Abstract:Although starch with natural B-type crystal structure is a typical type 2 resistant starch， most of them have to undergo varying degrees of thermal processing before consumption， resulting in a significant decrease in enzymatic resistance. Under certain conditions， even the digestible starch could escape digestion in the small intestine and enter the colon to be utilized by microbiota， which， however， has rarely been reported. The present study prepared a series of potato starch samples with different gelatinization degrees (DG) and investigated the fermentability by human fecal microbiota in an in vitro batch system. Gas production increased from 9.8 mL of gelatinized starch with low DG (DG 16) to 14 mL of gelatinized starch with high DG (DG100) during the first half of fermentation (0-12 h)， and the acetate and propionate production also gradually increased with increasing DG. For instance， the yields of acetate (67.26 mmol/L) and propionate (61.19 mmol/L) of high gelatinized starch sample(DG100) were significantly higher than those of low gelatinized starch sample (DG16， 41.29 mmol/L of acetate， 21.27 mmol/L of propionate). Compared with other groups， gelatinized starch groups with low and medium DG (DG16， DG49) exhibited the higher butyrate yields at the end of fermentation. Moreover， Roseburia， Lachnospiraceae and Blautia were promoted by gelatinized starches with low and medium DG. Compared with other groups， gelatinized starch groups with medium and high DG (DG49， DG65 and DG76) promoted the proliferation of Megamonas， and generated higher levels of acetate and propionate. The proliferation of butyrate-producing bacterial and higher production of butyrate by gelatinized potato starch with low and medium DG (DG 16 and DG49) suggested that these starches could potentially improve the colon health function.

Abstract:The screening of traditional antioxidant peptides often needs enzymatic hydrolysis， purification， separation， identification and in vitro experimental verification， which costs a lot of time and material resources. Based on bioinformatics， this study used computer virtual digestion， prediction and evaluation of related activities， pharmacokinetics and molecular simulation techniques to screen antioxidant peptides from bovine whey protein in turn， analyze and explain the possible mechanism of Keap1-Nrf2-ARE antioxidant pathway， and analyze the stability of conformation in the process of molecular reaction. Using the Peptideranker program to predict and score the biological activity， 137 peptides with a score greater than 0.4 were screened. At the same time， Toxinpred， Innovagen， Expasy-compute and Pepdraw programs were used to further predict and analyze the physical and chemical properties of the peptides. Through pharmacokinetic ADMET and TOPKAT analysis， 14 peptides with no toxicity， no sensitization， no mutagenicity， no carcinogenicity and good water solubility were screened. Then it was docked with Keap1 receptor， and the conformational mechanism of the polypeptide with the top four docking scores was analyzed with the optimal binding complex of Keap1. Finally， through the evaluation of the intermolecular force of the complex conformation， it was concluded that the CDEF sequence had the most antioxidant activity potential， and the CDEF-keap1 receptor complex was simulated by molecular dynamics. The results showed that the conformational change was relatively stable in the process of dynamic simulation. Therefore， CDEF antioxidant peptides could play a better role in antioxidant activity in human body. Compared with traditional enzymatic hydrolysis methods， this study could quickly and efficiently screen antioxidant peptides， and provide a new idea for the rapid screening of antioxidant peptides from natural food sources.

Abstract:Objective: Pseudomonas fluorescens is the dominant spoilage organism in frozen foods， and its spoilage-causing genes are regulated by quorum sensing system. In order to accurately quantify the expression of spoilage genes and thus investigate the mechanism of quorum sensing regulation in food spoilage， it is required to screen reference genes of Pseudomonas fluorescens. Methods: Using Pseudomonas fluorescens PF-08 as the research object， eight common reference genes (dsbA， carA， rpsL， gyrB， atpD， rpoD， gltA， 16S rRNA) were selected and their gene expression was measured by quantitative real-time PCR (qPCR) after incubation with different types of quorum sensing signal molecules. geNorm， Normfinder， BestKeeper and RefFinder were used to evaluate the expression stability of the candidate reference genes and to screen out the most appropriate reference genes. Results: Under different types of exogenous signal molecules incubation， the least change in Ct value of Pseudomonas fluorescens was gltA and the Ct value of 16S rRNA was too low. The most stable reference genes by geNorm analysis were atpD and rpoD and the combination of the two could more accurately quantify the expression levels of target genes. gltA was the most stable reference gene analyzed by Normfinder and BestKeeper. Further comprehensive evaluation with RefFinder showed rpoD and gltA were the most stable reference genes. Conclusion: Both rpoD and gltA were stably expressed in Pseudomonas fluorescens after incubation with different QS signal molecules. They could be used for the subsequent study of Pseudomonas fluorescens spoilage gene expression， and could also provide reference genes for studying the expression of QS-related genes in other spoilage bacteria.

Abstract:In order to study the effect of epigallocatechin on the oxidation of myosin in sea bass under microwave heating，differentmass concentrations of epigallocatechin (20，40 μg/mL and 60 μg/mL) were used to inhibit myosin oxidation and study the mechanism of its effect on myosin. EGC could delay the increase of carbonyl content and dityrosine of myosin and the decrease of total sulfhydryl content after microwave treatment. Carbonyl content was reduced by 19.82%-72.67% compared with the control. AFM showed that the myosin treated with EGC were small and evenly distributed. Microwave induced myosin to unfold and increased fluorescence intensity. EGC maintained the relative stability of the tertiary structures and delayed the increase of fluorescence intensity.Before microwave， low mass concentration EGC (20， 40 μg/mL) significantly increased α - helix content and maintained the stability of myosin secondary structure. After microwave， 20 μg/mL EGC maintained the stability of secondary structure. Molecular dynamics simulation showed that RMSF and RMSD value of myosin-EGC decreased， SASA decreased， secondary structure fluctuation decreased. It was found that myosin enhanced the stability of the complex under heating electric field by hydrogen bonding and hydrophobic interaction with EGC.

Abstract:This study investigated the changes of structure and functional properties of insoluble dietary fiber (IDF) from lotus root residue before and after alkaline hydrogen peroxide (AHP) treatment. Results showed that D-glucose content of lotus root residue IDF increased significantly by 9.52% (P<0.05)， while the contents of other monosaccharides decreased significantly (P<0.05) by AHP treatment. Scanning electron microscopy analysis showed that IDF had fluffy structure and wrinkled surface after AHP treatment. The results of X-ray diffraction indicated the crystal structure of IDF did not change after AHP treatment， but the diffraction intensity increased from 13.09% to 16.13% (P<0.05). Infrared spectroscopy indicated the breakage of some chemical bonds of IDF after AHP treatment， and the characteristic adsorption peaks weakened or disappeared. Thermogravimetric analysis showed that after AHP treatment， the peak pyrolysis temperature of IDF decreased， but the mass residue rate increased from 10.43% to 15.94% (P<0.05). Moreover， the water holding capacity， oil holding capacity， cholesterol adsorption capacity， Cu2+ adsorption capacity and cation exchange power of IDF were effectively enhanced (P<0.05) after AHP treatment， sodium nitrite adsorption capacity of did not change significantly (P>0.05)， while the expansion capacity was greatly reduced (P<0.05). These results suggested that AHP treatment can change the structure of lotus root residue IDF and improve its functional properties.

Abstract:A total of 10 protease-producing strains were isolated from homemade fermented seafoods， and were identified as Bacillus velezensis S1YBB， S1YB， Serratia marcescens S2DD， S2DB， C2Y3， M1B， C2J2， Micrococcus luteus C1Y1， Shewanella alga C2J1， and Enterococcus hirae M1R. The biological and enzymatic characteristics of S1YB， S2DB， C1Y1， C2J1， and M1R from different species with relatively higher enzyme activities were evaluated. The optimum growth temperature， pH and salinity of the strains were 37 ℃， 6.0， and 20 g/L， respectively. The optimum temperature and pH for the enzyme activities were 50 ℃ and 6.0-8.0， respectively. Relative enzyme activities of the strains were decreased under the treatment of Na+， K+， Ca2+， Fe2+， Fe3+， Zn2+， Cu2+ and ethylene diamine tetraacetic acid (EDTA) and in response to their concentrations. The results provided theoretical supports for exploring strains with excellent fermentation performance in seafood fermentation and controlling unexpected protease-producing strains in seafood fermentation processes.

Abstract:By analyzing the changes of Saccharomyces cerevisiae fortification on the microbial composition and volatile metabolites of Nong-flavour fermented grains， the disturbances of the microbial ecological network， volatile metabolites and the potential metabolic functions of the microbial community were explored. A strain of Saccharomyces cerevisiae Y1 isolated from nong-flavour fermented grains fermented was used to disturb the solid-state fermentation of fermented grains， and the composition of microorganisms and volatile metabolites were studied by high-throughput sequencing technology and headspace solid-phase microextraction-mass spectrometry technology， respectively. The random forest learning algorithm was used to calculate the biomarkers between the experimental group and the blank group， and the differences in the microbial ecological network between the experimental group and the blank group were analyzed based on the construction of a co-occurrence network model. PLS-DA analysis and Spearman correlation were used to analyze the differences of volatile flavor compounds， the correlation of differential metabolites and biomarkers， respectively. Finally， potential functional changes were analyzed by PICRUST2 functional prediction and pathway enrichment. The results showed that 5 bacteria and 15 fungi can be used as biomarkers to characterize the microbial composition of fermented grains disturbed by Saccharomyces cerevisiae， and also increased the complexity of the microbial ecological network. Meanwhile， the composition of volatile metabolites was altered， with 18 differential metabolites， and the content of some volatile metabolites was improved. The vast majority of biomarkers were significantly associated with differential metabolism. In addition， the perturbation effect of Saccharomyces cerevisiae resulted in 180 up-regulated genes and 46 down-regulated genes in the microbial community， most of which were related to the metabolism of substances. These results provide a basis for the application of Saccharomyces cerevisiae in Baijiu fermentation and the optimization of the fermentation process of fermented grains.

Abstract:To investigate the hypolipidemic function and regulation of gut microbiota of C57BL/6 mice on high-fat diet by aqueous extract of Wuniu Zao black tea. Thirty 8-week-old male C57BL/6 mice were randomly divided into three groups， namely the normal group (NC)， the high-fat group (MC) and the Wuniu Zao black tea aqueous extract group (referred to as the black tea group， WBT)， to establish a high-fat diet-induced obesity model in mice， and the black tea group was given a gavage dose set at 300 mg/kg tea aqueous extract. Routine indicators such as energy intake， body weight gain， organ index and Lee's index were recorded regularly in mice， and serum biochemical indicators such as glutamic aminotransferase (AST)， alanine aminotransferase (ALT)， total cholesterol (TC)， total triglyceride (TG)， low-density lipoprotein(LDL-C)， high-density lipoprotein(HDL-C) and glucose tolerance levels were measured， and HE-stained liver histopathological sections were observed. Real-time PCR was applied to detect the mRNA content of six genes such as SREBP1c， PAI-1， FAS， ACC1， SCD1 and CD36 in mouse liver tissues， and Western blot was used to study the expression levels of lipid-regulated proteins. 16S rDNA method was used to analyze the diversity and abundance of gut microbiota and its community structure. The results showed that compared with MC， WBT mice showed significant differences (P<0.05) in body weight (27.5 g)， liver index (3.78)， serum biochemical indexes (TC:4.31 mmol/L， TG:0.71 mmol/L， LDL-C:0.47 mmol/L， AST:74.44 U/L and ALT:23.93 U/L)， and increased but not statistically significant HDL-C levels(2.68 mmol/L)； the degree of liver lesions in mice improved. The mRNA expression levels of six genes， including SREBP1c， PAI-1， FAS， ACC1， SCD1 and CD36， were significantly different (P<0.05)； protein blotting showed that the expression levels of liver tissue-related proteins， such as SREBP1c， FAS and ACC1， were reduced in WBT mice， accompanied by increased phosphorylation of ACC1(p-ACC1) (P<0.05). The results of 16S rRNA gut microbiota analysis based on colonic feces showed that the relative abundance of Bacteroidetes (B) and Firmicutes (F) in the intestine of MC mice tended to decrease and increase significantly， respectively， and the ratio of the abundance of both flora(F/B) showed a significant increase； WBT improved the diversity and abundance of gut microbiota in mice by WBT improved the diversity and abundance of gut microbiota， especially the relative abundance of the Firmicutes phylum and the Bacteroidetes phylum， thus improving the disorder of gut microbiota induced by high-fat diet， and thus effectively regulating the normal operation of mouse lipid metabolic pathway. The results showed that the aqueous extract of Wuniu Zao black tea had the effect of regulating lipid metabolism and improving gut microbiota disorders in mice fed a high-fat diet of C57BL/6 mice.

Abstract:To explore the potential probiotic effect of an Enterocin Y3 producing strain of Enterococcus faecalis DH9003， about 15 healthy C57 male mice were intragastrically administered with sterile saline (control group， n=7) and E. faecalis DH9003 (treatment group， n=8). After 4 weeks， the feces of mice were collected to determine the effect of E. faecalis DH9003 on intestinal flora modification and metabolic function of mice. The results showed that E. faecalis DH9003 were colonized in large quantities in mice within 7 days after intragastric administration. The number of the strain increased slowly and became stable at 7-28 days. By observing the pathological characteristics of the intestinal and liver tissue sections of mice， the intake of E. faecalis DH9003 had a certain improvement effect on the intestinal mucosa barrier of mice， indicating that the strain made the intestinal mucosa of mice denser and longer. Meanwhile， the strain showed no pernicious influence on the livers of mice. The intragastric administration of E. faecalis DH9003 led to the different diversity of the treated group， and became the dominant species among different groups. The supplement of E. faecalis DH9003 had a certain regulatory effect on the bacterial community structure modification in the intestinal tract of mice， and the modification at the phylum level was the differences of relative abundance between Bacteroidetes and Firmicutes. A total of 254 differential metabolic substances were detected between control and treatment group， and 124 differential metabolic substances were up-regulated and 130 differential onces in turn were down-regulated. The enrichment analysis of KEGG pathway showed that the metabolic pathways with high levels of visibility included ABC transporter proteins and protein digestion and absorption pathways. In summary， E. faecalis DH9003 could be colonized in vivo and effect on intestinal flora and metabolic ability of the host in some degree.

Abstract:To study the antioxidant effect in vivo and the effect of alleviating visual fatigue of blueberry pulp， and analyze the correlation between the antioxidant function of blueberry pulp and the effect of improving visual fatigue. The protein content， superoxide dismutase (SOD) activity， catalase (CAT) activity and malondialdehyde (MDA) content of mice were determined by kit after 30 days of low， medium and high doses of blueberry pulp. A total of 40 volunteers aged 18-22 with visual fatigue symptoms were selected and randomly divided into control group and trial drinking group. The trial drinking group drank 2 bottles of blueberry pulp (100 mL/d) every day for consecutive 60 d. The results showed as follows: Compared with blank control group， the serum SOD activity of mice was significantly increased to 610.76 U/mg prot， while the serum MDA content was significantly decreased to 4.82 nmol/mg prot in the intake of 0.53 mL blueberry pulp (P<0.05)， and the intake of 0.21 mL blueberry pulp could significantly increase CAT activity in mice to 8.58 U/mg prot (P<0.05). The human body test showed that after drinking the blueberry juice for 60 d， the symptoms of visual fatigue and the duration of photopic vision were improved in the test group， and there was a significant difference in the male group (P<0.05). Result: Blueberry pulp has good antioxidant properties as well as good for relieving visual fatigue.

Abstract:6-Paradol nanoemulsions were prepared by ultrasonication method. Two emulsifiers (Tween 85 or lecithin) were used to optimize the preparation conditions by designing a three-factor， three-level orthogonal test using emulsion particle size and polydispersity index(PDI) as the criteria， and emulsifier dosage， ultrasonication time， ultrasonication power， and mass fraction of the core as the variables. The results showed that the optimal conditions for the preparation of emulsions using Tween 85 were: Emulsifier dosage of 1% Tween 85， ultrasonic power of 250 W， ultrasonic time of 15 min， and 6-paradol mass fraction of 0.1%. The optimal conditions for the preparation of emulsion using lecithin were: emulsifier dosage of 1% lecithin， ultrasonic power 350 W， ultrasonic time 15 min， and 6-paradol mass fraction of 0.2%. The produced 6-paradol nanoemulsions were of oil-in-water(O/W) type， and the particle sizes of the two emulsions were found to be(144.1 ± 3.76) nm and (241.4 ± 2.12) nm after repeated measurements， and the encapsulation rates of 6-paradol were found to be (96.5 ± 2.51) and (87.47 ± 1.84) %， respectively， in which the 6-paradol was encapsulated in a good way. Meanwhile， it was stored at 4， 25 ℃ for 35 d. As a result， 6-paradol nanoemulsion had a better storage stability in low temperature environment. The results of the experiment provide a certain technical reference for the encapsulation and protection of fat-soluble nutrients.

Abstract:In this study， pea protein-high methoxyl pectin (PP-HMP) composite particles was prepared by ultrasound， and investigated the effect of ultrasound on the physico-chemical properties of PP-HMP composite particles. Meanwhile， the structure properties of PP-HMP-US were characterized by fourier transform infrared spectroscopy (FTIR)， fluorescence spectroscopy， and transmission electron microscopy (TEM). The results showed that higher emulsifying activity and stability of pea protein-high methoxyl pectin by ultrasound (PP-HMP-US) were observed at 10 min， 5.43 W/cm3 and 15 ℃. Compared with PP-HMP， the turbidity of PP-HMP-US was decreased. Particle size， and PDI of PP-HMP-US was reduced from 1 453.26 nm and 0.34 to 541.44 nm and 0.27， respectively. According to FTIR and fluorescence spectroscopy results， HMP could significantly increased the relative content of β-turn and α-helix from 13.67% and 19.89% to 33.85% and 26.61%， respectively. The addition of HMP inhibited the aggregation of PP， and formed a tighter tertiary conformation. Proper ultrasound treatment of PP could make its β-sheet unfold to form α-helix， and enhance the interaction of PP and HMP. Meanwhile， the exposure of tryptophan residues of PP decreased after ultrasound treatment. In addition， TEM results showed that ultrasound enhanced HMP embedded in PP spherical structure to obtain PP-HMP-US composite particles with more regular and ordered structure. The results provided a theoretical basis for the utilization of pea protein in food processing.

Abstract:Objective: This work was aimed to analysis the influence of steaming processing on the extraction， physiochemical properties， and digestion properties of sweet potato soluble dietary fiber(SDF). Methods: The response surface methodology and desirability function were conducted to optimize the solid-liquid ratio， extract temperature， and extract time of sweet potato SDF extraction for higher yield and total sugar content. SDF from steamed sweet potato (SDF-S) and from fresh sweet potato (SDF-F) were extracted by the optimized parameters. The yield， polysaccharide composition， and dietary fiber content， as well as water holding capability and oil holding capability， were measured to compare the differences of two SDF. Besides， simulated digestion in vitro was performed to assess the digestion properties. Results: The optimized parameters were 1∶16 of solid-liquid ration， 40 ℃ of extraction temperature， and 40 min extraction time. The SDF-S showed significantly higher yield [(6.13±0.25%) vs (2.89±0.18)%]， neutral polysaccharide content [(59.31±0.73)% vs(46.83±0.63)%]， acidic polysaccharide content [(25.36±0.48)% vs (9.60±0.14)%]， dietary fiber content [(54.71±6.70)% vs (35.69±3.25)%]， water holding capability [(4.60±0.31) g/g vs (3.27±0.21) g/g] and oil holding capability [(3.30±0.40) g/g vs (1.82±0.28) g/g] than SDF-F (P＜0.05)， while the SDF-F showed better resistance to digestion than SDF-S. Conclusion: Steaming processing improved the accessibility of sweet potato SDF but weakened its resistance to digestion.

Abstract:To explore the enrichment process of monounsaturated fatty acids from fish oil， this study used anchovy oil as raw material and purified POA using a composite solvent low-temperature crystallization method. Compared to a single solvent， composite solvents exhibited superior performance. In order to optimize the process， single-factor experiments were conducted， considering the type and volume ratio of the solvents， massratio of fish oil to solvent， crystallization temperature， and crystallization time， with POA content and yield as indicators. The optimal process conditions were determined as a volume ratio of acetone to acetonitrile of 1∶10， a mass ratio of fish oil to solvent of 1∶6， a crystallization temperature of -60 ℃， a crystallization time of 6 h， and the POA content was analyzed as (29.75±0.53)% in the obtained mixed fatty acids. Further scaling up experiments were conducted to increase the yield to around 50%， with a total unsaturated fatty acid content of over 79%. This serves as a valuable reference for the enrichment process of ω-7 monounsaturated fatty acids.

Abstract:To explore the effects of calcium ion， pectin and NFC citrus juice addition on the sensory and nutritional quality of fruit juice-type canned yellow peach， the processing technology of juice-type canned yellow peach was optimized by using Dangshan yellow peach NJ83 as raw material and the combination of yellow peach pulp and NFC citrus juice through evaluation indexes such as chromaticity， texture characteristics and sensory level. The results of visual analysis and variance analysis showed that the adding amount of calcium ion had the greatest impact on the sensory quality of juice-type canned yellow peach， followed by NFC orange juice， and the last was pectin. The optimal process was as follows: The mass fraction of calcium ion was 0.4%， the mass fraction of pectin was 0.35%， the mass fraction of NFC fruit juice was 8%. In the final product， fruit juice was transparent， the pulp was golden yellow， the color was uniform， the block shape was complete without burrs， the taste was sweet and sour， the hardness was moderate. HPLC was further used to detect the flavonoids in canned foods under the optimal process and found that the content of hesperidin in juice-type canned yellow peach was 70.665 mg/kg， which was 22 times higher than 3.149 mg/kg in water-type. The content of narirutin (9.193 mg/kg) and didymin (6.807 mg/kg) were 161 times and 33 times higher in juice-type can than in water-type can， respectively. Therefore， juice-type canned yellow peach is a new canned product with both taste and nutrition.

Abstract:In order to investigate the effect of debranching treatment on the structural characteristics and physicochemical properties of maize starch-chitosan complex. In this study， maize starch (MS) was used as raw material， pullulanase was used for enzymatic debranching， debranched maize starch-chitosan complex(DBS-CS) was prepared by mixing debranched starch(DBS) and chitosan(CS) solution. The microstructure， particle size distribution， crystalline structure， molecular short-range ordered structure and rheological properties of the complex were determined. Results showed that the more chitosan attached to the particle surface of debranched maize starch-chitosan complex， the tighter the binding force between particles and the larger the average particle size of the complex， and improved thermal stability. The crystallinity of DBS and DBS-CS decreased after debranched， the crystal structure changed from A type to B type. The FT-IR spectrums of and 1H NMR spectroscopy showed that starch and chitosan could form complex， and the composite of debranched maize starch and chitosan had better effect. The debranched starch-chitosan complex had typical weak gel dynamic rheological behavior and pseudoplastic shear thinning behavior. This study provides a theoretical basis for obtaining a new type of green security complex modified starch.

Abstract:In order to improve the drying rate of corn and clarify the effect of microwave intermittent drying on the starch in corn， this paper took 'Jinongyu 719' as the research object， and compared the effects of natural drying and microwave intermittent drying on the processing and structural properties of corn starch under different microwave power densities. The results showed that compared with natural dried corn， the properties of corn starch changed significantly after microwave drying. When the microwave power density was in the range of 0.9-3.6 W/g， the peak viscosity and solubility of corn starch increased first and then decreased. When the microwave power density was 1.8 W/g， the peak viscosity and solubility of starch were the highest. The results of static rheology showed that the starch gel of corn was pseudoplastic fluid after natural drying and microwave drying. The results of dynamic rheology showed that when the microwave power was in the range of 0.9-1.8 W/g， the viscoelasticity of corn starch gel could be significantly improved by microwave. When the microwave power density was 1.8 W/g， the viscoelasticity of starch gel was the best. When the microwave power density was higher than 1.8 W/g， the hardness of corn starch gel increased significantly. After microwave drying， the swelling degree， enthalpy value and order degree of corn starch decreased， and the particle size increased. The results showed that the characteristics of corn starch dried with microwave power density of 1.8 W/g， microwave action time of 2 min and soaking time of 4 min were the best.

Abstract:In order to improve the drying process of oat noodles， the effects of temperature， relative humidity and addition amount of oat on its quality were studied. Wheat flour and oat powder were used as raw materials to prepare oat noodles with different content of oat (0， 10%， 20%， 30%)， which were dried at different temperatures (40， 50， 60 ℃) and relative humidity (55%， 65%， 75%). The color， bending resistance， cooking quality， texture quality， acidity， fatty acid value， β-glucan content， microstructure， and sensory quality were measured， and analyzed the effects of different temperature， relative humidity and different amount of oat on the quality of oat noodle. The results showed that the dried noodles had lower b value， longer breaking distance， lower acidity， and fatty acid content when dried at 40 ℃ (P < 0.05). When the relative humidity was 75%， the b value， bending strength， breaking distance， acidity and fatty acid content of the noodles were higher (P < 0.05). When the addition amount of oat flour was 30%， the L value was lower， the a value was higher， the bending strength breaking distance was smaller， and the acidity， fatty acid and β-glucan contents were higher (P < 0.05). The temperature of 45 ℃ and relative humidity of 75% were reasonable drying process of oat noodles. Drying at low temperature and high humidity (40 ℃/75%) can improve the color， cooking， and texture quality of oat noodles， the microstructure is compact and the sensory score is good. It can be used for drying oat noodles.

Abstract:In this paper， Weissella confusa (WC) and Lactobacillus plantarum (LP) were used to ferment sourdough with yeast alone and together， compared with the sourdough fermented with yeast alone (CK) to discuss the change of lactic acid bacteria number and organic acid content of different sourdoughs. And to discuss the effects of different sourdoughs to steamed bread dough on water distribution， rheological properties and to steamed bread on quality and flavor. The results of the study found that the pH of the sourdough fermented with lactic acid bacteria remained stable after 24 h. The bacterial number of WC+LP group reached the highest at 24 h， which was 9.34 lg(CFU/g sourdough). After 24 h fermentation， the lactic acid content in LP group was 7.75 mg/g sourdough， and the acetic acid content in LP+WC group was 0.49 mg/g sourdough. The T2 relaxation time of steamed bread dough with sourdough was 235.43 ms and of CK group was 252.35 ms， The T2 relaxation time of these groups was shorter than that without sourdough which was 289.94 ms， and the viscoelasticity of steamed bread dough decreased. The addition of sourdough increased specific volume， reduced the hardness and improved the elasticity of steamed bread， the maximum specific volume of the LP+WC group was 2.17 mL/g， which was 20.56% higher than that of ordinary yeast bread， the hardness of the LP+WC group was reduced by 25.89% and the elasticity of the LP+WC group increased by 4.5% compared with that of ordinary dry yeast bread (OSB). GC-MS analysis showed that 35 flavor substances were detected in LP+WC group， with the largest variety. The results showed that the quality and flavor of steamed bread could be improved by the compound fermented sourdough with Weissella confusa and Lactobacillus plantarum， which laid a theoretical foundation for the next use of related bacteria to ferment sourdough.

Abstract:To decipher the role of jasmonate in chemical elicitor L-glutamate induced resistance to pathogens， tomatoes were treated with 0.1 mg/mL L-glutamate and/or 0.1 mmol/L methyl jasmonate. After inoculating with Alternaria alternata spore suspension， disease incidence of fruit was observed. The effect of L-glutamate on jasmonate biosynthesis and signaling pathways were analyzed by reverse transcription quantitative real-time polymerase chain reaction at the transcriptional level. The results showed that the disease incidence decreased by 35% in L-glutamate treatment compared with the control， while there was no significant difference between L-glutamate and the control in methyl jasmonate group. Concurrently， allene oxide synthase， allene oxide cyclase， coronatine insensitive 1， transcription factor MYC2 and protease inhibitor PI-II were down-regulated by L-glutamate， accompanied by higher expression level of the negative regulator JAZ1. Collectively， the inhibition of JA pathway might be involved in L-glutamate induced resistance to Alternaria alternata in tomato fruit. These findings provided a better understanding for L-glutamate mediated resistance， leading to more sufficient theoretical basis for its commercial application.

Abstract:In order to reduce the postharvest decay rate of Prunus crispiflora， slow down the ripening and senescence of fruits， and prolong the shelf life， three kinds of preservation treatments， including 2% calcium chloride soaking， polyvinyl alcohol coating， 2% calcium chloride soaking + polyvinyl alcohol coating， and 2% calcium chloride soaking + polyvinyl alcohol coating film， were compared with the activities of titratable acid (TA)， soluble solids (SSC)， respiratory intensity， hardness， malondialdehyde content (MDA)， polygalacturonidase (PG)， peroxidase (POD)， and polyphenol oxidase (PPO) activities of Prunus crispi red plum in 4 °C storage environment. Effect of biochemical indicators. The results showed that the composite preservation method of 2% calcium chloride soaking + polyvinyl alcohol coating film effectively delayed the decrease of TA content and maintained it at more than 0.8%， slowed down the increase of SSC content (P<0.05)， kept it at about 16 °Brix， kept the fruit hardness above 14.11 N， and maintained the flavor and taste of crisp red plum well， and maintained the respiratory intensity at 4.9758~19.9898 mg/h·kg. The respiration intensity of P. crispiflora was inhibited (P<0.05)， and the PG activity gradually increased to 70.72 μg/h·g FW on the 30th day， significantly inhibited the PG activity (P<0.05)， decreased the accumulation of MDA， and significantly inhibited the PPO activity (P<0.05) from 0.2 U/g FW to 0.058 U/g FW in 12~24 days， delaying the ripening and senescence of the fruit. After harvest， the crispy red plum treated with 2% calcium chloride combined with polyvinyl alcohol coating film had the best preservation effect under the condition of 4 °C refrigeration， which could effectively delay the aging and deterioration of crispy red plum.

Abstract:In this study， the conditions of low-temperature plasma-coupled slightly acidic electrolyzed water for salmon sterilization were optimized through single factor and Box-Behnken response surface tests. In addition， physicochemical indicators like total viable count (TVC)， pH value， total volatile base nitrogen (TVBN)， thiobarbituric acid reactive substances (TBARS)， carbonyl content， and color were analyzed to compare the preservation effects of plasma-activated water (PAW)， slightly acidic electrolyzed water (SAEW) and cold plasma application combination with slightly acidic electrolyzed water (PASW) on salmon at 4 ℃. The results showed that the optimal condition for sterilization was slow temperature plasma activation time - 5 min， the power - 320 W， immersion time - 20 min， effective chlorine concentration - 50 mg/mL， and solid-liquid ratio - 1 ∶ 6. The abovementioned three treatment groups could all prolong the storage time of salmon， but low-temperature plasma coupled with slightly acidic electrolyzed water was more conducive to alleviating lipid and protein oxidation. This study provides a new idea for the preservation of aquatic products.

Abstract:In order to study the effects of different storage temperatures (4， 25 ℃ and 37 ℃) on β-cyclodextrin stabilized Antarctic krill oil Pickering emulsion and determine the shelf life. Firstly， the Antarctic krill oil Pickering emulsion was prepared by high-speed shearing method， and the particle size and potential of the emulsion were 13.64 μm， -38.14 mV， and the centrifugal stability was 85.34%. And then， the effects of different storage temperatures on emulsions were studied by the appearance and microscopic changes of emulsions， particle size， ζ-potential， centrifugal stability， creaming index， POV and TBARS. The results indicated that higher temperature resulted in more acute Brownian movement， which increased the possibility of coalescence and the shortened the time required for emulsion instability. The shelf life of the emulsion under 4， 25 ℃ and 37 ℃ was 28， 16 d and 8 d， respectively. This study provides a reference for the development and utilization of Antarctic krill resources.

Abstract:The combination of electronic nose and headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry was used to analyse the differences in volatiles in soybean oil from three processing methods， which was extracted oil， hot pressed oil and cold pressed oil， respectively. The results showed that 86 volatile compounds were detected in the three soybean oil samples， 53 of them in the extracted oil， 54 of them in the hot pressed oil and 45 in the cold pressed oil. The main volatile components included aldehydes， alcohols， ketones， acids， esters， terpenes， heterocycles(furans and pyrazines) and hydrocarbons and so on. 24 volatile components were identical in the three types of soybean oil. The principal component analysis and hierarchical cluster analysis indicated that the processing method had a big impact on the flavour of soybean oil. By odour activity value(OAV) technique， there were 15 key flavour compounds detected in the extracted oil， dominated by substances such as 3-nonen-2-one， resulting in a berry flavour in the extracted oil. Moreover， 16 key flavour compounds detected in hot pressed oil， which reflected distinctive baking flavour due to heterocyclic compounds such as 2，5-dimethylpyrazine. However， 12 key flavour compounds were detected in the cold pressed oil， dominated by aldehydes such as (E，E)-2，4-heptadienal， which gave natural oil flavour of the cold pressed oil. The results of the partial least squares regression analysis showed a good correlation between the electronic nose and the GC-MS results.

Abstract:Objective: The purpose of this study was to establish the fingerprint of volatile components of Wuyi Hongqu Huangjiu base wine， which could be used to distinguish the age of base wine. Methods: The volatile components in Wuyi Hongqu Huangjiu with different aging time were analyzed by headspace solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS)， and the key components related to the year were determined by orthogonal partial least squares discriminant analysis (OPLS-DA) and Spearman correlation analysis， which were used to construct the characteristic fingerprint of the year base wine. Results: A total of 122 volatile components were detected and identified from Wuyi Hongqu Huangjiu in different years， and 20 were significantly correlated with aging time (r>0.5 or r < -0.5). Among them， N-benzoyl glycine ethyl ester， 6-heptanoic acid ethyl ester， acetic acid-2-ethyl phenyl ester， 3- (2-furanyl) - 2-acrolein， ethyl phenylacetate were significantly positively correlated with aging time， 2-furan methanol， caprylic acid Ethyl heptanate and other 12 species were negatively correlated with the aging time of Wuyi Hongqu Huangjiu. Based on the selected 20 year characteristic volatile substances， the fingerprint of Wuyi Hongqu Huangjiu base wine was constructed. According to the OPLS-DA analysis of aroma components and the fingerprint data information， the samples of Wuyi Hongqu base wine from 2 to 15 years were divided into three categories: Green wine (2-4 years)， medium wine (5-9 years) and old wine (10-15 years)， The reliability of the established map was verified by secondary sampling analysis. Conclusion: The fingerprint of volatile components constructed by GC-MS technology could provide basic data support for the quality evaluation and identification of wine age of Wuyi Hongqu Huangjiu.

Abstract:Objective: To study the chemical constituents of Gelidium amansii and lay a foundation for the research and development of functional food of Gelidium amansii. Methods: TLC and LC-MS were used to analyze the richness of chemical components in the ethanol extract of Gelidium amansii. The ethanol extract of Gelidium amansii was separated and purified by silica gel column and HPLC， and the structure of compounds were determined by GC-MS， NMR， and combined with the data reported in the literature. The antioxidant activity of some compounds was determined. Results: TLC and LC-MS analysis showed that the ethanol extract of Gelidium amansii was rich in secondary metabolites， and it was likely to be sterols. 29 compounds (5 sterols) were identified from the ethanol extract by GC-MS. Among them， palmitic acid (46.76%)， ethyl palmitate (13.82%)， cholesterol (7.20%)， 4，6-cholestadien-3beta ol (4.99%) were the four compounds with the highest content. After chromatographic separation and NMR identification， 9 compounds were obtained， which were cholesterol (1)， 1，2-diol phytoene (2)， pagosterol C (3)， 6-hydroxy- cholest-4-en-3-one (4)， cholest-5-en-7-one (5)， cholest-5-ene-3β， 7α diol (6)， cholest-5-ene-3β， 7β diol (7)， cholest-4-en-6-one (8)， 3-hydroxyethyl-2-methyl-maleimide (9). Compound 7 has the strongest ability to scavenge DPPH and ABTS free radical with IC50 values of 0.18 mg/mL and 12.2 μg/mL， respectively. Conclusion: In this paper， the ethanol extract of Gelidium amansii were systematically studied for the first time. Compounds 3， 8 and 9 were new natural products. Some sterols showed good antioxidant activity.

Abstract:To determine the correlation between dominant microorganisms and physicochemical characteristics of pickle brine. Analysis of the correlation between physicochemical properties and microbial communities was revealed， while the microbial community structure was investigated using high-throughput sequencing technology. The results showed that: The total acid content of pickle brine was 3.00-18.90 g/kg， the pH value was 3.27-4.71， the salt content was 11.00-15.50 g/100 g， and 7 kinds of organic acids including oxalic acid， malic acid， succinic acid and lactic acid were detected. The dominant microbial phylums include Firmicutes and Ascomycota， accounting for more than 99.00% of the total. The dominant bacterial genera were Lactobacillus and Pediococcus. The dominant fungal were Pichia， Kazachstania and Debaryomyces. The correlation analysis showed that Lactobacillus had a significant positive correlation with lactic acid (P<0.05) and acetic acid (P<0.01)， and Pediococcus had a significant positive correlation with malic acid (P<0.01). In summary， Lactobacillus spp. and Pediococcus were the dominant microorganisms in the pickle brine. This provided a reference for the selection and breeding of efficient fermentation strains of pickle brine and industrialization of pickles.

Abstract:Empty bud Carya cathayensis refer to Carya cathayensis with no seed kernels or stunted development， which will seriously affect the product quality of Carya cathayensis. To achieve rapid and non-destructive identification of empty bud Carya cathayensises， two NIR detection devices were used to collect spectra of shelled Carya cathayensises samples in the wavelength range of 200-1 160 nm. Eight different preprocessing methods wers used for spectral preprocessing， and competitive adaptive reweighted sampling (CARS) was used to select the sensitive wave length variables of empty bud Carya cathayensises. Finally， linear discriminant analysis (LDA)， quadratic discriminant analysis (QDA)， and mahalanobis discriminant analysis (MDA) were applied to establish the classification models of empty bud and normal Carya cathayensises. The results showed that the performance of the classification models of empty bud Carya cathayensis established using detection device 1 were better than that of the detection device 2. The classification models established after multivariate scattering correction (MSC) pretreatment showed the best recognition results. The specificity， sensitivity and correctness of LDA， QDA， and MDA models were all 1， which were better than the classification models established by other preprocessing methods. After CARS variable screening， the number of spectral variables used for modeling was significantly reduced， effectively simplifying the classification model. However， the model performance was still on par with that of the full-band model. This paper provides a feasible method for the rapid nondestructive identification of empty bud Carya cathayensis by near-infrared spectroscopy combined with chemometric methods.

Abstract:As a common antibiotic， tetracycline(TC) is extensively used in the prevention and treatment bacterial diseases in animals and is also used as a feed additive to promote the growth of animals. In this paper， a fluorescence quenching method based on nitrogen doped carbon quantum dots(N-CQDs) derived from pineapple peel was established for the rapid detection of TC. The blue fluorescent N-CQDs with high quantum yield were prepared by the hydrothermal method using pineapple peel and diethylenetriamine as precursors. The structure of N-CQDs was characterized by transmission electron microscope， fourier infrared spectroscopy and X-ray photoelectron spectroscopy. The results showed that the average particle size of N-CQDs was about 3.53 nm， which was mainly composed of C， N and O， and the surface has oxygen-containing and nitrogen-containing groups. The fluorescence of N-CQDs was effectively quenched by static quenching and internal filtering effect. Under the optimal experimental conditions， the method had good linearity within 0.3-40 μg/mL， and the detection limit was calculated to be 89.26 μg/L. Moreover， the detection method has been applied to the determination of TC in pork， the recovery rate was 98.40%-106.02%. The results showed that the detection method could be applied to the rapid determination of TC in pork.

Abstract:To distinguish the diflerences in the types and contents of flavonol glycoside in green tea from 6 production areas， and explore the feasibility of flavonol glycoside for geographical traceability of green tea. In this study， the qualitative identification of flavonol glycosides by ultrahigh performance liquid chromatography-quadrupole-electrostatic field orbitrap high resolution mass spectrometry(UPLC-Q-Orbitrap HRMS)， and a quantitative method of flavonol glycosides in green tea was established based on ultra high performance liquid chromatography -tandem triple quadrupole mass spectrometry (UPLC-MS/MS). The results showed that a total of 21 kinds of flavonol glycosides were positively identified in green tea， including 5 myricetin glycosides， 8 quercetin glycosides and 8 kaempferol glycosides. The quantitative analysis showed that the content of flavonol glycosides varied from different producing area in green tea， in which the content of K-glu-rha-glu was the highest， accounting for 33.1%-57.8% of 21 kinds of flavonol glycosides， followed with the kaempferol glycoside， while content of myricetin glycoside was the lowest. By analyzing the differences and correlations of flavonol glycosides in green tea from 6 production areas indicate that they can be used for geographical traceability of tea. The green teas from different producing areas could be effectively distinguished by PCA. The precision rate was 100.0% for BP-ANN recognition， and 2 kinds of compound markers for flavonol glycoside were acquired with 100% importance (P<0.05). The predictive ability of PLS-DA model was 78.2%， and 8 biomarkers (VIP>1) were screened out. The entirety precision rate was 100% by LSD model， and the precision rate of cross validation result was 100%. The results of this study may provide scientific basis for the study of geographical traceability and chemical classification of tea.

Abstract:3D printing technology achieves rapid molding of specific structural objects by adding materials layer by layer， allowing personalization of the composition of raw materials and the spatial structure of finished products according to demand， which has broad development potential in the food industry. Most food ingredients are not printable， which restricts the sources and types of food ingredients used for 3D printing and limits the application scales of 3D printing technology in the food industry. Plant-based nanocellulose is widely sourced and has excellent mechanical and rheological properties that enhance the printability of materials， making it an ideal ingredient for 3D printing. Defining the functional characteristics of plant-based nanocellulose， the properties of prepared 3D printing inks， and the application status in food 3D printing is particularly important to take adequate advantage of emerging processing technologies and food ingredients. This paper introduced the structural characteristics of plant-based nanocellulose and its functional properties compatible with 3D printing， including high mechanical strength， convenient surface modification， suitability for printing rheological properties， and favorable biosafety， analyzed the properties and uses of both types of two types of plant-based nanocellulose printing inks， hydrogels and emulsions， summarized its application status in food additives， food packaging， food freshness indicators， functional substance carrier， provided an outlook for the future of preparing emerging functional foods and smart food packaging， and made a prospect in order to provide a referential for future development.

Abstract:Food allergy (FA) is a major food safety problem that has plagued human health for a long time because of its multiple causes and complex and comprehensive allergy mechanism. Active polysaccharides have attracted extensive attention in the fields of food， medicine and biology because of their wide sources and biological activities such as immune regulation， anti-cancer and anti-tumor. Taking the action mechanism of food allergy as the starting point， this paper summarized the research on the correlation between food allergy and active polysaccharide， and analyzed the action pathway of active polysaccharide in regulating food allergy， in order to provide reference for the development of hypoallergenic food， medicine and feed.

Abstract:As one of the six major nutrients in the human body， protein is widely present in various foods， while polyphenols are abundant in plants as secondary metabolites. Proteins and polyphenols produce 'protein-polyphenol complexes' through covalent and non-covalent interactions， which mostly occur spontaneously in food and significantly affect the functional properties and quality of food. In this paper， the formation mechanism of protein-polyphenol complexes and the modern analysis and detection techniques and methods to characterize the interaction of the complexes were reviewed. Effects of protein-polyphenol complexes on their biological activities and their potential applications in emulsions， films， and delivery systems. The purpose was to provide a theoretical basis for the in-depth study of protein-polyphenol complexes， and to provide new ideas for the high-quality utilization and product development of proteins and polyphenols.

Abstract:With people's quality of life improves， so does their concern for disease and health. Instead of focusing on medical devices and pharmaceutical ingredients for the treatment of disease， people are gradually becoming more aware of emerging substances， ingredients or processed products that play a preventive， ameliorative or supportive role in mitigation. The role of these substances in the body is more focused on the maintenance of physiological functions or the promotion of health through regular external intake. The basic requirement for externally ingestible substances is safety of consumption， and the new labels of no side effects， variety， diversity， efficiency and convenience will be of interest to people in the future. Regular intake of probiotic products with safety certification is considered a safer and more common way to improve human health and alleviate diseases， while the low survival rate of probiotics and the high requirements for their functioning make them difficult to prepare on a large scale， to transport and store for long periods of time， and to ensure their action characteristics. Until now， various preparation and storage methods to ensure the high activity of probiotics have been continuously studied. In recent years， along with the in-depth research on probiotics， it has been found that postbiotics obtained from probiotics through different preparation methods can also have a positive effect on the organism， and have the characteristics of stability and convenient storage and transportation that probiotic products do not have， which may become a new direction to improve the organism's condition or enhance the function of the organism in the future. This paper summarized the various functional effects of postbiotics on the body and the applications of their related products in various fields.

Abstract:The mechanism of food oral processing and taste perception is a hot topic in the field of food nutrition and health in recent years. It is mainly based on the interaction between food and oral cavity， and uses interdisciplinary methods to study the changes in the structure and physicochemical properties of food during oral processing， as well as the oral perception and a series of physiological reactions caused by it. Saliva is the first body fluid of mammals contacting with food when eating. It is a clear， slightly acidic， viscous oral secretion secreted by three pairs of large salivary glands (parotid gland， submandibular gland and sublingual gland) and hundreds of scattered small salivary glands. Saliva is composed of water， a variety of inorganic substances and organic active protein molecules， and has a variety of important physiological functions. This paper focused on the interaction between saliva secretion and basic taste including sour， sweet， bitter， salty， umami， and generalized taste including fatty， pungent， spicy， and discussed in detail the relationship between saliva secretion and these taste perception， and summarized the effects of saliva in various taste perception. It will provide a theoretical basis for further study on the physiological correlation between saliva composition and taste perception.

Abstract:In recent years， with the improvement of people's living standards， the enhancement of health awareness and the acceleration of the pace of life， fresh-cut fruits and vegetables are increasingly favored by consumers due to its characteristics of convenient， safe， nutritious and fresh. However， cutting causes fruit and vegetable suffer irreparable mechanical damage， which may active its own defense system to synthesize phenolic substance secondary metabolites in order to resist and repair mechanical damage and enhance the antioxidant activity of fresh-cut fruits and vegetables. The pretreatment fresh-cutting operation improved the antioxidant and health benefits of fruits and vegetables has received widespread attention from postharvest scholars. In particular， it has the important progress on improving the potential nutritional value of fresh-cut fruits and vegetables based on physiological and biochemical studies on the biosynthesis mechanism of phenolic substances. Collectively， this paper reviewed the biosynthetic mechanism of phenolic substances and their antioxidant activity in fresh-cut fruits and vegetables， which aimed to provide a theoretical basis for elucidating that fresh-cut fruits and vegetables， as pre-processed products， produced more phenols and further improved the antioxidant activity of fresh fruits and vegetables. Meanwhile， this paper will provide new insights into the method that can effectively improve the phenolic substances content and antioxidant activity in fresh-cut fruits and vegetables.

Abstract:Anthocyanins are the main phenolic active components in blueberry， which have attracted much attention due to their excellent antioxidant， anti-inflammatory， anti-tumor and eye protection functions. However， anthocyanins in blueberry are easily affected by light， oxygen， pH value， metal ions and other factors， and their absorption and utilization rate are low in the human body， which limits their application. This review summarized the functional activities， extraction and purification methods， and stabilization technology of anthocyanins in blueberry， and hope to provide reference for the application of anthocyanins in food industry.

Abstract:Freezing is one of the convenient ways for the long-term preservation of fruits. However， the ice crystals produced in the freezing process tend to damage the cell structure， resulting in the loss of juice during thawing. Thus， the quality of fruits after thawing is seriously affected. Three methods could be used to optimize the quality of frozen fruits: Using osmotic dehydration， increasing the freezing rate， optimizing the thawing process. In this study， the new techniques used in fruit freezing and thawing were summarized， such as the osmotic dehydration protection， high-pressure， ultrasound， pulse electric field， microwave and magnetic field. The principles， applications， advantages and disadvantages were compared. This article provided new ideas for the development of fruit freezing and thawing.

Abstract:As people pay more and more attention to healthy diet， fruit and vegetable products have attracted much attention as an important source of nutrition. However， the preservation of fruits and vegetables has always been a difficult problem. Traditional fruit and vegetable preservatives often rely on chemical substances， which not only improve the preservation effect， but also bring potential risks and adverse effects. Therefore， the development of green and effective antibacterial agents in the production and distribution chain of fruits and vegetables has become a research hotspot. In recent years， the use of lactic acid bacteria to slow down fruit and vegetable spoilage has attracted a great deal of interest. They can slow down fruit and vegetable spoilage without significant adverse effects， so the potential of lactic acid bacteria as preservatives in fruits and vegetables is enormous. However， the inhibition mechanism of lactic acid bacteria is not well studied， and the number of lactic acid bacteria or their metabolites approved by regulatory agencies and widely available for commercial use is still small， leading to their imperfect application in fruit and vegetable preservation and storage. This paper reviewed the mechanism of lactic acid bacteria inhibition， the current status of application， and the potential advantages and limitations in the inhibition of spoilage bacteria. The research progress of lactic acid bacteria as bacterial inhibitors in fruit and vegetable products in recent years was summarized， and the development direction of lactic acid bacteria was prospected in order to provide theoretical basis for the application of lactic acid bacteria in fruit and vegetable preservation.

Abstract:Carotenoids， mainly found in dark fruits and vegetables， have biological activity functions such as anti-inflammatory and antioxidant， can strengthen the human immune system， help fight off various viruses， including SARS-CoV2 and other viruses. It is also a natural food colorant and natural antioxidant， which play an important role in protecting human health and industrial development. The applications of carotenoids in food are hindered by its poor chemical instability and low oral bioavailability. For this reason， delivery systems have been developed to solve the above problems. This review gave a briefly introduction to the metabolic process and influencing factors of bioavailability of carotenoids with special focuses on the research progress of carotenoid delivery systems which aimed to provide a reference for the functional application of carotenoids in food.

Abstract:Aquatic products are favored by consumers because of their delicious taste and rich nutrition， which belong to the allergic food recognized by the Food and Agriculture Organization of the United Nations and the World Health Organization， and they may be contaminated by foreign allergens during processing， transportation and storage， resulting in increasingly serious food safety problems caused by aquatic food allergy， which seriously restricts the development of the aquatic industry. Therefore， identifying the allergens in aquatic food and using appropriate detection techniques to detect and monitor them are conducive to preventing the occurrence of aquatic food allergies and diseases. In this paper， the main allergens in aquatic food， as well as the research progress of nucleic acid detection technology based on gene level， immunoassay technology based on protein level and mass spectrometry detection technology were summarized， which provided a theoretical basis for enriching the comprehensive understanding of aquatic allergens and their detection methods.

Abstract:Fish oil has a wide range of scientific research and application value because it is rich in polyunsaturated fatty acids needed by human body. This article focused on its n-3 PUFA enrichment process， steady state technology and biological activity， expounded the advantages and disadvantages of different methods， analyzed the feasibility of industrial production， and prospected the future development trend of fish oil industry， in order to provide a theoretical basis for the rational， healthy and sustainable development of fish oil resources.

Abstract:The momentum of central kitchen development is advancing rapidly， but also facing consumers with more diversified consumer demand and higher quality requirements. This paper summarized the central kitchen meat products in heat processing， storage and transportation， the change of product taste material， aimed to keep the central kitchen production and transportation chain on the good taste， ensurde the overall consumption experience of the central kitchen meat products， expanded the consumer market， so as to maximize the product quality and economic benefits， promote the central kitchen industry scale， standardized development.

Abstract:Double top-class construction and rural vitalization strategy have put forward new goals and challenges for the reform and innovation of higher education. It is urgent to cultivate high-level applied talents of food major who will lead the development of the new era. According to the new requirements of higher education reform， the construction advantages of first-class disciplines， the planning for double first-class university， and the standards of professional certification， this paper explored the construction of the training mode of professional degree postgraduates in food specialty. Furthermore， based on the current shortage of professional postgraduate talents training， it was put forward that ‘taking innovation as a breakthrough and agriculture processing technology as a foundation’ was an important embodiment of food professional degree postgraduate training under the promotion of double top-class construction and rural vitalization strategy. Meanwhile， the training mode of food professional postgraduate of ‘one mainstay， three wings， two in one integration’ and ‘platform combining four modernizations’ were constructed. The training mode can effectively improve the comprehensive quality， practical ability， and innovation ability of professional degree postgraduates. It is of great significance to promote the connotative and high-quality training of professional degree postgraduates.