NQO-1. The excitation and transposition of Nrf2 was dected by western-blot. Conclusion： 5~50 mg/mL high nucleotide yeast hydrolysate could scavenge oxygen free radicals in vitro in amass concentration-independt manner and had significant antioxidant capacity. 500-1 000 μg/mL high nucleotide yeast hydrolysate could significantly decrease the content of malonaldehyde （MDA） in the cells as well as the level of reactive oxygen species（ROS）； additionally and increase the activities of superoxide dismutase （SOD） and glutathione peroxidase （GSH-PX）. The expression mRNA levels of the antioxidant enzyme genes NQO1， Nrf2 and HO-1 were also significantly increased， and the expression mRNA level of keap1 was significantly decreased. High nucleotide yeast hydrolysate could increase the protein content in the endonuclear of HepG2 and decrease the protein content of Nrf2 in the endochylema， and this results could futher clarified that high nucleotide yeast hydrolysate could reduce FFA-induced HepG2 oxidation by activating the Nrf2 pathway injury effect.

Abstract:AHLs are a kind of signal molecules that mediate quorum sensing of gram-negative bacteria. Screening microorganisms with degradative activity on AHLs from nature as a quorum sensing inhibitor is a new strategy for controlling pathogenic bacteria. 56 strains of degrading Aeromonas hydrophila quorum-sensing AHLs signaling molecules were rapidly screened out from 156 strains of lactic acid bacteria that isolated from traditional fermented foods and marine fish intestines using a 96-well plate method. The initial screening rate was 35.90%. 56 strains of lactic acid bacteria screened out 12 strains with strong degradation activity by agar diffusion method. The degradation activity of strain YP 4-1-1 derived from the intestine of marine fish gingiva was close to 100%. Analysis by GC-MS showed that the activity of the strain YP 4-1-1 degrading Aeromonas hydrophila C4-HSL and C6-HSL was 98.31% and 81.06%， respectively. The physiological and biochemical reactions and 16S rRNA sequence analysis confirmed that strain YP 4-1-1 was Lactobacillus sakei. Further studies showed that the quorum quenching enzyme activity of strain YP 4-1-1 is present in the soluble fraction of the crude cell extract， and may be an AHLs-acyltransferase or oxidoreductase. The MICs of YP 4-1-1 crude extracts against Chromobacterium violaceum CV026 and Aeromonas hydrophila were 2.0 mg/mL and 4.0 mg/mL， and three different sub-MICs（1/4 MIC， 1/2 MIC and 3/4 MIC） dose-dependent degradation of the purple pigment. In vitro co-culture experiments， strain YP 4-1-1 attenuated the expression of virulence factors such as hemolysin， DNase and lipase of Aeromonas hydrophila， and had inhibitory activity on quorum-sensing clustering and migration. In this paper， strains with degrading activity against gram-negative bacteria AHLs signal molecules are obtained from lactic acid bacteria in the natural environment， which lays the theoretical and application foundation for the development of lactic acid bacteria biological agents that control quorum sensing.

Abstract:This article aimed to investigate the stability and the in vitro digestion characteristics of the oil-in-water emulsions stabilized by casein gel particles， comparing with sodium caseinate and tween 20. The droplet size， zeta potential and stability of oil-in-water emulsions were measured using Mastersizer， Zetasizer and Turbiscan lab， respectively. The digestion characteristics of the emulsions stabilized by casein gel particles were investigated by in vitro simulated digestion， making comparison to sodium caseinate and tween 20. The results showed that the Turbiscan stability index of oil-in-water emulsions stabilized by casein gel particles was 0.71 ± 0.09， which was significantly lower than the emulsions stabilized by sodium caseinate （1.43 ± 0.09） and tween 20 （1.62 ± 0.15）， indicating that the stability of the casein gel particles stabilized emulsions was best. This may be attributed to strong steric hindrance and electrostatic repulsion formed by casein gel particles with complete structure on the oil-water interface. The results of in vitro digestion showed that the release of the free fatty acid of the emulsions stabilized by casein gel particles， sodium caseinate and tween 20 was（86.13 ± 3.91）%， （86.79 ± 3.61）% and （91.62 ± 1.31）%， respectively. There was no significant difference in lipolysis among three emulsions， indicating that casein gel particles would not impede lipid digestion of the emulsions. The type of emulsifiers had effects on the initial rate of lipid digestion， but no effects on the final lipid digestion. In conclusion， casein gel particles can improve the stability of oil-in-water emulsions and have no effect on the digestion.

Abstract:The polysaccharide of soybean hull （SHP） was a high molecular weight acidic polysaccharide isolated and purified from soybean hull. The atomic force microscopy （AFM） was used to observe the apparent morphology on the surface of solution-mica for exploring the advanced conformational characteristics of polysaccharides， and verified by rheology. The results showed that the mass concentration and ionic strength significantly affected the AFM imaging of SHP， and the images of molecular aggregation behavior of different morphological polysaccharides were obtained. The interaction between polysaccharides was weakened as the concentration decreased. The conformation of polysaccharides gradually dispersed from densely packed strip-like structures into branched， single- and double-stranded structures in aqueous solution， and a cross-linked gel network structure into a short spiral-like structure in 0.5 mol/L KCl solution. The effects of ionic strength on SHP were reflected in the tightness of polysaccharide， and the conformation transformed from a stretched flexible long chain to a helical rigid short chain. By static rheological measurement of SHP solution， it was verified that the addition of KCl led to the cross-linking of polysaccharides chains to form a network structure， and the solution system gradually changed from a fluid state to a weak gel state.

Abstract:This study aims to study the enzymatic characterization of extracellular laminarases from Microbulbifer sp. ALW1 and the antioxidant activity of the enzymatic hydrolysates. The results showed that the optimum temperature of laminarinase was 45 ℃ using laminarin as the substrate， and the enzyme activity was stable under 35 ℃. The optimum pH of laminarinase was 5.5， and the enzymatic activity was stable at pH between 6.0 and 8.0. Na+ could promote the enzyme activity， but K+， Fe2+， Cu2+， Co2+， Mn2+， Ba2+， Cd2+ and Zn2+ could inhibit the laminarinase activity to some extent. The enzymatic hydrolysates had reducing ability and scavenging power on ABTS and hydroxyl radicals. The half inhibitory concentration （IC50） values of scavenging activity towards ABTS and hydroxyl radicals were 15.2 mg/mL and 1.7 mg/mL， respectively. These results showed that the enzymatic hydrolysates had antioxidant activity.

Abstract:In order to investigate the effects of protein opening methods on the antigenicity and enzymatic cross-linking of whey protein， heating or cysteine treatment was used to open the molecular structure of whey protein. The modified whey protein was subjected to transglutaminase （TGase） cross-linking， and the molecular weight of the modified cross-linked product and the direct TGase cross-linked product was analyzed by polyacrylamide gel electrophoresis （SDS-PAGE）. The antigenicity of whey protein was determined by an indirect competitive enzyme-linked immunosorbent assay and the hydrophobicity of whey proteins and their modified products was determined. The experimental results showed that the intrinsic fluorescence and surface hydrophobicity of the heat-treated whey protein modified product were higher than the cysteine modified product. From the results of SDS-PAGE， it was found that the cysteine-modified whey protein were more than the cross-linked product obtained by heat modification. The results of antigenic analysis showed that the heat treatment reduced the antigen content in whey protein by about 20%， and the cysteine modification reduced the antigen content in whey protein by more than 30%. The results showed that cysteine modification could significantly reduce the antigenicity of whey protein more than heat treatment.

Abstract:The objective of this research was to study the effect of oxidization of malondialdehyde which was selected as a representative of reactive aldehydes produced in the process of polyunsaturated fatty acids lipid peroxidation catalyzed by lipoxygenase on the surface properties of walnut protein. Increasing extent of oxidation resulted in gradual carbonyl group generation and carbonyl content of walnut protein were increased from 3.12 nmol/mg to 20.61 nmol/mg. With the degree of oxidization was increased， the particle size of walnut protein was deviated， the relative molecular weight of protein first decreases and then increases and surface tension of walnut protein showed a trend of decrease first and then increase， as well as， the results of absolute value of Zeta potential， surface hydrophobicity， foaming capacity and foaming stability showed the trend of increase first and then decrease. When the concentration of malondialdehyde was to 0.1 mmol/L， the value surface tension of walnut protein reached the minimum， which was 55.64 mN/m， respectively； and the absolute value of Zeta potential， surface hydrophobicity， foaming capacity and foaming stability reached the maximum value， which were 10.38 mV， 476， 21.43% and 17.80%， respectively. Experimental results showed that the molecular structure and interface properties of walnut protein were changed with the oxidation of protein by malondialdehyde， and the interface properties of walnut protein could been improve at low degree of oxidation.

Abstract:Based on the establishment of the ulcerative colitis mice model induced by dextran sulphate sodium （DSS）， this study explored the protective effect of antimicrobial peptide LL-37 on the intestinal mucosal barrier of mice. Forty-eight male C57BL/6 mice were randomly divided into four groups： control group（drinking normal water）， DSS group （drinking 3% DSS water）， DL group （drinking 3% DSS water and administrating LL-37 by intraperitoneal injection） and LL group （administrating LL-37 by intraperitoneal injection）. The experiment lasted for 8 days， during which the disease activity index of mice was evaluated. Immunohistochemistry was used to analyze the degree of inflammatory infiltration of immune cells. Intestinal permeability was detected by ELISA and Ussing chamber. The secretion of inflammatory cytokines was analyzed by ELISA. Real time PCR was used to analyze the expression level of tight junction proteins in colon. The results showed that LL-37 （5 mg/kg·d） could obviously alleviate colitis symptoms such as weight loss， diarrhea and intestinal bleeding in mice， reduce disease activity index of mice. At the same time， LL-37 significantly improved the colonic morphology destruction， inflammatory cell infiltration， and the secretion of inflammatory cytokines TNF-α， IL-1β and IL-6 in serum of mice with colitis （P<0.05）， LL-37 also alleviated the decreased mRNA expression level of the three tight junction proteins in colon （P<0.05） and increased permeability （P<0.05）. These results revealed that LL-37 may alleviate the increase of intestinal mucosa permeability in mice with colitis by reducing the secretion of inflammatory cytokines in colon tissue and enhancing the expression of tight junction proteins， so as to realize the protective effect on the intestinal mucosa barrier in mice.

Abstract:Human milk fat provides 45%-60% of energy for infants. However， due to the difference in fat structure and content， infant formula milk based on cow’s milk and other vegetable oils has a fat digestion and absorption rate that is 20%-25% lower than that of human milk. Thus， the preparation of alternative lipids similar to the structure and composition of breast milk fat is a research hotspot in the field. This article selected Tibet yak ghee with high similarity to human milk fat as the main raw material， fatty acid ethyl ester as the acyl donor， catalyzed by immobilized lipase RM IM， and then other factors of water activity， sunstrates ratio， reaction time and temperature was optimized by response surface methodology. The optimum reaction conditions were obtained： Tibet yak ghee， sunflower oil ethyl ester and oleic ethyl ester which the molar ratio of was 2.13 ∶ 1 ∶ 1 was catalyzed with 10% RMIM （water activity 0.61） at 68 ℃. In the structured lipids， the content of total linoleic acid and palmitic acid sn-2 of final product in model validation actually were 17.59% and 56.40%， which is in consistent with the predicted value and can be used as another source of breast milk fat substitute. Our results provided new possibilities for the synthesis of human milk fat substitute （HMFS）.

Abstract:This experiment used two kinds enzymes （papain and pancreatin） to hydrolyze corn gluten meal for preparing corn anti-alcoholism peptides， the single factor experiment was aimed to explore the influence of different liquid-to-material， the quantity of enzyme， bi-enzyme papain / pancreatin and reaction time during the enzymolysis on the protein recovery ratio and the activation ratio of ADH of corn anti-alcoholism peptides. The optimum technology conditions were as follows： the liquid-to-material ratio was 10 ∶ 1， the quantity of enzyme was 2%， the bi-enzyme papain/ pancreatin was 1 ∶ 1， reaction time was 8 h. Under such condition， the protein recovery ratio was 69.89% and the ADH activation ratio was 65.72%. Then corn anti-alcoholism peptides were separated and enriched by ethanol with various concentrations， and alcohol-sinking component with 80% ethanol had the highest ADH activation ratio（75.08%）. Sephadex G-15 was used for the second step separation and enrichment of the ethanol precipitation component of 80% ethanol， the four peaks were eluted， the overall recovery ratio was 84.52%. the percentage points of 4 classes were as followed： 24.36%， 47.79%， 3.25%， 9.12%， respectively. From the anti-alcohol experiments of 4 classes， the ADH activation ratio of the G4 fraction was as high as 90.12%， so corn peptide with facilitating alcohol metabolism activity was enriched efficiently. Ultra-performance liquid chromatography tandem mass-spectrometry （UPLC-ESI-Q-TOF-MS/MS） was applied for structural identification of the G4 fraction separated by Sephadex G-15. Six peptides with length ranging from 7 to 9 amino acids were found by searching against the corn data from Uniport database， including GQAIILP， GGTALPA， QAKGILP， YQQPIIGGA， VAAGGPA， VAVGGVP， 3 of them contained leucine， all of them contain alanine， These two amino acids played an important role in facilitating alcohol metabolism activity. In addition， Proline also had a positive effect on facilitating alcohol metabolism. In conclusion， it was suggested that the corn hydrolysates could be used in the potential functional ingredients with anti-alcoholism effect. This will greatly help to provide theoretical and technical guidance preparation of corn peptides with excellent anti-alcoholism properties.

Abstract:To explore the role of resistant starch in fermented milk， RS2 type potato resistant starch （G） and microwave-wet heat method were used to prepare RS3 potato resistant starch （W）， and their content and morphology during fermented milk processing and storage were observed. The change was observed. The fermented milk without added resistant starch was used as a control to observe the microstructure and analyze the rheological properties and stability of the fermented milk gel process. The results showed that the residual amount of W relative to G was higher and maintained at about 60%； both resistant starch retained the morphology of starch granules， but there were different degrees of loss， mainly concentrated in the late fermentation and storage period. W was more helpful for the fermented milk to form a complete and uniform microstructure； the fermented milk containing W had strong micro-elasticity and contributed to the combination of casein particles to form a more robust structure； the micro-stability of the fermented milk containing W was superior to that of fermented milk containing G.

Abstract:The inductively coupled plasma emission spectroscopy （ICP-OES） method was used to determine the selenium-enriched amount and selenium conversion rate， and the two strains of Lactobacillus rhamnosus Lr-1 and Lr-2 with strong selenium-enriched ability were explored in the process of continuous passage for 250 generations. The selenium-enriched capacity was investigated to determine its selenium-enriched stability. On this basis， the response surface method was used to optimize the ratio of the selenium-enriched L. rhamnosus lyophilized protectant. The results showed that the morphology of the strain did not change significantly during the passage of 250 generations. The average selenium content of Lr-1 was 429.99 μg/g， and the average selenium conversion rate was 28.32%. The average selenium content of Lr-2 was 398.14 μg/g， the average selenium conversion rate was 25.57%， and the selenium-enriched ability was relatively stable. The best cryoprotectants for the selenium-enriched L. rhamnosus was 7% trehalose， 10% skim milk powder， 5% sodium glutamate， and its lyophilization survival rate was 89.86%， which was better than no cryoprotectants. The lyophilization survival rate was increased by 81.85%. This study provided a theoretical basis for the development of selenium-enriched lactic acid bacteria food.

Abstract:Cordyceps carotenoid is a water-soluble natural pigment with anti-inflammatory， anti-oxidation， immune regulation and other effects. It has a wide application space in the food industry and is a new type of pigment that needs to be developed. In this study， the medium of three high-yield carotenoid strains was optimized by using cereal medium. The results showed that the highest-yield carotenoids strain was CM10 and the optimal medium was 73% wheat， 20% bran and 7% corn. The strain CM10 was used to optimize the conditions of solid state fermentation through single factor and response surface methodology. And the optimum operating conditions were determined as particle size 10 mesh， initial moisture content 48%， growth time of mycelium in the dark 12 d， growth temperature of mycelium in the dark 22 ℃， natural pH， inoculum size 25%， substrate weight 25 g， illumination temperature 25 ℃， illumination time 14 d， the production of carotenoids was 346 μg/g.

Abstract:In this paper， apple， pomegranate and brown plum were used as raw materials to prepare composite juice. Sensory evaluation of different proportions of composite juice was carried out to determine the best ratio， and the effects of high hydrostatic pressure （HHP） treatment parameters （treatment pressure， holding time） on the microbes and quality of composite juice were studied. The optimal compounding ratio of the composite juice was mapple juice ∶ mpomegranate juice ∶ mbrown plum pulp =16 ∶ 3 ∶ 1. After 400 MPa/5 min， 500 MPa/1 min， 500 MPa/3 min and 500 MPa/5 min treatment， the counts of total aerobic bacteria and yeasts and molds met the requirements of ‘Chinese National standards for food safety Beverages GB 7101-2015’. Compared with the untreated group， HHP treatment and heat treatment had no significant effects on the pH， total soluble solids （TSS） and color of the sample. The total phenol and ascorbic acid content of HHP-treated samples were not significantly different from heat-treated ones， but the DPPH removal ability and ferric ion reducing antioxidant power （FRAP） of the HHP-treated samples were significantly higher than heat-treated ones. The DPPH removal ability of HHP-treated samples was 8.57%-18.10% higher than heat-treated ones， and the FRAP was 11.50%-24.78% higher. HHP treatment increased the viscosity of the samples， while heat treatment reduced the viscosity of the samples. Both HHP treatment and heat treatment changed the volatile aroma components of the samples， but the content of the retort component after heat treatment increased more. The passivation effect of HHP treatment on endogenous enzyme activity was worse than that of heat treatment， and the residual enzyme activity of polyphenol oxidase （PPO）， peroxidase （POD） and lipoxygenase （LOX） was between 65.13%-76.97%， 75.00%-85.42% and 75.00%-85.00% in HHP-treated samples， respectively， while 15.35%， 7.29% and 45.00% in heat-treated ones.

Abstract:The present work investigated the effects of heat treament on the interactions of myofibrillar protein with fishy odor compounds. Four typical fishy odor compounds were selected and the myofibrillar protein-fishy odor compounds system were established. The changes in the structures of myofibrillar protein and binding capacity with volatile compouns during one-stage heating process of surimi were determined by UV spectra， fluorescence spectroscopy， Raman spectroscopy and head-space sampling combined with gas chromatography-mass spectrometry （HS-GC-MS） technology. The results showed that the turbidity， surface hydrophobicity and total sulfhydryl content of myofibrillar protein solution increased first and then decreased with the extension of heat treatment time（P<0.05）， and the endogenous fluorescence intensity of protein decreased gradually. Within 0-5 min of heating， the content of α-helix decreased significantly（P<0.05）， while the β-sheet and β-turn content increased obviously （P<0.05）. Subsequently， the content of α-helix increased and the β-sheet decreased when the heating time exceeded 5 min. The binding capacity of volatile aldehydes to myofibrillar protein was significantly influenced by the heating treatment. At the initial stage of heating， the structure of myofibrillar protein was unfolded and the binding ability with the aldehydes was significantly enhanced（P<0.05）. The binding capacity of hexanal， heptanal and nonanal reached the maximum at 5 min of heating， while that of octanal reached the maximum at 2 min. After that， the binding ability decreased significantly with the prolongation of heating time （P<0.05）.

Abstract:In this paper， rice bran protein was used as raw material， and it was modified with transglutaminase （TG）. The single factor experiment and response surface optimization experiment were used to study the effects of the protein mass fraction， modification time， and enzyme dosage on the protein gel hardness of modified rice bran. And the solubility， emulsifying and stabilizing properties， the foaming property， foaming stability， and oil holding property of rice bran protein before and after modification were compared. The results showed that the optimal gel hardness was obtained at a protein mass fraction of 12.8%， a modification time of 3.2 h， and an enzyme addition amount of 19.7 U/g and the gel hardness was 93.58 g. After the modification treatment， the protein water holding capacity， the solubility， emulsification and emulsification stability， foaming property and foaming stability， oil holding capacity increased by 162%， 31.1%， 52.7%， 25.4%， 33.3%， 7.2%， 114%， respectively. The microstructure of the modified rice bran protein was similar to the sponge structure observed by scanning electron microscopy. The structure of the modified rice bran protein were significantly improved， which indicated that the modified rice bran protein had a significant effect.

Abstract:To study the effects of steam explosion sweet potato residue on the physicochemical properties of starch in wheat flour and the quality of bread， steam explosion sweet potato residue was added to the high gluten wheat flour， and measured the damage， solubility， swelling power， relative viscosity， retrogradation of starch in mixed powder and the quality characteristics of bread products. The results showed that there was significant difference of the damage of starch granule and blue values between the addition of 6% steam explosion sweet potato residue and the control （P<0.05）. When addition amount of the steam explosion sweet potato residue was 10%， the value of starch solubility and swelling power of the mixture reached the maximum value， （7.69 ± 0.04）% and （3.53 ± 0.08）%， respectively. The viscosity of starch in wheat flour decreased with the increase of the amount of steam explosion sweet potato residue. And with the addition amount of steam explosion sweet potato residue increasing， the retrogradation value of starch increased. According to results of the texture properties and organoleptic evaluation， the qualities of the bread made by the mixture was best when the 8% steam explosion sweet potato residue was added to the high gluten wheat flour.

Abstract:Objective： Bifidocin A， produced by Bifidobacterium animalis BB04， is a novel bacteriocin with antimicrobial activity against a wide range of foodborne bacteria， which can be used in the processing and storage of food as a natural biopreservative. The study aimed to investigate the application feasibility of bifidocin A in the production， processing and storage of set yogurt. Methods： Set the different concentrations（56， 28 and 14 mg/mL） of the bifidocin A treatment group， controlled by 50 mg/mL nisin. The effects of bifidocin A on its product quality and storage performance were analyzed by measuring the pH， titratable acidity， water holding capacity， the number of viable counts， texture， rheology， volatile flavor substances of the set yogurt during storage for 28 d. Results： Adding 28 mg/mL bacteriocin bifidocin A can maintain acidity < 110 °T， pH > 4.2 and viable count > 108（CFU/mL） during 28 d storage period， and the water holding capacity of the yogurt and the volatile flavor substances are significantly improved. Conclusion： The bacteriocin bifidocin A can be added to the set yogurt as a natural preservative to replace nisin to improve its product quality and storage performance， and the optimal addition amount of bacteriocin was 28 mg/mL.

Abstract:Objective： The effects of the ratio of composite wall materials on the storage stability of yolk lecithin microcapsules were studied and the best ratio was determined. Method： Egg yolk lecithin microcapsules were prepared by spray drying method with egg yolk lecithin as core material， maltodextrin and gum arabic （mass ratio 1 ∶ 3， 1 ∶ 1 and 3 ∶ 1） as wall materials. The differences of physiochemical properties and morphology of the microcapsules prepared with different wall materials were studied. The changes in embedding rate， color （L*， a* and b*） and TBARS value of egg yolk lecithin microcapsules were analyzed by accelerated oxidation test. Result： The solubility， fluidity and surface morphology of the prepared microcapsules were all good， while maltodextrin and gum arabic with the mass ratio of 1 ∶ 3 or 3 ∶ 1 had better embedding effect （66.40% and 66.52%， respectively）. With the increase of maltodextrin ratio in the wall material， the embedding rate and color of microcapsules were more stable， and the oxidation degree of egg yolk lecithin was decreased. Conclusion： The storage stability of egg yolk lecithin microcapsules was better with the optimal mass ratio （3 ∶ 1） of maltodextrin and gum arabic.

Abstract:A strain of Bacillus subtilis（BS08） was used as feed additive to study the effects on intestinal flora of tilapia， especially on the adherence， colonization and breeding capacity of spoilage bacteria from intestinal flora of tilapia during ice storage after being fed with Bacillus subtilis. At the same time， the effects of BS08 on delaying spoilage of iced-storage tilapia was also studied. Four treatments were grouped by feeding with Bacillus subtilis and adding spoilage bacteria （Shewanella and Pseudomonas） in water or not. The influences of Bacillus subtilis and spoilage bacteria on intestinal flora of iced storage tilapia from four treatment groups were determined by high throughput sequencing. The TVB-N and K values were used as the corruption index of iced-storage fish. Bacillus subtilis showed the ability to maintain the diversity of the intestinal flora of tilapia and repress the changes of the intestinal flora of tilapia. The degree of colonization of Shewanella in the intestine is greater than that of Pseudomonas. Bacillus subtilis could colonize in the intestine of fish and inhibit the colonization of Shewanella to significantly repress the dominant growth of Shewanella. TVB-N and K value indicated that Bacillus subtilis significantly delayed the corruption of iced-fish.

Abstract:Inhibition of compound spice extracts （cinnamon， clove and star anise） and vacuum packaging on biogenic amines accumulation in dry sausage during storage was investigated in this study. Meanwhile， the change of physicochemical properties， microorganism， and sensory quality in dry sausage was also studied. The results showed that the addition of a compound spice extract combined with vacuum packaging effectively inhibited the accumulation of biogenic amines （tyramine， cadaverine， putrescine， histamine， 2-phenylethylamine， and tryptamine） in dry sausage during storage， and reduced the increasing of pH and total volatile base nitrogen value. Compound spice extracts and vacuum packaging also decreased the oxidation of fat， and the growth of total aerobic bacteria， lactic acid bacteria， and enterobacteriaceae. In addition， vacuum packaging significantly reduced （P<0.05） the loss of moisture， and maintain the sensory quality of dry sausage， and the addition of compound spice extract significantly improved （P<0.05） the sensory quality of dry sausage. The principal component analysis showed that the accumulation of biogenic amines in the dry sausage was closely related to the changes of total aerobic bacteria， lactic acid bacteria， Enterobacteriaceae， pH， TVB-N and TBARS value. Thus， compound spice combined with vacuum packaging effectively inhibited the accumulation of biogenic amines and reduced the quality deterioration of dry sausage during storage.

Abstract:Streptococcus （St.） thermophilus is one of the most commonly used starters in fermented milk production. In the present study， St. thermophilus IMAU80285 isolated from the traditional fermented dairy product qula with specific flavor properties was selected and detected for the flavor substances produced during the production and storage of fermented milk， by gas chromatography-mass spectrometry methods. Principal component analysis and similarity analysis was then used to systematically analyze the flavor components. The results showed that the total of 84 volatile compounds were finally detected in fermented milk during fermentation and storage， including aldehydes （13 species）， ketones（12 species）， acids （11 species）， esters （9 species）， alcohols （22 species）， hydrocarbon compounds （14 species） and nitro-gen-containing compounds （3 species）. Principal component analysis revealed that the apparent distinction in the flavor substance （OAV ≥ 0.1） between the initial stage of fermentation （4， 6 h of fermentation） and the completion of fermentation and whole storage period （after ripening， 1， 2， 3， 7， 14 d）. At the beginning of fermentation （4， 6 h of fermentation） and at the completion of fermentation， there were positive correlations with 17 kinds of flavor substances with OAV ≥ 0.1， such as acetoin， heptaldehyde， 1-nonanol and ethyl hexanoate； while positive correlations were observed with 7 kinds of flavors with OAV ≥ 0.1， such as 2，3-butanedione， 3-methyl-1-butanol and ethyl butyrate during storage （after ripening， 1， 2， 3， 7， 14 d）. The results of overlapping chromatogram and similarity analysis showed that the flavor substances in fermented milk changed significantly during the production and storage of fermented milk. It is obviously noting that significant difference in composition of flavor substances with the increase of storage time.

Abstract:Proteomic analysis of Lactobacillus plantarum could provide a theoretical basis for mechanism of manganese involved in metabolism of lactic acid bacteria. Growth of Lactobacillus plantarum DY-2 was observed under the cultivation with or without manganese， and protein expression was analyzed using iTRAQ technology. Bacteria culture were collected at 6 h and 9 h of the mid-logarithmic growth phase for proteomic analysis. Based on iTRAQ results， fifty-six intracellular proteins were identified having differential expression after 6 h with lack of manganese， and these 56 proteins include 31 up-regulated proteins and 25 down-regulated proteins. Seventy-eight intracellular proteins were identified having differential expression after 9 h with lack of manganese， while the expression level of 40 proteins was up-regulated and 38 proteins was down-regulated. Sixteen proteins were found to have significant differences at both time points. Proteins involved in the construction of ribosome were down-regulated with lack of manganese， while the up-regulated proteins were involved in DNA repair and stress response， and UspA family proteins did show significant difference in the fermentation process. GO analysis and KEGG metabolic pathway analysis revealed that manganese have a significant impact on metabolism pathway in L. plantarum， such as pyruvate and amino acid metabolism.

Abstract:The aim of this research was that using technology of simultaneous saccharification and fermentation to ferment three different carbon sources （glucose， corn starch gelatinization solution， corn starch） to produce L-lactic acid and proteomics to analysis the difference of the production under three carbon sources by Bacillus coagulans BCS13002. The results showed that the content of L-lactic acid were （10.23 ± 0.16） g/L， （11.75 ± 0.20） g/L， （0.26 ± 0.02） g/L under the carbon sources of glucose， corn starch gelatinized liquid， corn starch liquid conditions， respectively. Furthermore， 454 differential expressed proteins were identified under three different carbon sources and these were mainly involved in the glycolysis/gluconeogenesis and tricarboxylic acid cycle pathways， followed by HIF-1 signaling pathway， pyruvate metabolism， carbon metabolic， pantothenic acid and CoA biosynthesis， fructose metabolism， two-component system. Moreover， the Bacillus coagulans BCS13002 could not produce the L-lactic acid with using corn starch liquid by glycolysis/gluconeogenesis metabolism pathway. Above all the content of L-lactic acid mainly related to the difffernetial proteins in the glycolysis/gluconeogenesis and tricarboxylic acid cycle metabolism.

Abstract:Rapid evaporative ionization mass spectrometry （REIMS） is a recently developed ambient mass spectrometric technique without any sample preparation. In this study， a real-time lipidomics detection method was developed for fast profiling of Antarctic krill oil on the basis of REIMS. The Antarctic krill oil was extracted using 95% ethanol from freeze dried Antarctic krill. The compounds inside were evaporated by a heating probe at 500 ℃， and the aerosol generated was transferred into the interface of mass spectrometer by a Venturi pump with nitrogen at 2 bar. In the interface， a coil of Kanthal A1 wire （1.1 Ω， 3 V） was set for ion collision. A syringe pump was used to inject the matrix solvent at a flow rate of 0.1 mL/min throughout experiments. The propan-2-ol， together with the aerosol， entered the mass spectrometer via a stainless steel MS inlet capillary. The results showed that the lipid ion peaks were generally produced in the m/z range of 200-900. There are generally two clusters， including the cluster of fatty acid ions at m/z 200-500 and the cluster of phospholipid ions at m/z 600-900. After statistic analysis and lipid identification， a total of 20 fatty acid molecular species and 26 phospholipid molecular species were found. [EPA-H]- （m/z， 21.59%） and [DHA-H]- （m/z 327， 14.44%） were the most abundant fatty acid ions， while [PG 36：7-H]- （m/z 763， 11.67%） and [PC O-38：3-choline]-/[PE O-38：3-NH3]- （m/z 737， 11.46%） were the major phospholipid ions. After method validation， it indicated that the proposed REIMS method was sensitive and precise for high-throughput lipidomics profiling of Antarctic krill oil， which could provide important theoretical basis for mass spectrometry workers and technical support for related enterprise and functional departments.

Abstract:This study established a DNA barcoding method for the identification of salmonids and then detected 17 commercial salmonid-derived products using this method. The gene fragments of DNA cytochrome C oxidase I （COI） and 16S ribosomal RNA （16S rRNA） were amplified from the samples for Sanger sequencing. The authenticity of the analyzed samples were identified by comparing and analyzing the sequences. For salmonid-derived products that were composed of a single species， the results indicated that species identification could be achieved by using COI as the target and 16S rRNA as the auxiliary target. Thus， our study confirmed DNA barcoding as an effective tool to identify the authenticity of salmonids， which could provide strong technical supports for supervision of salmonids market.

Abstract:Objective： Isolation and identification of antioxidant peptide with high ABTS+· scavenging capacity from tryptic hydrolysate of Ovalipes punctatus waste containing meat scraps. Method： Antioxidant peptides in the hydrolysates were purified using ultrafiltration membrane system， Sephadex G-15 column and semi-preparative reversed-phase high-performance liquid chromatography （semi-preparative RP-HPLC）. Their peptide sequences were identified by ultra-performance liquid chromatography/electrospray ionization time-of-flight tandem mass spectrometry（UPLC-ESI-TOF/MS/MS）. Their structure and ABTS+· scavenging capacity were further verified by the synthetic peptides. Results： Two peptides with high ABTS+· scavenging capacity were purified from hydrolysates， and their peptide sequences were Tyr-Glu-Gly （YEG） and Tyr-Glu（YE）， respectively. The molecular weight of synthetic peptides was 367.35 u and 310.30 u， and their purity was 98.52% and 98.04%， respectively. The synthetic peptides YEG and YE have good ABTS+· scavenging capacity， with IC50 values of 0.456 mg/mL and 0.184 mg/mL， respectively. Furthermore， IC50 value of synthetic peptide YE was 30.30% higher than that of reduced L-glutathione. Conclusion： Antioxidant peptides were existed in the tryptic hydrolysate of Ovalipes punctatus waste containing meat scraps， which provides a theoretical basis for development of antioxidant peptides from Ovalipes punctatus by-products.

Abstract:Objective： To establish a rapid method of classifying marking age and brand of Chinese rice wines， which was detected by gas chromatography-ion mobility spectrometry （GC-IMS）. Method： The volatile organic compounds （VOCs） in 5-year marking age and 3 company brands Chinese rice wines samples were detected by GC-IMS method with automatic headspace sampling system and datas were processed with principal component analysis（PCA）. Result： The amounts of volatile compounds in Chinese rice wines samples were obviously different， marking age and brand could be distinguished by the VOCs fingerprints， 3-5 years marking age "Guyuelongshan" rice wine samples could be quickly distinguished with 8-20 years marking age by the fingerprints， while it was difficult to distinguish difference between 3-year and 5-year marking age wine， between 8-year and 20-year marking age wine with this method. A improvement method to discriminate difference among all marking age and company brands wines were performed by measuring hue angle from VOCs fingerprints with photoshop software. There were no significant difference of ethyl acetate content among all the samples， and slightly change of dimethyl disulfide content， while remarkable differences were found in benzaldehyde， 3-methylbutyl acetate and 2-butanone among 7 samples， which could be used for distinguishing marking age and brand of the Chinese rice wine. Chinese rice wines could be classified accurately by PCA， and some interesting regularity were shown in the score plots with the help of PCA. Conclusion： GC-IMS combined with PCA was a useful and reliable technology for intuitive discriminating marking age and brand of Chinese rice wine， and it had potential wide application prospect in rice wine quality evaluation.

Abstract:A rapid UHPLC-LTQ-Orbitrap MSn method was established for the identification of chemical profile in daylily flowers. Chromatographic separation was achieved on Hypersil Gold AQ RP-C18 column （100 mm×3.0 mm，1.9 μm） with the mobile phase of 0.1% formic acid-water and 0.1% acetonitril-water in gradient elution. High resolution mass spectrometry analyze the multilevel mass spectrometry data in positive ionization mode and qualitative the chemical profile. According to retention time， ultraviolet absorption， the accurate mass measurements， mass fragmentation patterns and literature reports， a total of 27 compounds including 12 phenolic acids， 15 flavonoids， and 1 other compound were tentatively screened and characterized. The method can efficiently， quickly， sensitively and comprehensively analyze the chemical profile of daylily， and provide a theoretical basis for the study of the pharmacological of daylily. Moreover， it could be useful for the structural identification of similar compounds.

Abstract:This paper took soy sauce as the research object to study the application of the electronic tongue technology on soy sauce. Principal component analysis（PCA）， discriminant factor analysis（DFA） and BP neural network （BPNN） were used to identify different brands of soy sauce. Partial least squares method（PLS） was used to establish a quantitative model of the taste components such as amino acid nitrogen， total acid， total sugar， salt， bitter amino acids， umami amino acids and the output value of electronic tongue to achieve the purpose of predicting the content of taste components. The optimal conditions for the electronic tongue to identify soy sauce were as follow： the dilution multiple was 30 times， sourness， bitterness， umami， saltiness， sweetness and richness were chosen as the taste indexes for evaluation， and washing time before full sensing was 6 s. The results showed that the electronic tongue technique had the ability to classify soy sauce in different brands. The contribution rate of the first two principal components of PCA and DFA were 83.8% and 98.1%， respectively， and the correct discrimination rate of the fishers’ function was 99.3%. BPNN had the ability to predict unknown samples accurately and the correct discrimination rate reached 100%. It could be seen that the PLS model showed excellent ability to predict the contents of physicochemical indexes accurately by the electronic tongue.

Abstract:In this study， the samples of Tan sheep， small tail Han sheep and Tan Han hybrid sheep were researched by macrogenomics to discuss the intraspecific polymorphism of sheep breeds which were easy to be confused. The whole genome of mixed samples was sequenced by high throughput sequencing， and the genetic diversity of sheep population was evaluated and analyzed. The SSR site of the splicing sequence was found by MISA. SSR sequence analysis and then designed as a fluorescent marker primer through PRIMER3 Input （version 2.3.7）. Finally， the genetic diversity of Tan sheep， small tail Han sheep and Tan Han hybrid sheep was analyzed by polymorphism SSR markers. The sequencing results showed that the sequence information of the whole genome of the mixed sample with the total size of 6.1 GB was obtained， and the average fragment length of the sequence was 150 bp. It was found that compound SSR repeats existed， and the ratio of 3 / 2 / 1， 2 / 1 and 1 / 3 of the number of units was higher， and the total number of the three patterns accounted for 87.35% of the total number of complex repeats. 46 polymorphic markers were screened from 100 pairs of SSR primers， with a polymorphic rate of 46 and an average PIC value of 0.358. The samples of three species of Sheep genus and three mixed mutton species of sheep genus were grouped into one group， respectively， and showed monophyletic properties. The results are valuable for the study of sheep genome engineering， the development of molecular markers among sheep species and the identification and protection of germplasm resources.

Abstract:The diverse effects of different sources of trans fatty acids on human health have been reported. Therefore， the objective of this study was to investigate the composition and content of trans C16：1， trans C18：1， trans C18：2 and CLA isomers in food， and provide scientific theory for studying the relationship between trans fatty acids， CLA and heath in different foods. Determination of trans C16：1， trans C18：1， trans C18：2 and CLA isomers in ruminant animal fat， edible oils and frying oils by combining silver ion solid phase extraction column and the two heating programs of gas chromatography. Result showed that 23 trans fatty acids were detected in the sample， of which 7 were trans C16：1， 10 trans C18：1， 6 trans C18：2 and 6 were CLA isomers. The trans C16：1， trans C18：1 and CLA in ruminant fats were significantly higher than those in edible oils and frying oils， while the trans C18：2 content in frying oils was higher. 9t C16：1，11t C18：1 and 9t12t C18：2 were the main trans fatty acid isomers in ruminant animal fat， and the main CLA isomer was 10t12c CLA， while 12t C16：1， 9t C18：1， 9c12t C18：2 and 9t12c C18：2 are the main trans fatty acid isomers in edible oil and frying oil， and the main isomers of CLA were 10t12c CLA and 11c13t CLA. Comparing edible oil edible and frying oil， the fatty acid composition of camellia oil had the smallest change， while the content of trans C18：2 and trans C18：1 in most frying oils significantly increased compared with those in unfried oils. It can be seen that the major trans fatty acid isomers in ruminant animal fat， edible oil， and frying oil are different， while the effects of different isomer fatty acids on human health are diverse. Camellia oil is suitable for frying， and edible oil rich in polyunsaturated fatty acids will produce more trans C18：2 after frying， which has greater potential for human health than trans C18：1， therefore， the control of frying oil quality should be paid great attention.

Abstract:The aim of this study was to explore the bacterial diversity and the main special flavor of the stinky egg， using PCR-DGGE and HS-SPME/GC-MS technology. The result indicted that a total of 42 microorganisms were found in the whole stage， and 12 species belonging to Marinobacter， Halanaerobium， Marinilactibacillus， Halomonas， Paraliobacillus， Halolactibacillus and Uncultured bacterium. In the early stage （0-7 d） and middle stage （8-21 d） of fermentation， the biomass of Halomonas was the highest， accounting for 26.94% and 30.97%， respectively. Paraliobacillus was the major bacteria during the late stage（22-28 d）， the microbe abundance was 23.96%. During the final stage of fermentation （29-60 d）， Marinilactibacillu and Halomonas are the dominant microorganisms. The strain Paraliobacillus sp. Band 12 and strain Halomonas sp. Band 25 were the dominant microorganism species involved in the whole fermentation stage. In the stinky egg， a total of 18 special flavor were detected， such as dimethyl trisulfide， dimethyl disulfide， 4-methyl valeric acid， butyl 3-methylbutyrate， butyric acid and 2-methylhexanoic acid. Finally， the present research enriches the knowledge of the traditional fermented food-related bacteria， as well as improve the quality and safety of the stinky egg.

Abstract:A new type of vitro nucleic acid isothermal amplification method-saltatory rolling circle amplification （SRCA） was established to detect Salmonella. The primers were designed using the specific gene stn of Salmonella and the specificity was verified. The performance of the assay was evaluated with respect to sensitivity and the detection limit of artificially contaminated chicken was tested. In addition， the sensitivity， specificity and accuracy were evaluated by testing a variety of real food samples. Results： All Salmonella presented positive results， but non-Salmonella gave negative results， indicating good specificity of the primer. The sensitivity of SRCA method was 5.6×100 fg/μL for DNA， and the detection limit was 3.8×101 CFU/mL. The sensitivity of PCR method was 5.6×102 fg/μL， and the detection limit was 3.8×103 CFU/mL. In addition， the detection rate of this method for detecting 30 real samples was 13.33%. Compared with the GB 4789.4-2016， the sensitivity， specificity and accuracy of SRCA were 100.00%， 96.30% and 96.67%， respectively. Conclusions： The method has the advantages of simple operation， high specificity， high sensitivity， low detection limit， low cost and low equipment requirement， and is suitable for the rapid detection of Salmonella in food.

Abstract:The Campylobacter jejuni real-time PCR rapid detection kit was developed， and validated according to the AOAC microbiology method validation guidelines. The specificity of the kit was 100% for the 115 target strains and 118 non-target strains， and the sensitivity reached 6.4 CFU/mL. The Ct values for repeated freezing and thawing for 30 times didn't show significant differences. Robutstness results showed that the enrichment broth volume， heating lysis time and the DNA volume in PCR reaction didn't have any influence on the PCR result for the 11 Campylobacter jejuni and 5 non-target Campylobacter strains， except for one Campylobacter jejuni strain， for which high volume of enrichment broth can inhibit PCR reaction. The combined lot-to-lot and stability test showed the three lots （newly produced， 4 months after production， 1 year after production） gave consistent results for the 16 strains， and the Ct values for the 11 Campylobacter jejuni were similar. Consistent results were shown both for the kit method and conventional method in the innoculation of Campylobacter jejuni in chicken， vegetable and milk samples， as well as in practical chicken sample detection， and there was no “false negative” using the kit method. Our kit is open， can be used on various real-time PCR platforms， contained the internal amplification control which can avoid the “false negative result”， and can be applied in the rapid detection of Campylobacter jejuni from food.

Abstract:Smoking and roasting during meat processing can produce special appearance and flavor， but also can form some harmful substances， such as heterocyclic aromatic amines（HAAs）. There are two classes of HAAs： pyrolytic HAAs （>300 ℃） and thermic HAAs （100-300 ℃）. Epidemiological results show there were a obvious relationship between human daily intake of well-done meat products with increased HAA levels and an enhanced risk of digestive system cancer. This review focuses on the classification， carcinogenic and metabolic of HAAs. Additionally， the formation kinetics and mechanism of HAAS in model system were discussed. Finally， the different extraction and detection methods of HAAs were introduced， and some problems needed be resolved in HAA study are discussed. This review provides a theoretical support to the study of HAAs.

Abstract:In recent years， the health benefits of probiotics have been continuously confirmed， and research on probiotics and human health has attracted global attention. The purpose of this paper is to focus on the current research trends of probiotics science， and make the judgments on the common issues that urgently need to be resolved in this field. Based on the analysis of the literatures on probiotics during 2001-2020， the top 10 research trends were illustrated， including， the probiotics and gastrointestinal health， immune regulation， metabolic syndrome， gut-X axis， probiotics-diet interaction， prebiotics/postbiotics， the latest technologies， edible safety， precision probiotics and the next-generation probiotics. At the same time， the proposal related to industrial technology， basic research， standards and regulations， the science popularization were also provided for the scientific study and industry development of probiotics in China.

Abstract:In recent years， probiotics have gained wide popularity due to their association with health and wellbeing. Based on the bibliometric evaluation approach， the number of literatures， source journals and research hotspots were compared and analyzed for probiotics-related papers in the Chinese National Knowledge Information （CNKI） database and the Web of Science（WOS） database. The results showed that the research hotspots of probiotics are mainly related to three areas： probiotics and human health， probiotics and foods， probiotics and breeding industry. But the publication volume of probiotics in CNKI was much lower than that in the WOS. This paper systematically analyzed the similarities and differences in research hotspots in the field of probiotics in order to provide references for the better development and future of probiotics industry in China.

Abstract:Since the outbreak of the COVID-19， the Party Central Committee with Xi Jinping at its core has made a series of comprehensive arrangements for the overall promotion of epidemic prevention and control and economic and social development. As an important component of Chinese food industry， the health food industry meets the health needs of special populations and contributes huge economic and social benefits. In order to further understand the consumption of health food by the general public， and to grasp the policy needs of the health food industry under epidemic situation and subsequent development， this article systematically analyzes the current health food consumption situation by conducting a questionnaire survey on some health food companies in China. At the same time， combined with market demand， it proposes market supervision policy recommendations to promote the development of the health food industry.