Abstract:With the widespread recognition of the health benefits of probiotic lactic acid bacteria， the probiotic industry has ushered in a golden period of prosperity. Nevertheless， the development of China's probiotics industry is lagged by lack of independent intellectual property rights for probiotic strains and outdated screening and industrialization technologies. At present， China mainly relies on traditional pure culture techniques for lactic acid bacteria isolation， which is time-consuming， labor-intensive， and has limited accuracy. However， in recent years， the rise of high-throughput sequencing and artificial intelligence technology has opened a new chapter in the screening of probiotic lactic acid bacteria. Based on genome Big Data and artificial intelligence， researchers have developed precise isolation and identification technology for lactic acid bacteria， significantly improving the screening speed and accuracy， and also promoting the industrialization of probiotics. This article will comprehensively review the precise isolation and industrialization technology of probiotic lactic acid bacteria based on artificial intelligence， and further explore the development trend of China's probiotics industry.

Abstract:Phosvitin phosphopeptides (PPP) with high calcium binding capacity were prepared by a combination of high-temperature and low-pressure treatment， trypsin and thermophilic protease complex digestion. The optimum conditions for the preparation of PPP-Ca were determined to be pH 9.5 and a peptide-to-calcium mass ratio of 7:1. 97% calcium chelation was achieved under these conditions and PPP-Ca showed excellent stability in simulated gastrointestinal digestion. The monolayer model of Caco-2 cells was used to verify the calcium transport of PPP-Ca in vitro. The Caco-2 cell model was validated by cell morphology， electrical resistance and sodium fluorescein permeation， and MTT results showed that PPP-Ca exhibited low toxic effects on Caco-2 cells. The effects of PPP-Ca and PPP on the mass concentration of calcium ions transported and the activity of alkaline phosphatase (AKP) in Caco-2 cells were investigated， and the relative expression of CalbindinD9K m RNA was determined by RT-PCR. The results showed that PPP and PPP-Ca significantly increased AKP activity， increased calcium transport from (3.06±0.08) μg to (5.66±0.62) μg， and increased CalbindinD9K m RNA expression by 2-fold， thus enhancing calcium transport and absorption in the human intestine. The findings provide scientific evidence for the development of new calcium supplements and phosvitin phosphopeptides.

Abstract:In this study， the effect of quorum sensing signal molecule AI-2 on EPS production of L. fermentum TG4-1 and P. acidilactici 11-3 was investigated to explore the regulation mechanism of LuxS/AI-2 QS system on EPS secretion of lactic acid bacteria. EPS production and AI-2 activity of strains TG4-1-1 and 11-3 were measured by phenol-sulfuric acid method and V. harveyi BB170 bioluminescence method. The optimal concentration of exogenous AI-2 was selected and the growth， EPS production and AI-2 activity of the strain were measured. The morphology of the strain and polysaccharide after freeze-drying were observed by scanning electron microscopy. The results showed that both strains TG4-1-1 and 11-3 had the strongest AI-2 activity at 10 h， and the highest EPS yield at 22 h， reaching (195.863±1.643) mg/L and (125.179±1.458) mg/L， respectively. After screening， 100 μmol/L exogenous AI-2 was determined as the optimal supplemental concentration of strains TG4-1-1 and 11-3， which had no significant effect on the growth of the two strains at each stage (P>0.05). EPS production of strain TG4-1-1 at 16~22 h and strain 11-3 at 13~22 h were significantly promoted (P<0.05)； meanwhile， the activity of AI-2 was significantly increased at 10 h (P<0.05). After 100 μmol/L exogenous AI-2 was added for 13 h， the cells had smooth surface， regular shape and full shape. However， it had no obvious effect on the surface structure and morphology of exopolysaccharides. These results indicated that exogenous AI-2 at a certain concentration could promote the production of EPS in strains TG4-1-1 and 11-3， providing a certain reference for the mechanism of LuxS/AI-2 QS system regulating EPS.

Abstract:In order to clarify the changes of digestion and metabolism of main nutrients (protein and oil) in walnut and their antioxidant properties， this study took Juglans regia 'Xinxin 2' as the research object， and analyzed the metabolic processes of the two main components of protein and oil by using a simulated gastrointestinal digestive model. The metabolic changes at five different stages during digestion were determined by GC-MS and HPLC-MS/MS. The results showed that the total amount of free amino acids in protein digestion products increased from 3.50 μg/g to 61.85 μg/g with the passage of gastrointestinal digestion time (P<0.05)， For example， the content of arginine increased from 0.24 μg/g to 25.50 μg/g， and the content of lysine increased from 0.12 μg/g to 6.03 μg/g. The content of free fatty acids increased from 1.08 mg/g to 413.20 mg/g (P<0.05)， indicating that new fatty acids such as cis-11-eicosanoenoic acid and trans-10-19-enoenoic acid were produced under the action of enzymes during digestion. To explore the antioxidant properties of 5 different matching groups (the mass ratio of protein to oil was 1∶0， 7∶3， 1∶1， 3∶7， 0∶1) after digestion. The results showed that the antioxidant capacity increased with the increase of substance concentration. It was found that the antioxidant capacity was strongest when the protein-oil mass ratio was 1∶0， and when the concentration was 50 mg/mL， the DPPH and ABTS+ clearance rates were 80.65% and 81.02%， respectively. The absorbance value of Fe3+ reducing power was 1.55， indicating that the antioxidant capacity of walnut protein was better than that of oil， because the two digestive products of protein had antioxidant properties. This study provides data support for clarifying the digestion and metabolism mechanism of walnut principal components， and provides reference for the development of walnut products with high antioxidant function.

Abstract:To screen the lactic acid bactic with high PhIP adsorption capacity and to study adsorption characteristics by HPLC. The adsorption mechanism was discussed by scanning electron microscopy and Fourier transform infrared spectroscopy. The results showed that lactic acid bacteria 37X-6， 37X-15 and X3-1B had high adsorption capacity for PhIP， the adsorption rates were 80.43%， 83.36% and 76.69%， respectively. And the strains had the best adsorption effect when the cell concentration of strains was 1010 CFU/mL， pH was 6， temperature was 37 ℃ or adsorption time was 1.5 h. By heat treatment and enzyme treatment， it was found that the bacterial adsorption was a physical adsorption unrelated to its activity， and the bacterial adsorption rate increased after enzyme treatment. By scanning electron microscopy and Fourier infrared spectroscopy， it was found that PhIP cell surface was obviously damaged when strain adsorbed PhIP. The adsorption site of PhIP was mainly in the cell wall， and C-N， O-H， N-H， C-O groups were involved in the adsorption process. Lactic acid bacteria can adsorb PhIP， which was a physical adsorption， and its adsorption was related to the bacterial cell wall.

Abstract:The lactobacillus with high N-nitrosamine-degrading ability was screened from 16 strains of lactobacillus isolated from traditional fermentation products in Inner Mongolia by high performance liquid chromatography which was used to detect the content of N-nitrosamine in the co-culture system of lactic acid strain and N-nitrosamine， and its degradation characteristics and mechanism were revealed. The study showed that L.plantarum AL6-1 could efficiently degradate N-nitrosamines， and the degradation effect could be improved when the incubation time was 36 h， the initial pH was 4.5， the temperature was 37 ℃ or the inoculation concentration was 1010 CFU/mL in the culture system with the final concentration of N-nitrosamines of 1 μg/mL. The maximum degradation effect of N-dimethylnitrosamine and N-diethylnitrosamine was 63.90% and 61.65%， respectively. And the degradation rate of L.plantarum AL6-1 intracellular extract on NDMA and NDEA reached 70.28% and 71.88%， respectively， within 6 hours. It was determined that the removal of nitrosamines was mainly through the degradation of intracellular extract.

Abstract:To investigate the effect of lingonberry anthocyanins liposomes on the antioxidant function of Caco-2 cells under oxidative stress. Methods: A mixture of soy lecithin and cholesterol was used to prepare lingonberry anthocyanins liposomes by the thin film dispersion method and to evaluate their stability. A model of hydrogen peroxide-induced oxidative damage in Caco-2 cells was established to evaluate the protective effect of lingonberry anthocyanins liposomes on oxidatively damaged cells. Results: The lingonberry anthocyanin liposomes showed a smooth surface spherical structure with an average particle size of (213.2 ± 13.4)nm and a polydispersity index (PDI) of 0.201 ± 0.026. The particle size and pH of anthocyanins liposomes increased gradually after a period of time with the increase of storage time. At the concentration of 200 μg/mL， the survival rate of oxidatively damaged cells was 74.33% and 84.17% in the anthocyanins group and anthocyanins liposomes group， respectively； the content of ROS in oxidatively damaged cells decreased by 36.58% and 38.02%， respectively； the content of MDA decreased by 43.44% and 53.66%， respectively； the content of T-AOC increased by 3.42 and 8.89 times， respectively. SOD enzyme activity increased by 5.76%， 8.79%； CAT enzyme activity increased by 9.21%， 12.26%， respectively. Conclusion: Liposomes as carriers improve the biological activity of lingonberry anthocyanins， and lingonberry anthocyanins liposomes can reduce the levels of MDA and ROS in damaged cells， improve the survival rate of oxidatively damaged cells and enhance the activity of endogenous antioxidant enzymes and thus play an antioxidant role.

Abstract:We use hole method to study the antibacterial effect of the chitosan and its derivative on Helicobacter pylori， the results shows that it can not generate antibacterial circle in different concentration of chitosan and carboxymethyl chitosan. Chitosan oligosaccharide B(degree of deacet ylation，DD=94%， 50 mg/mL). has generated the antibacterial circle of Helicobacter pylori， the radius of bacteriostatic ring is (4.1±0.23) mm， while positive control (metronidazole， 10 mg/mL) is (5.5±0.15) mm. Chitosan oligosaccharide B (50 mg/mL) can vividly decrease the biological mass of Helicobacter pylori， while the chitosan oligosaccharide A (50 mg/mL) can not influence the growth of strain. Conclusion shows that chitosan oligosaccharide B(50 mg/mL) has the ability to restrain the Helicobacter pylori. The chitosan oligosaccharide A (deacetylation degree of 80%)， chitosan and carboxymethyl chitosan provided in this experiment did not have the effect of inhibiting Helicobacter pylori.

Abstract:The antibacterial activity and mechanism of COS against Aspergillus niger， Aspergillus ochraceus and Aspergillus variegatus were studied. The inhibitory activity of COS was revealed by minimum inhibitory concentration (MIC)， mycelial growth inhibition rate and spore germination inhibition rate. The test data showed that COS could significantly inhibit the growth of spoilage fungi， and its MIC for the tested fungi ranged from 15.6 to 31.2 mg/mL. After COS treatment， the cell membrane of spoilage fungi produced concave folds， the cell permeability increased， and a large number of cell components leaked， indicating that the cell membrane was damaged； COS also dose-dependently reduced the production of chitin， enhanced chitinase activity， and made a large amount of soluble protein extravasate. In general， COS can inhibit the activity of spoilage fungi， mainly through the effects of cell wall， cell membrane and cell metabolism. It can be widely used in food industry as an effective antifungal natural compound.

Abstract:In this study， the mutant MutLK10 was constructed by replacing the linker of β-xylosidase HJ14GH43 in order to reveal the mechanism of the linker on thermal adaptability of the β-xylosidase. MutLK10 was successfully expressed by Escherichia coli BL21 (DE3). Then， the enzymatic characteristics and 3D structure of MutLK10 were analyzed. The results showed that the optimum temperature of mutant MutLK10 was 20 ℃， which was 5 ℃ lower than that of the wild-type enzyme HJ14GH43. MutLK10 retained approximately 28% and 69% relative activities after being incubated at 20 ℃ and 10 ℃ for 60 min， respectively. Whereas HJ14GH43 retained approximately 70% and 88% relative activities after incubation at 20 ℃ and 10 ℃ for 60 min， respectively. Thus， MutLK10 had lower optimum temperature and worse thermalstability than HJ14GH43. The linkers of HJ14GH43 and MutLK10 were constructed as coil regions on the surfaces of proteins. Structural analysis showed that the negative potentials of the coil regions increased after the mutation， which led to the increase of hydrophilicity. It indicates that increasing the proportion of acidic amino acids in the linker can help the β-xylosidase compete for hydration by increasing the surface negative electrostatic potentials， that may result in the increase of the interactions between the enzyme and solvents and finally enables the enzyme to adapt to low-temperature environments. This study provides a reference for thermal adaptability modification of β-xylosidases and other industrial enzymes.

Abstract:The effects of dietary fiber (DF) and ferulic acid (FA) on the aggregation of Glutenin macropolymer (GMP) were studied by measuring the protein particle size distribution， molecular weight distribution and subunit changes during dough resting； At the same time， the interactions between dietary fiber or/and ferulic acid and GMP protein molecules were explored by fluorescence spectrum， ultraviolet spectrum and free amino content. The results showed that during the dough resting process， GMP aggregated from small particle size (<11 μm) into large particle sizes (>50 μm). FA depolymerized the glutenin subunits in the high molecular weight range. DF+FA reduced the impact of this depolymerization on the GMP molecular weight distribution and maintain the subunit ratio at 0.25. Fluorescence spectra and ultraviolet spectra showed that FA exposed the protein structure segments containing tryptophan and tyrosine residues to a more polar aqueous environment. The content of free amino groups in protein molecules might be significantly reduced (P<0.05) by 22.48% and 17.38% respectively (when the dough resting for 90 min) through covalent cross-linking between DF/FA and GMP， resulting in changes in protein structure. Conclusion: The addition of DF and FA had an impact on the molecular aggregation of GMP proteins， and generated intermolecular interactions with GMP proteins， resulting in changes in the structure of GMP.

Abstract:In order to explore the interaction between cross-linked sugar beet pectin (CSBP) and waxy corn starch (WCS)， different amounts of CSBP were added to WCS to prepare WCS-CSBP blends， and their gelatinization， rheological and retrogradation properties were investigated. The results showed that with the addition of CSBP， the breakdown， setback value， peak value and final viscosities of the blends gradually increased (P<0.05)， while the gelatinization temperatures showed no significant difference (P>0.05). After addition of CSBP， both the consistency coefficient (K) value and hysteresis area of the blends increased (P<0.05)， the shear stability decreased， and the storage modulus (G') and loss modulus (G") increased. Particle size analysis suggested that addition of CSBP could promote the swelling of WCS particles， and the D50 of the blends increased remarkably from 46.19 to 175.95 μm (P<0.05). As the CSBP concentration increased， the pore size of the blend gel surface became larger， the pore structure density became lower， and the pore wall thickness became higher. In addition， the incorporation of CSBP significantly decreased the gel strength(P<0.05) and the recrystallization of starch molecules during the storage of the blends， indicating a good anti-retrogradation property. The addition of CSBP can significantly improve the physicochemical properties of WCS， and the results of this study can provide an important reference for the application of CSBP in starch-based foods.

Abstract:In this study， rice starch was used as raw material to prepare octenyl succinic anhydride(OSA) modified starch. The sunflower seed oil was used as oil phase， OSA hydrophobically modified starch and 5 kinds of anionic emulsifiers were used to build oil-in-water Pickering emulsions. The physical stability of the emulsion was studied by determining the emulsion volumes， droplet size distributions and microstructure. The results showed that when the emulsifier concentration was 1.0 wt. %， the emulsion stabilized by hydrophobic starch/anionic emulsifier had better physical stability than the emulsion stabilized only by starch particles. When the ratio of starch and xanthan gum was 3︰1， the emulsion had the best stability and the smallest droplet size， which was 83.01 μm. When the ratio of starch and sodium carboxymethyl cellulose was 4︰1， the emulsion had the best stability and the smallest droplet size， which was 76.29 μm. The laser confocal scanning microscope result showed that when the hydrophobic starch particles were used in combination with anionic emulsifiers， the starch particles were adsorbed on the oil-water interface and present a mechanical barrier， which increased the stability of the emulsion.

Abstract:Objective: Shandong pancake is one of the traditional staple foods in northern China. This study aimed to investigate the alleviating effects of Shandong pancake with sourdough fermented by Lactobacillus plantarum on type 2 diabetic mice induced by high-fat diet and streptozotocin. Methods: After building the type 2 diabetic mice model successfully， test in groups with normal control (NC)， model control (MC)， positive control (PC)， non-fermented pancake (NFP) and fermented pancake (FP). The intervention was continued for 6 weeks， during which the fasting body weight and fasting blood glucose of the mice were measured weekly. At the end of the experiment， the mice were tested for fasting serum insulin， blood lipids， pancreatic tissue pathology， short-chain fatty acids， and gut microbiota. Results: Compared with mice in the MC group and NFP group， FP can reduce fasting blood glucose levels and insulin resistance in diabetic mice， improve dyslipidemia， and relieve pancreatic damage. Moreover， the intake of FP promoted the production of short-chain fatty acids and regulated the gut microbiota， which may be related to the fermentation products formed during the fermentation of sourdough. Conclusion: Shandong pancake with sourdough fermented by Lactobacillus plantarum can be used as a functional staple food for combating type 2 diabetes.

Abstract:Objective: To investigate the improvement of glycolipid metabolism in mice with type 2 diabetes mellitus (T2DM) induced by polyphenol extract from mung bean sprout. Methods: C57BL/6 mice were randomly divided into normal control group， model group， high， medium and low dose groups of germinated mung bean polyphenol extract and positive control group. A mouse model of type 2 diabetes was established by high fat diet combined with intraperitoneal injection of Streptozotocin (STZ). After continuous gavage for 5 weeks， fasting blood glucose， glucose tolerance， organ index， blood lipid level and liver morphology were measured. Results: during the experiment， compared with the model group， the polyphenol extract of germinated mung bean could reduce the fasting blood glucose and significantly improve the glucose tolerance of mice (P＜0.01)； Improve the concentration of serum lipid indexes (TC， TG， LDL-C， HDL-C) in T2DM mice(P＜0.01)； The activity of ALT and AST in serum of mice was reduced， and the morphology of liver tissue in STZ induced diabetic mice was repaired. Conclusion: a certain dose of germinated mung bean polyphenols extract can effectively improve the symptoms of hyperglycemia and dyslipidemia in type 2 diabetic mice.

Abstract:In order to explore the effects of milk fat aggregation caused by thermal processing on the digestion and absorption characteristics of milk fat and lipid metabolism， the changes of fat particle size， potential and lipolysis rate during the digestion of aggregated milk fat and non aggregated milk fat were measured by vitro simulated digestion； The contents of fat in feces， triglycerides and cholesterol in serum and liver at different times were measured by animal experiments. The average particle size of aggregated milk fat group in the stomach (7.40 μm) was significantly increased (P<0.05) compared to the initial stage(4.54 μm). The average particle size of non aggregated milk fat group in the stomach (9.26 μm) was also significantly increased (P<0.05) than the initial stage (2.80 μm)； The amplitude of potential change in the aggregated milk fat group was smaller than that in the non aggregated milk fat group. The release rate and degree of fatty acids in the aggregated milk fat group are lower than those in the non aggregated milk fat group， indicating that the digestion speed of aggregated milk fat is slower than that of non aggregated milk fat. The results of in vivo experiments in rats showed that the fat excretion rate of the aggregated milk fat group (8.68%) was higher than that of the non aggregated milk fat group (6.66%)， indicating a low bioavailability of aggregated milk fat. After 6 hours of gavage， the serum triglycerides (0.57 mmol/L) in the aggregated milk fat group were significantly higher (P<0.05) than those in the non aggregated milk fat group (0.45 mmol/L)， and the cholesterol (1.76 mmol/L) in the aggregated milk fat group was also significantly higher (P<0.05) than those in the non aggregated milk fat group (1.46 mmol/L)； The liver triglycerides (0.0090 mmol/L) in the aggregated milk fat group were significantly lower (P<0.05) than those in the non aggregated milk fat group (0.0117 mmol/L)， and the cholesterol (0.0058 mmol/L) in the aggregated milk fat group was also significantly lower (P<0.05) than those in the non aggregated milk fat group (0.0069 mmol/L)， indicating that the aggregation of milk fat also affects lipid metabolism. Therefore， through the vitro model digestion system and rats gavage experiment， we found that the aggregation of milk fat will affect its digestion and absorption and lipid metabolism in rats.

Abstract:Objective: To explore the molecular mechanism of camel milk to relieve acute alcoholic liver injury in mice. Methods: ICR mice were randomly divided into normal group (NC)， model group (ET)， camel milk group (CM) and camel milk intervention group (ET+CM)， and measured liver tissue (AST and ALT) and serum indexes (TNF-α， IL-10， 1L-6 and IL-1β) to reflect the protective effect of camel milk on the liver； and based on transcriptomics research methods to explore the mechanism of camel milk to protect the liver. Results: Compared with the ET group， camel milk intervention reduced the alcohol-induced AST， ALT， TNF-α， 1L-6 and IL-1β levels， and at the same time increased IL-10 levels. Furthermore， transcriptome sequencing was performed on four groups of mouse liver tissues. The results showed that a total of 1426 differentially expressed genes were detected in the ET group and the ET+CM group (673 were up-regulated genes and 753 were down-regulated genes)， and then combined with gene function and enrichment analysis， it was found that the differentially expressed genes were mainly significantly enriched In the three inflammatory pathways of MAPK， Toll-like and NF-κB signaling. Six representative differential genes， including CD14， TLR5 and TLR9， were determined by real-time fluorescence quantitative PCR. The results showed that compared with the model group， the expression levels of CD14， IL-1β， IL-6， TLR5 and TLR9 were significantly decreased after camel milk intervention， and the expression levels of IL-10 were significantly increased， which was consistent with the transcriptomic sequencing results， and verified the accuracy of sequencing data. The results laid a good foundation for the analysis of the molecular mechanism of camel milk on alcoholic liver injury.

Abstract:To evaluate the degradation mechanism of anthocyanins and carotenoids from compound fruit and vegetable juice rich in anthocyanins and carotenoids， cyanidin-3-O-glucoside (C3G) and β-carotene was used as the research object. By constructing different simulated systems， the effects of metal ions， pH， sugar species and content on the C3G and β-carotene stability were studied. The results indicated that the thermal degradation of C3G and β-carotene fitted to the first-order reaction models， and the degradation of both components were nonspontaneous endothermic reactions. After C3G and β-carotene were compounded， the stability of anthocyanin did not change significantly while that of β-carotene decreased. In addition， the effects of different sugar types and contents on the thermal degradation of C3G and β-carotene in the simulated compound system were different. The stimulative effects of sugars on degradation of C3G were according to the ascending order: fructose > sucrose > glucose， and the stability of anthocyanins increased gradually with increment of sugar contents. However， the effects of these sugars on β-carotene were not significant， and the stability of β-carotene decreased gradually with increment of sugar contents. The results provided the theoretical basis for the research and development of compound fruit and vegetable juice rich in anthocyanins and carotenoids.

Abstract:Xianggan tea is a new type of Ganpu tea made from Hunan Yueyang Jinpen pomelo and Pu'er tea， there is a saying that‘the longer the storage time， the better the quality’. However， the naturally aged Xianggan tea has a long cycle and unstable quality. This study designed the optimal ultrasonic accelerated aging conditions through orthogonal experiments， and combined with principal component analysis to study the changes in the main chemical components， volatile components and sensory evaluation of Xianggan tea treated with optimal ultrasonic conditions. The results showed that: 1) The optimal conditions for ultrasonic aging of Xianggan tea were ultrasonic power 70 W， ultrasonic time 55 min， and ultrasonic temperature 30 ℃； 2) After ultrasonic treatment， the total flavonoids and hesperidin in Xianggan tea showed an increasing trend， with a total flavonoid content increase of 22.63% and hesperidin increase of 11.11%， while the total polyphenols increase was not significant； There are 53 kinds of volatile components in the untreated and ultrasonicated Xianggan tea， with the highest content being D-limonene， trans-β-Farnesene and γ-Terpinene. During the ultrasonic aging process， 14 kinds of aroma components disappear and 14 kinds of substances are formed. The main aged flavors of α-terpineol， 3-methyl-4-isopropylphenol， (Z)-β-ocimene， etc. increase， while the content of methyl o-methylaminobenzoate and D-limonene decrease. The aroma， soup color， taste， and acceptance of Xianggan tea treated with ultrasound are better than those without treatment； 3) The results of principal component analysis show that six principal components are extracted， and the contribution rate of the first principal component is 73.17%. The eigenvalues of the first three principal components are all greater than 1， and the cumulative variance contributes the rate reached 95.85%， the main components that affect the quality of Xianggan tea after ultrasonic treatment are the same as those related to aging， indicating that ultrasonic treatment can accelerate the aging of Xianggan tea and can further improve the quality of Xiang citrus tea.

Abstract:Taking the lipase activity in the fermentation broth as the target， through single factor， Plackett-Burman， steepest climbing and response surface tests， the optimal conditions for the production of lipase by the Moesziomyces aphidis were optimized. The results showed that culture conditions such as glucose， NaNO3， yeast extract powder， MgSO4， peanut oil， and Tween-80 medium components， the amount of liquid filling， and the fermentation temperature all affected the lipase activity. Among them， the 3 most significant factors affecting the lipase activity are the addition amount of NaNO3， the addition amount of yeast extract and the culture temperature. The optimal conditions after optimization are: the addition amount of NaNO3 is 3.1 g/L， the addition amount of yeast extract is 2.24 g/L， and culture temperature is 25.8 ℃. On this condition， the lipase activity in the fermentation broth is 83.14 U/mL， which is close to the predicted value of the regression equation obtained by the response surface， and is 2.6 times higher than the enzyme activity in the initial medium， indicating that the regression model can better optimize the lipase fermentation conditions. This study explored the industrial application potential of the Moesziomyces aphidis， providing a reference for broadening the source of lipase.

Abstract:Salted egg white is a by-product of egg yolk processing. In order to improve its utilization rate， a simple， feasible and low-cost process for continuous separation of several important proteins in salted egg white was established in this study. Ovomucin， ovalbumin and ovomucoid were isolated from salted egg white by isoelectric point precipitation， (NH4)2SO4， salting out and alcohol precipitation. The results showed that the yields of ovomucin， ovalbumin and ovomucoid were 83%， 98% and 76%， respectively， at laboratory scale. SDS-PAGE gel electrophoresis showed that the purities of the three proteins were 89%， 92% and 98%， respectively. In addition， the ovalbumin separated by alcohol precipitation still had good foaming property after redissolution， indicating that the separation method could maintain the functional properties of the protein well.

Abstract:Aim: To provide theoretical support for the utilization of betacyanins derived from red pitaya fruit in food processing. Methods: Firstly， investigation of the impact of extraction solution， solid-liquid ratio， pH of extraction solution， temperature and time on the yield of betacyanins extracted from the red pitaya peel， to optimize the extraction conditions. Secondly， the betacyanins extraction were subjected to UPLC-MS analysis for the determination of their content and structural characteristics. Finally， the impact of metal ions， including Cu2+ and Fe2+， on its stability was evaluated. Results: An optimal extraction condition of betacyanins from red pitaya peel involves using distilled water as the extractant， maintaining a solid-liquid ratio of 1∶5， adjusting pH to 5， and conducting at 30 ℃ for 60 min. The extract contained 6 monomers of betacyanins， with a concentration of 95.2 mg/g. The main monomers were phyllocactin and betanin， accounting for 46.5% and 34.4%， respectively. The addition of CuSO4 and FeCl2 has disturbed the stability of betacyanins， with CuSO4 having a greater impact than FeCl2. Specifically， CuSO4 caused a reduction in absorbance values and color changes even at concentration as low as 0.05 mg/mL， while FeCl2 accelerated the trend towards color change when added at concentration exceeding 0.10 mg/mL. Conclusions: The red pitaya peel waste presents a promising source of betacyanins， with a simple and feasible extraction process. However， the presence of metal ions such as Cu2+ and Fe2+ can negatively affect their stability， thus avoiding contact with copper and iron utensils during processing and storage is recommended.

Abstract:Fresh Channa argus was used as raw material to make fish soup under normal pressure and high pressure respectively. By measuring the nutritional components， color， taste substances and other indicators， combined with sensory evaluation， the effects of different thermal processing methods on the nutritional components and edible quality of fish soup were explored. The results show that compared with the traditional thermal processing method， the soluble solids content and crude protein content of high-pressure treated fish soup reach more than 4%. The content of mineral elements Na and K reached more than 8 000 mg/L， and the content of Ca and Mg reached more than 1 000 mg/L； The total amount of hydrolyzed amino acids reaches more than 300 mg/L. Among them， the contents of essential amino acids and hydrolyzed amino acids were about 6 times and 3 times higher than those of normal pressure treatment respectively. Under high pressure treatment， the total amount of free amino acids and the content of umami amino acids in fish soup increased by more than one time， which was consistent with the result of electronic tongue umami detection. Although the fish soup treated by atmospheric pressure has better aroma and higher acceptability， its taste and nutritional components are inferior to those of fish soup treated by high pressure. To sum up， the high-pressure treated fish soup can better maintain the nutritional performance of Channa argus. The fish soup is more fragrant and more popular with consumers. Its application in the preparation of fish soup can help to realize the full utilization of Channa argus resources， improve the resource utilization rate and economic benefits.

Abstract:Objective: To prepare oligoprocyanidins from Seabuckthorn seed meal by ultra-high pressure pretreatment and ultrasonic extraction， and analyze its structure and antioxidant properties. Box-Behnken adopted to optimize the preparation process of oligoprocyanidins from seabuckthorn seed meal. Infrared Spectroscopy(IR) and Ultra performance liquid chromatography-mass (UPLC-ES-MS) spectrometry were used to analyzed the structure and the antioxidant activity was determined by DPPH， ABTS and FRAP. Result: The optimal process parameters were 1∶15 (g/mL) material-to-liquid ratio， ultrasonic time 28 min， ultrasonic temperature 45 ℃， solvent pH 2.85， the sea buckthorn seed meal proanthocyanidin yield was 6.556%， and the average degree of polymerization was 3.35， which mainly composed of dimer， trimer proanthocyanidins and some flavonoids. The dimers include three B-type dimers and one A-type dimer. The Sea buckthorn meal oligoprocyanidins showed good antioxidant activity， with DPPH， ABTS and FRAP values of 2.205， 1.307 and 0.8143 mmol Trolox/g DW， respectively. Conclusion: oligoprocyanidins from Seabuckthorn seed meal have strong antioxidant activity， and are structurally distinct from proanthocyanidins from grape seed meal.

Abstract:The drying preparation technology of probiotic microcapsules is the key to ensure the stability of probiotics during long-term storage. In order to objectively evaluate the drying effect of different drying techniques on probiotic microcapsules. In this paper， the applications of spray drying (B1)， vacuum freeze drying (B2)， fluidized bed drying (B3) and microwave vacuum freeze drying (B4) 4 in probiotic microcapsule drying were analyzed. The multi-process grading evaluation index system of probiotic microcapsule drying technology was constructed. Based on the queuing theory， the sequence grades and weights of water characteristics， apparent characteristics， structural characteristics， chemical characteristics， biological characteristics and evaluation factors were determined. At the same time， the cloud evaluation model of probiotic microcapsule drying technology was constructed by introducing the golden section method and cloud generator principle， and the drying effects of four drying methods on probiotic microcapsules were quantitatively evaluated. The results showed that the comprehensive evaluation of the four drying techniques were ZB1 (0.4624， 0.0674， 0.0088)， ZB2 (0.5810， 0.0591， 0.0106)， ZB3 (0.6772， 0.0595， 0.0111) and ZB4 (0.7635， 0.0582， 0.0119)， respectively. The comprehensive order of drying performance of probiotic microcapsules is B4 > B3 > B2 > B1. The research method and conclusion can provide theoretical support and useful reference for enriching and perfecting the drying technology of probiotic microcapsules.

Abstract:In order to expand the quick-frozen method of food， the method of quick freezing fresh jujube slices by liquid air spray was proposed. The model of liquid air spray quick freezing tank was established by COMSOL Multiphysics. The velocity field and temperature field of fresh jujube slices were simulated， and the temperature changes of fresh jujube slices at different times were obtained by field probes and boundary probes during the quick freezing process. By comparing the quick freezing effects of different liquid air injection speeds (0.02， 0.04， 0.06， 0.08， 0.1 and 0.2 m/s)， it is concluded that the time of fresh jujube slices to meet the quick freezing requirements decreases with the increase of flow rate. When the flow rate is 0.06 m/s， the freezing rate is faster and the cold energy is used more fully. The quick freezing tank models with five outlet positions (lower right， upper right， directly above， upper left and lower left) were established. The results show that the model with the outlet in the upper left can realize the quick freezing of fresh jujube slices more efficiently and the temperature distribution of fresh jujube slices is more uniform. Compared with the existing cryogenic liquid nitrogen tunnel quick freezing， the liquid air spray quick freezing has a shorter time to meet the requirements of quick freezing， and has outstanding advantages in heat transfer and energy saving.

Abstract:Polysaccharides are often used as food degradable packaging materials. Chitosan and cellulose nanofibers as edible film substrates have good waterproof performance， but lack of mechanical properties and physical and chemical properties. In this experiment， different concentrations(0%， 0.5%， 1%， 1.5%， 2%) of soybean protein isolate (SPI) were mixed with chitosan and cellulose nanofibers to prepare edible membranes. Fourier transform infrared spectroscopy (FTIR)， X-ray diffraction (XRD)， differential scanning calorimetry (DSC)， scanning electron microscopy (SEM) and other methods were used to study the microstructure， electrostatic action and the influence on the properties of edible films. The results show that the interaction between SPI and chitosan and cellulose nanofibers is mainly hydrogen bond and electrostatic， and the interaction is the strongest when the SPI content is 1%. The network structure is dense and the cross section becomes smoother. When SPI content is 1%， the tensile strength and elongation at break of edible membrane are significantly increased to 6.42 MPa and 97.47%， the opacity and contact angle are significantly increased， the water vapor transmittance and oxygen transmittance are decreased to 0.86 g·mm·m-2·h-1·kPa-1 and 10.63 g·m-2·d-1， respectively. Water absorption and solubility are obviously weakened. The above analysis shows that adding 1% SPI can optimize the performance of the edible membrane. This experiment provides theoretical reference for the preparation and application of the proteoglycan edible membrane.

Abstract:PS-11S composite edible film was prepared with potato starch (PS) and soybean globulin (11S) in different proportions (m/m). X-RD， FTIR spectrum， texture， optical properties， permeability， scanning electron microscopy were used to study the interforce， microstructure and mechanical properties of edible film components. The results showed that 11S and PS cross-linked with each other through hydrophobic interaction and hydrogen bond to form a mesh structure and promote the formation of edible film by X-RD and FTIR spectrum analysis. With the increase of 11S content， the mechanical properties of edible film increased first and then decreased. When the ratio of 11S and PS was 2∶15， the elongation at break of edible film reached the maximum 46.69%， the transmittance of water vapor reached the minimum 5.63 mm/m2d·kPa， and the transmittance of oxygen and carbon dioxide were 8.48 g/d·m2 and 12.47 g/d·m2， respectively. When the content of 11S is too high， the porosity of the edible membrane system increases and even cracks occur. Therefore， when the ratio of 11S to PS is 2∶15， the edible film has moderate hardness， compact spatial structure and excellent mechanical properties， which provides a research basis for the preparation of protein-starch composite edible film.

Abstract:The research on the influence of phase temperature storage technology on the microbial population structure on the surface of daylily provides a reference for the preservation of daylily. The daylily collected from Qingyang， Gansu was packaged in groups and stored in the refrigerator (4 ℃±1 ℃)， cold storage (0 ℃±0.5 ℃) and phase temperature environment (-0.5 ℃±0.1 ℃). The browning was measured at 7 days， and extracting surface microbial samples， using specific primers to perform PCR amplification on the V3-V4 region of the bacterial metagenomic 16S rRNA and the fungal metagenomic ITS1-1F region， analyzing the microbial relative abundance and diversity of daylily based on Illumina high-throughput sequencing technology. At the genus level， Dothideomycetes， Microbotryomycetes， Tremellomycetes， Eurotiomycetes， and Sordariomycetes are the dominant flora of daylily fungal communities， and Cyanobacteriia， Gammaproteobacteria， Alphaproteobacteria， Bacilli and Clostridia are the dominant flora of the daylily bacterial community. From the perspective of the number of OTUs in the dilution curve， the diversity of fungi and bacteria on the surface of daylily stored at phase temperature is the lowest， which proves that storage at phase temperature can effectively inhibit the diverse growth of surface microorganisms.

Abstract:The unclear composition of bitter substances in peony seeds limits the comprehensive development and efficient utilization of peony seeds. In this study， a combination of organic solvent extraction and sensory evaluation was used to separate and identify the bitter substances in peony seeds by ultra-high performance liquid chromatography-quadrupole/orbitrap high-resolution mass spectrometry (UPLC-HRMS). The results of the study showed that the peony seed sample was extracted by n-hexane， citric acid aqueous solution， n-butanol， and purified by AB-8 macroporous resin. 5 components were obtained: F-Ⅱ-1-MR1， F-Ⅱ-1-MR2， F-Ⅱ-1-MR3， F-Ⅱ-1-MR4， F-Ⅱ-1-MR5. Two bitter components were screened by sensory evaluation: F-Ⅱ-1-MR2， F-Ⅱ-1-MR3. UPLC-HRMS was used to analyze and identify those bitter components. A total of 24 compounds were identified， including 7 monoterpene glycosides， such as paeoniflorin， 7 flavonoids， such as luteolin， 2 stilbene， such as resveratrol， 6 fatty acids， such as 9，12，13-trihydroxy-10，15-octadecadienoic acid， and 1 kind of organic acids was benzoic acid. Among them， paeoniflorin is the highest yield component in peony seed extract， and it is also the main bitter compound in peony seeds.

Abstract:Purine compounds are important natural toxins in soybean， and excessive intake can induce hyperuricemia and gout. In order to reveal the levels of purine compounds in different soybeans， an ultrahigh-performance liquid chromatography (UPLC) method was developed for the determination of four purine compounds in soybeans， and the levels of guanine， adenine， xanthine， and hypoxanthine in 58 main planted soybeans in China were determined. The results showed that the method had good linearity (R2>0.9995) in the linear range (0.2~10 mg/L) and the detection limits were 0.0412~0.1001 mg/L. The precision RSD was less than 0.6000% and the RSD values for adenine， guanine， xanthine and hypoxanthine were 1.1103%， 1.0728%， 1.3762， and 0.9457% in that order. The recoveries of the four purine compounds spiked ranged from 92.5902% to -100.1373%. This paper also examines the comparative determination of the ideal extraction solvent (equal volume solution of trifluoroacetic acid and formic acid) and hydrolysis time (30 min). The data on the content of purine compounds in some of the main soybean varieties in China determined by applying this method showed that the purine content in different soybean varieties: high protein varieties > conventional varieties > high oil， protein， and lipid double-high varieties and the purine content in non-fishy soybean varieties differed significantly (2 013.06~2 824.54 mg/kg)， and the findings of this study can provide scientific guidance for soybean processing and consumption.

Abstract:To provide an applicable method for comprehensive evaluation of fruit nutrient quality， 14 key nutritional indicators were selected by comparing and analyzing Chinese intake of dietary nutrients and the satisfaction degree of their needs. Among which vitamin A， vitamin B1， vitamin B2， vitamin C， vitamin E， calcium and selenium were significantly inadequate nutrients， protein， niacin， potassium， magnesium and zinc were inadequate nutrients， and fat and sodium were excessive nutrients. Combined with the corresponding nutrient content levels of various fruits， the fiducial values of key nutrients content were calculated. The nutrient quality index of key nutrients for fruit products was obtained by comparing the contents of key nutrients with the corresponding fiducial values. According to the deficiency and excessiveness degree of Chinese dietary intake of various key nutrients， the weight of the nutrients was determined and composite nutrient quality index for fruit (CNQIF) model was established. According to the distribution of CNQIF for representative fruits， the grading standards were established. The comprehensive evaluation results of nutritional quality of 48 representative fruits by using CNQIF model showed that 1 fruit of 5A grade， 2 fruits of 4A grade， 1 fruit of 3A grade， 5 fruits of 2A grade， 9 fruits of A grade， 12 fruits of B grade and 18 fruits of C grade. CNQIF and grading standards can reflect the nutritional quality of fruits comprehensively， and can be used for nutritional quality comprehensive evaluation and comparison of fruits (such as different species， varieties and sources)， setting nutrient quality standards of fruit products and guiding consumption (especially suitable for Chinese consumers)， etc.

Abstract:Sugar， organic acid and free amino acid are vital indicators not only for fresh fruit， but also for fruit processing. The profile of sugar and organic components， and free amino acids for five traditionally fine and new litchi (Litchi chinensis Sonn.) cultivars including Guiwei， Feizixiao， Nuomici， Xianjinfeng and Jingganghongnuo were investigated， and then the characteristics of fruit quality and flavor were compared among cultivars， with the target to promote fruit quality evaluation， fruit processing and industry optimization in litchi. Twenty two litchi orchards in the main production areas of Guangdong， Guangxi and Fujian were selected， where total 52 matured fruit samples from 5 litchi cultivars were collected. All flesh of matured fruit samples that peeled off peels and seeds， soaked in liquid nitrogen， ground into pulp by a mill and store for later determination. High performance liquid phase (HPLC) method was used to determine sugar and organic acid components. Ninhydrin post column derivatization method was adopted to analyze amino acid profile by automatic amino acid analyzer (8800 Hitachi). Further， the quality and flavor of the five cultivars were compared. The results showed that glucose， fructose and sucrose were determined as the sugar components of litchi. Among them， 'Guiwei'， 'Xianjinfeng' and 'Jingganghongnuo' belonged to sugar component balanced cultivars， however， 'Feizixiao' and 'Nuomici' were identified as reducing sugar accumulation type and sucrose accumulation type， respectively. Besides， by comparing the sugar content of different cultivars， the three sugar components of each cultivar could be perceived by humans. Three sugar components of all varieties can be perceived. Nine kinds of organic acids were observed in all litchi cultivars. Malic acid was the main organic acid component， followed by tartaric acid or acetic acid， and maleic acid was the minimum. However， only a small amount of samples in all litchi cultivars could detect low content of maleic acid， and most of them were not detected. Litchi fruits contained 30 free amino acids， and gamma-aminobutyric acid (GABA) or alanine(Ala) was the maximum ingredients. There were significant differences for the contents of sugar and organic acid components， free amino acids (with the exception of asparagine (Asn)， glutamate (Glu) and cysteine (Cys)) and taste amino acids (with the exception of umami amino acids) among cultivars (P<0.05). The contents of total organic acid and most organic acid components， total free amino acids， sweet and bitter amino acids in 'Feizixiao' are significantly higher than those in all the other four cultivars. Fructose was the greatest contributor to sweetness of litchi fruit， irrespective of cultivars， with significant higher contribution values than those of the other two sugar components (P<0.01). The contribution of sweet amino acids to sweetness of litchi fruit was much lower than that of the three sugar components， but Ala contributed most to the sweetness among free amino acids. The most contributors of umami and bitter tastes were Glu and valine(Val)， and tartaric acid was the greatest source of sourness taste. What's more， GABA contributes greatly to astringency. Since significant differences in sweetness values， sweet/sour ratios， sugar/acid ratios， umami/sweet amino acid ratios and sweet/bitter amino acid ratios were observed among cultivars (P<0.05)， the quality and flavor of the five cultivars considerably differed by these indexes. In conclusion， the contents of various flavor substances in litchi fruits of the five cultivars are significantly different. Fructose， Ala， Glu， Val， GABA and tartaric acid are the key ingredients for the unique flavor of litchi fruits. Great variation is found in the quality and flavor of litchi cultivar as assessed by different evaluation indexes. It shows that it is still necessary to investigate the typical evaluation indicators for litchi in the future.

Abstract:Geraniol is a monoterpene with a rose trait. This study aims to know the accumulation patterns of geraniol and its glycoside， and the other is to know the contribution of geraniol to the aroma of black tea. The result showed that the CSS (C.sinensis var. sinensis) cultivars possess a higher content of geranyl primeveroside than that in the CSA (C.sinensis var. assamica) cultivars. The amount of geranyl primeveroside in tea young leaf was highest among all tissues of the tea plant， while tea roots had the lowest accumulation of geranyl primeveroside. The fresh leaves of the tea plant in March had a higher accumulation of geraniol compared to those in other months. Furthermore， the results showed that the odor activity value of geraniol in six black tea infusions ranged from 3.93 to 28.38， strongly supporting the potential contribution of geraniol to the aroma of black tea samples. The strong coregulation was obtained between the expression of seven terpene synthase candidate genes and the accumulation of geranyl primeveroside. This work gives insight into the accumulation patterns of geraniol and its primeveroside and promote the research about the biosynthesis and regulation mechanism of geraniol in tea plant.

Abstract:Aroma is one of the most important factors to evaluate the quality of tea. In order to systematically analyze the difference of aroma components in new and aged Dahongpao oolong teas， and thus provided a scientific basis for storing Dahongpao teas， headspace-solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS) and gas chromatography-olfactometry(GC-O) were mainly used in this study. A total of 185 aroma compounds were identified from new Dahongpao and aged Dahongpao oolong teas by HS-SPME-GC-MS， and 45 aroma-active components were identified by using GC-O method. Partial least squares discriminant analysis (PLS-DA) and nonparametric test indicated that there were 31 key aroma compounds with statistical differences between the two groups (P<0.05). Whereafter， the key aroma compounds with statistical differences and aroma-active components in new and aged Dahongpao were further investigated by combining the peak areas and aroma intensity (AI). Results showed that the peak areas of 2-acetylfuran， 3，5-dimethyl-2-ethylpyrazine， linalool， phenylethyl alcohol， phenethyl acetate， indole and hexyl hexanoate had the same trend as those of aroma intensity. Therefore， these key differential aroma-active components have important contribution for distinguishing the aroma between the new and aged Dahongpao oolong teas， which present a potential applications in the identification of aged Wuyi rock teas. The results of this study provide some technical references for the scientific evaluation of Dahongpao aroma and the discrimination of "new and aged" teas.

Abstract:A method for the simultaneous determination of multiple phenolic compounds in aquatic products was investigated because there is a lack of standards for the detection of multiple phenolic compounds in aquatic products at home and abroad， and the existing detection methods cannot detect multiple phenolic compounds at the same time. A modified QuEChERS pretreatment method was used to optimize the mass spectrometry conditions， extractant and extractant dosage， and the response surface Box-Behnken method was used to optimize the clean-up agent. The results showed that the detection limits of the method for the determination of 18 phenolic compounds were in the range of 0.001-0.012 mg/kg， the spiked recoveries were 83.1%-107.7% and the relative standard deviations were 1.9%-9.5%. The method was applied to the actual samples and the results showed that phenolic compounds were detected in all molluscs， with scallops and razor clams showing the most serious phenolic contamination， followed by oysters， mussels and sea cucumbers， and squid the least contaminated. The method was developed to provide a technical reference for the development of national standards for the detection of phenolic compounds and the safety regulation of aquatic products.

Abstract:To establish a multiple identification method of animal species in meat by using a universal molecular beacon with probe melting curve analysis. Through multi sequence alignment of the genomes of 9 common edible livestock and poultry， the gene fragments with specific structure in the 16S rDNA of the mitochondrial genome were selected as the detection target sequence. A pair of primers and a long-chain molecular beacon for universal detection were designed by the method of bioinformatics analysis. The characteristic annealing temperature (Tm) of different animal derived components was determined based on real-time polymerase chain reaction (RT-PCR) and melting curve analysis， while the sensitivity and specificity of the identification method were investigated. The RT-PCR based on universal primers and molecular beacon was performed on genome samples derived from 9 animal species. The amplified product of each sample was single， and the sequencing result was consistent with its reference sequence. While a dilution range of 108 to 101 copies/μL of standard DNA of pork was used as template， the RT-PCR was performed validly with incremental Ct value from 15 to 36 cycles， and the characteristic Tm was about (68.0±0.1) ℃ steadily by melting curve analysis. The detection result also showed that identifiable specific annealing temperature was obtained for each sample derived from the livestock and poultry meat investigated with Tm of 68.0 ℃ for pigs， 64.3 ℃ for cattles， 65.1 ℃ for sheep， 65.8 ℃ for donkeys， 63.4 ℃ for horses， 60.6 ℃ for camels， 61.8 ℃ for dogs， 52.6 ℃ for chickens and 56.7 ℃ for ducks. While the mixed genome derived from different animal species was detected， the results could show the independent melting peaks of various species genes or the emergence of a new fusion peak. The RT- PCR detection method based on universal primers and molecular beacon can realize the single-tube multiple identification of common livestock and poultry meat food species with ideal sensitivity and specificity. With high application value， this method could be used in meat adulteration screening.

Abstract:As a functional food， dietary fiber plays a variety of physiological functions in the human body and is of great significance to maintain human health. Functional gastrointestinal diseases (FGIDs) are a group of functional gastrointestinal diseases that are chronic or recurrent without organic changes. It not only seriously affects the life quality of patients， but also increases their mental pressure and economic burden. In recent years， the potential role of dietary therapy in the treatment of FGIDs has attracted more and more attention. Increasing the intake of dietary fiber can prevent human gastrointestinal diseases and maintain gastrointestinal health. This paper reviews the research progress of dietary fiber in the prevention and treatment of FGIDs， we aim to provide new dietary therapy strategies for the prevention and treatment of FGIDs.

Abstract:Milk fat globules (MFG) are secreted by mammalian glands and consist of a triacylglycerol core surrounded by a triple membrane structure， namely milk fat globule membrane (MFGM). MFGM is composed of a complex mixture of proteins， lipids， vitamins and minerals. According to reports， MFGM can promote brain development， protect human immune function and promote the growth of intestinal microbes and many other positive effects. Nowadays， with the continuous innovation of production technology， some of the biologically active proteins and lipids in MFGM can be enriched by purification， and then added to infant formula milk powder to make its nutrient content closer to breast milk. Mothers who cannot directly breastfeed their children provide suitable options. Therefore， this article aims to provide a scientific basis for reducing the difference between the nutritional requirements of infant formula and infants and young children by introducing the main components， sources and functions of milk fat globules and milk fat globule membranes and their effects on infants and young children's health.

Abstract:Lactic acid bacteria are commonly used in fermented foods， which play important roles in different activities， such as maintaining the micro-ecological balance， regulating the host immunity and preventing or treating diseases as probiotics. Surface layer protein (SLP) is the major adhesin on the surface of lactic acid bacteria， which plays a significant role in the relationship between bacterial phases and microenvironment. In this paper， SLP of lactic acid bacteria was explored and its functions were summarized， focusing on the effects of support and protection on bacterial cells； recognition and adhesion to the cells； inhibition of pathogen invasion； and host immunoregulation. In addition， the application of SLP in biotechnology， nanotechnology and vaccine research were elaborated in order to provide a basis for further research and development.

Abstract:In recent years， Pickering emulsion(PE) has become a hot topic in food industry. There are more and more researches on Pickering emulsion which is stabilized by animal protein (milk， meat and egg protein). This paper reviews the factors affecting the stability of protein-based Pickering emulsion， the kinds of animal proteins that can form Pickering emulsion， and its application in food industry. This paper provides reference for the preparation of Pickering emulsion based on animal protein stability， and can expand its application in food field.

Abstract:Gas chromatography-ion migration spectrometry (GC-IMS) is one of the newly developed volatile components detection technologies in recent years， and its application in the analysis of food volatile components is gradually expanding. In order to understand the research status of GC-IMS technology in the field of aquatic product processing and storage， this paper expounds the principle and characteristics of GC-IMS technology by analyzing relevant domestic and foreign literature reports， and focuses on its application progress and development trend in the field of aquatic product processing. The results showed that GC-IMS could determine product freshness， product shelf life， variety quality， grade classification， processing technology optimization and origin identification by detecting volatile substance changes. The application of GC-IMS technology in aquatic product processing is developing from a single technology to a joint application direction with electronic nose， GC-MS and olfactory instrument， which can represent the profile information of volatile substances in aquatic products from multiple angles and provide technical reference for guiding aquatic product processing and storage as well as quality control.

Abstract:Trans Fatty Acids (TFA) are mainly derived from hydrogenated vegetable oils and ruminant foods (synthesized by biological hydrogenation in rumen). The intake of total TFA in human diet is closely related to the increase of cardiovascular metabolic disease risk factors and the development of cardiovascular disease. However， the effects of the industrial TFA (iTFA) and the ruminant TFA (rTFA) on cardiovascular metabolic disease risk factors are still controversial. In view of this， the latest research results in this field in China and abroad are reviewed in this article. The effects of the intake of iTFA and rTFA on the risk factors of cardiovascular metabolic diseases in adults were analyzed systematically based on the comprehensive consideration of gender and age of human subjects， TFA intake， and food nutritional composition， etc. The results showed that the intake of the two types of TFA would resulted in an increase of the level of metabolic risk factors of cardiovascular disease， but the effects of rTFA on metabolic risk of cardiovascular disease were higher than those of iTFA， and the effects of rTFA were also higher for women than for men. Additionally， the risk of cardiovascular metabolic diseases was related not only to the source of TFA， but also to gender of human subjects， TFA intake， and their dietary structure. Therefore， the relationship between the intake of TFA and the risk of cardiovascular diseases under different populations and different dietary models should be further studied， which would provide scientific evidences for the establishment of acceptable daily intake of TFA for Chinese residents.

Abstract:Human milk oligosaccharides (HMOs) constitute the third most abundant solid component in human milk and play a crucial role in establishing distinctive intestinal flora and bolstering immunity in infants and young children. The discovery， production， and application of HMOs hold significant importance in enhancing the health of certain populations and nutritional requirements， thereby benefiting society's overall well-being. HMOs have received regulatory approval and/or commercial availability in over 100 countries and regions. The primary method employed for their production involves microbial fermentation， resulting in HMO structures that are identical to those found in breast milk. Extensive animal toxicology experiments and clinical trials have confirmed the safety of HMOs for use in infant formula food. To foster industrial progress in the development of high-quality infant formula， food for special medical purposes and other related fields in China， as well as to cater to the nutritional and health needs of a more extensive consumer base， the relevant experts in academic and industrial circles were organized by Chinese Institute of Food Science and Technology to form this consensus after extensive discussions through enquiries， literature retrieval and seminars， which promotes the legal use of HMOs in China's food industry.