Chemical hazards in foods have become a global public health challenge with the widespread use of chemicals in food processing. Currently, the effects of chemical exposure on human health are usually assessed by relying on complex and invasive assays for physiological and tissue parameters. As “the inhabitant” in the digestive tract, the gut microbiota has been the subject of numerous studies in recent years that suggest a possible link to food hazards. Changes in the abundance and function of the gut microbiota in response to foodborne contaminants may have the ability to determine the potential risk of food hazards. Non-invasive assays for the gut microbiota, a “microbial organ” sensitive to food safety hazards, have great potential for application in the safety risk assessment of chemical hazards in foods. In addition, the gut microbiota metabolizes and transforms certain chemicals and can also influence the toxicity and bioavailability of chemicals by modulating the host’s immune system, barrier function and metabolic pathways. Therefore, understanding the interaction between the gut microbiota and food hazards is important for assessing food safety and developing effective intervention strategies. This article reviews the applications, advantages, limitations and challenges of gut microbiota research models and omics technologies in the safety risk assessment of chemical hazards in foods. It aims to provide a scientific basis for the monitoring and risk assessment of food hazards and to provide new insights into the application of gut microbiota research models and omics techniques.

The hypolipidemic effect of egg white hydrolysate (EWH), which was prepared using peptidase 433P, in high-fat diet-fed mice was evaluated using simvastatin and commercially available vinegar-egg hydrolysate as positive controls. The results demonstrated that EWH markedly inhibited body mass gain, regulated dyslipidemia, reduced hepatic lipid abnormalities and inflammatory damage, and inhibited the degeneration and formation of adipocytes and the accumulation of triglycerides in adipose tissue. Afterwards, the effect of gastrointestinal digestion on the blood lipid regulatory activity of EWH was studied. The results showed that the inhibitory effect of EWH on the solubility of cholesterol-rich micelles decreased after gastrointestinal digestion, while the bile acid binding capacity and pancreatic lipase inhibitory activity showed no significant change. At last, three putative pancreatic lipase inhibitory peptides with amino acid sequences of LWVPSVY, YPILPEYLQ and WNIPIGTL were identified by mass spectrometry (MS) and molecular docking. Each of these peptides could interact with the receptor protein 1ETH through hydrogen bonds, electrostatic interactions and hydrophobic interactions, thus exerting hypolipidemic activity.

High internal phase Pickering emulsions (HIPPEs) stabilized by food-grade solid particles exhibit excellent biocompatibility, structural stability, and potential for delivery of functional factors, making them suitable for developing personalized, nutritionally rich high-value products. In this study, polysaccharide-based HIPPEs were stabilized by the interaction of β-cyclodextrin (β-CD) and chitosan hydrochloride (CHC). The results demonstrated that when 0.4% CHC was added and the aqueous phase pH was 4.0, β-CD and CHC formed a densely cross-linked interpenetrating network, driven by electrostatic repulsion and spatial hindrance. This network stabilized the HIPPE droplets, resulting in uniform droplet sizes with the smallest size of approximately (26.35 ± 8.83) nm. The HIPPEs effectively co-loaded hydrophilic (egg white peptide CYST) and hydrophobic (curcumin, Cur) bioactives, which enhanced the bioavailability of CYST and Cur to 94.83% and 75.93%, respectively. Moreover, the presence of multiple hydroxyl groups and binding sites in CYST and Cur facilitated the assembly of molecules at the interface into a three-dimensional network membrane, thus improving the stability of the emulsion. This study provides a reference for constructing functional polysaccharide-based HIPPEs and expanding their application in the food, cosmetic and coating fields.

Lysozyme, as one of the major proteins in egg white, has been widely used in the food, medicine and aquaculture fields due to its rich content and excellent antibacterial activity. Despite its notable efficacy against Gram-positive bacteria, lysozyme exhibits a lower sensitivity to Gram-negative bacteria, hindering its broader industrial application. In addition, the antibacterial activity of egg white lysozyme is affected by complex application environments and its duration of action. To bolster its antibacterial power, lysozyme is modified through various methods, including physical, chemical and biological modifications. This article presents a comprehensive review of the recent literature on the antibacterial properties of egg white lysozyme from four aspects: extraction and purification, antibacterial mechanism, modification techniques and application. It aims to shed new light on the molecular mechanism behind lysozyme’s antibacterial action in order to maximize the application value of egg white lysozyme and to provide a theoretical foundation for expanding its application in various industries.

Egg yolk is a complex supramolecular system composed of diverse proteins with high nutritional value and outstanding functional characteristics. Cryopreservation is commonly used in the food industry as an effective way to prolong egg yolk shelf life and improve transportation convenience. However, low temperature induces the aggregation of protein in egg yolk, resulting in egg yolk gelation and consequently reduced fluidity and solubility, affecting the functional properties of egg yolk, which are not conducive to the application of egg yolk in food processing. This article introduces the composition, structure and functional characteristics of egg yolk as well as the causes of egg yolk freezing and the mechanism of egg yolk gelation, and discusses the effect of egg yolk gelation induced by freezing on egg yolk quality. This review focuses on the physical, chemical and biological pretreatments for inhibiting protein aggregation during egg yolk, which is of guiding significance for inhibiting egg yolk gelation induced by freezing and for improving the quality of frozen egg yolk.

This study compared the effects of chemically synthesized folic acid and natural folic acid derived from duck egg yolk on health outcomes in pregnant mice induced by lipopolysaccharide (LPS) and their protective effects against neural tube defects in fetal mice. By observing the growth and appearance of fetal mice as well as assessing folate digestion and absorption in pregnant mice, redox homeostasis, and placental health, differences in the absorption of folates from different sources and their effects on oxidative stress levels in pregnant mice were explored. Evaluation of neural tube development in fetal mice, neural tube-related protein expression, antioxidant levels and inflammatory cytokine expression was conducted to analyze the potential of folate sources in preventing fetal neural tube defects and regulating inflammation levels in the body. The results demonstrated that both synthetic and egg-derived folic acids effectively improved the placental health of pregnant mice, with the latter being more effective in reducing LPS-induced damage in a dose-dependent manner. Egg-derived folate regulated the development of neural tube cells in fetal mice in a positive feedback manner, balanced the levels of superoxide dismutase, catalase, and glutathione peroxidase in the brain of fetal mice, and maintained the relative mRNA expression levels of IL-6, IL-1β, MCP-1, iNOS, and TNF-α in a healthy balance. High-dose egg-derived folate significantly increased the expression of neural cell adhesion molecule 1 (NCAM1), a protein associated with promoting neural tube development, demonstrating good potential for preventing neural tube defects and inhibit inflammation. These results underscore the importance of egg-derived folate for preventing neural tube defects and regulating inflammation in the body, providing a new theoretical and practical basis for developing the health benefits of food-derived folate.

The primary proteins in chicken egg white are glycoproteins, which generate substantial glycopeptides in the digestive tract following gastrointestinal digestion. The structures of the glycopeptides have yet to be identified and elucidated. In this study, chicken egg white was digested by trypsin, and N-glycopeptides were enriched from the hydrolysate by hydrophilic interaction chromatography and O-glycopeptides by retain AX chromatography combined with AminoLink resin adsorption. The structures of these glycopeptides were analyzed by liquid chromatography-mass spectrometry (LC-MS), and their potential intestinal effects were explored by bioinformatics analysis. Mass spectrometry analysis identified 1 720 N-glycopeptides from 49 N-glycoproteins and 565 O-glycopeptides from 29 O-glycoproteins. Glycopeptides derived from ovomucin were the most diverse, including 490 N-glycopeptides and 216 O-glycopeptides. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that sialylated N-glycoproteins were mainly involved in interleukin-17 signaling pathway and ferroptosis, while sialylated O-glycoproteins were mainly involved in cholesterol metabolism, vitamin digestion and absorption, the hypoxia-inducible factor-1 signaling pathway and the renin-angiotensin system. This study provides crucial structural information for further research on the potential effects of egg white glycopeptides on the intestinal tract.

This study aimed to develop an eco-friendly and efficient low-sugar marination technology for making sugar-shelled marinated eggs. Low-sugar sugar-shelled marinated eggs were prepared by partially replacing sucrose with xylitol under the assistance of high intensity ultrasound (HIU) treatments at different power levels (100, 200 and 300 W). The effects of HIU treatments on the gel properties, structural changes and sensory attributes of sugar-shelled marinated eggs were systematically investigated. The results showed that HIU treatment at 100 W significantly improved the cohesiveness and water-holding capacity of proteins in low-sugar marinated eggs, and significantly increased its hydrophobicity and digestibility, while HIU treatment at 200 W increased the zeta potential and β-fold content of the yolk, disrupted the cross-linking structure of protein molecules, and facilitated the formation of loose and porous structure. Moreover, the contents of aromatic substances and nitrogen oxides in marinated eggs was increased under 200 W HIU treatment, and the flavor quality was enhanced. This study provides a theoretical basis for the innovative development of marinated egg products and the application of HIU technology in food processing.

While Hen’s egg is nutritious and has versatile functional properties, liquid eggs are gradually becoming an alternative to shelled eggs due to the fragility of shelled eggs, its difficulty of transportation and storage, and safety problems such as foodborne microorganisms vehicled by shelled eggs. Currently, thermal pasteurization is mainly used to enhance the overall safety and extend the shelf life of liquid eggs. However, the thermal susceptibility of egg proteins leads to inadequate sterilization using traditional thermal treatments; for instance, sterilized egg proteins can be stored for only 14–21 days at 4 ℃. Additionally, the functional properties of liquid eggs can be negatively impacted, which is manifested by reduced emulsifying, foaming and gelation properties. This significantly hinders the advancement of the liquid egg industry. In view of the current situation, this article systematically examines recent advances in the effects of emerging thermal processing techniques, physical and biochemical non-thermal processing techniques and storage methods, singly and in combination, on enhancing the sterilization of liquid eggs and on maintaining and enhancing its functional properties, with a focus on the underlying mechanisms. Moreover, the potential of these techniques for industrial application is discussed. It is hoped that this review will provide theoretical guidance for processing technology innovation, product quality improvement and industrial production and application of liquid eggs.

A neutral polysaccharide (BPN1) was obtained from blueberry by citric acid-assisted extraction followed by purification through cellulose DEAE-52 and Sephadex G-100 column chromatography. The average weight molecular mass (mw) of BPN1, as determined by high-performance size exclusion chromatography with multi-angle laser light scattering (HPSEC-MALLS) detection, was 2.991 × 104 Da, the polydispersity index (PDI) was 1.163, and the molecular mass distribution ranged narrowly. Monosaccharide composition analysis performed using 1-phenyl-3-methyl-5-pyrazolone derivatization followed by high performance liquid chromatography (HPLC) showed that BPN1 was mainly composed of glucose, galactose, xylose and araban. The glycosidic bond configuration and linkage of BPN1 were analyzed by infrared spectroscopy and gas chromatography-mass spectrometry (GC-MS) after methylation. Combining the obtained results with two-dimensional nuclear magnetic spectroscopy (NMR) analysis, it was inferred that the polysaccharide was composed of a backbone chain of 1→4 linked dextran, some of which were substituted at position C6 by araban, xylose and galacto-oligosaccharide. The in vitro antioxidant assays showed that BPN1 had stronger scavenging capacity against 1,1-diphenyl-2-picrylhydrazyl, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) cation and hydroxyl radicals than hot water-soluble blueberry polysaccharide. The antibacterial test showed that the minimum inhibitory concentration (MIC) of BPN1 against Staphylococcus aureus and Escherichia coli was in the range of 2.5 to 5 mg/mL, and it exerted antibacterial activity against S. aureus and E. coli by destroying the cell membrane. This study provides a basis for the structural analysis, development and utilization of blueberry polysaccharides.

The mechanism of α-glucosidase inhibition by theaflavin-3,3’-digallate (TFDG) was analyzed using enzyme inhibition kinetics, multi-spectroscopies and molecular docking. The results indicated that the inhibition was reversible and displayed a mixed type of competitive and non-competitive inhibition. TFDG quenched the intrinsic fluorescence of α-glucosidase by forming a complex with it. Thermodynamic parameters suggested that the binding was a spontaneous, endothermic and entropy-increasing process, mainly driven by hydrophobic interactions. The binding enhanced the hydrophobicity near Tyr residue and the polarity around Trp residue, reducing the contents of α-helix, β-sheet and β-turn. Molecular docking revealed that TFDG bound in close proximity to the enzyme’s active site, engaging in two hydrophobic interactions with Phe450 and Trp406 residues, respectively, as well as forming three hydrogen bonds with amino acid residues Asp203, Phe450 and Gln603, respectively. This study provides evidence for the potential of TFDG as a feasible candidate functional factor for the treatment of diabetes.

The aim of this study was to investigate the anti-inflammatory potential and molecular properties of sturgeon (Acipenser schrenckii) milt peptide (SMP). SMP was obtained from alkali-extracted protein from sturgeon milt by enzymatic hydrolysis and purification, and its inhibitory effect on nitric oxide (NO) and bovine serum albumin (BSA) denaturation was evaluated. Then, the molecular mass, secondary structure, crystalline structure, proton peak distribution and amino acid sequence were determined by various spectroscopies, and based on the obtained results, the anti-inflammatory activity of amino acid sequences was predicted. The results showed that at a concentration of 10 mg/mL, SMP inhibited NO and BSA degradation by 45.33% and 60.34%, respectively, which was significantly more effective than sturgeon milt protein (P < 0.05). Basic and hydrophobic amino acids accounted for 37.45% and 36.77% the total amino acids of SMP, respectively, with arginine accounting for the highest proportion (16.28%). The molecular masses of SMP were concentrated in the range of 206–1 040 Da, which mainly showed an irregular amorphous structure and exposed more hydrophobic groups in aqueous solution. SMP contained many short peptides, including MPY, YWH, YPY and VPPL, and these peptide sequences had anti-inflammatory properties. In summary, SMP has potential anti-inflammatory activity and possesses the potential for further development and application as a promising source of natural anti-inflammatory peptides.

The purpose of this study was to explore the effect of freeze treatment on the binding characteristics of fillets to flavor substances in fish soup with pickled mustard greens. The study focused on the effects of freeze-thaw treatment and freeze storage on the physicochemical properties of snakehead myofibrillar protein and its binding characteristics to hexanal, octanal, linalool and myrcene. The results showed that after 7 days of storage, the solubility of myofibrillar protein decreased by about 26% in the freeze-thaw group. Compared with the freeze storage group, the oxidation degree and tertiary structural changes of myofibrillar protein were higher and more soluble aggregates were formed in the freeze-thaw group. The solubility of myofibrillar protein decreased by about 33% in the freeze storage group, which showed a more significant decrease compared to the freeze-thaw treatment (P < 0.05), resulting in more insoluble aggregates. The major force for the aggregation of myofibrillar proteins after freezing was non-covalent bonding. Molecular docking results indicated that linalool, hexanal and octanal could bind to myofibrillar proteins through hydrophobic interactions and hydrogen bonds, while the major driving force for the binding of myrcene to myofibrillar proteins was hydrophobic interaction. Freeze treatment reduced the binding capacity of hexanal and octanal to sulfhydryl groups in myofibrillar proteins through hydrogen bonds, improved the surface hydrophobicity of myofibrillar proteins, but increased the binding ability of myrcene and linalool to myofibrillar proteins. Freeze-thaw treatment increased the binding capacity of myofibrillar proteins to myrcene compared with freeze storage treatment. The results of this research provide a theoretical basis and reference for flavor control of frozen prepared fish soup with pickled mustard greens.

In this study, changes in the textural properties, dielectric properties, cell wall polysaccharide content and microstructure of yellow peach blocks were investigated after osmotic dehydration (OD) treatment with binary/ternary osmotic solutions containing sucrose and maltitol. Meanwhile, changes in the soluble sugar content were determined by 1H nuclear magnetic resonance (1H NMR) spectroscopy. Our aim was to clarify the synergistic effect of maltitol and sucrose on improving the properties of yellow peach blocks during OD treatment. Compared to the control group, The hardness, chewiness and adhesiveness of yellow peach blocks treated with a ternary osmotic solution with a 1:4 ratio of sucrose to maltitol (SM14) were significantly reduced. OD resulted in a significant decrease in the impedance (Z) and effective resistance (Rs) as well as a significant increase in the electrostatic capacity (Cs) of yellow peach blocks, suggesting that OD could affect peach pulp cell properties by acting on cell wall polysaccharides. 1H NMR results showed that OD with ternary osmotic solutions significantly reduced the sucrose content in peach fruit block tissue; for the SM14 group, the signal intensity of sucrose and maltitol were 19 803.9 ± 156.00 and 54 934.9 ± 1 239.11, respectively. Meanwhile, the contents of water-soluble pectin (WSP) and CDTA-soluble pectin (CSP) in the SM14 group were increased to (26.63 ± 1.80) mg/g and (21.59 ± 0.71) mg/g, respectively, while the content of Na2CO3-soluble pectin (NSP) was decreased to (27.24 ± 0.46) mg/g compared to the control group. Microstructure analysis showed that round and relatively intact cells with low degree of collapse and a significant increase in cell wall thickness were observed in the SM14 group, demonstrating sucrose and maltitol synergistically protect peach pulp cells. Therefore, ternary osmotic solutions of sucrose maltitol could effectively ameliorate the quality deterioration of yellow peach blocks caused by binary osmotic solutions, broadening the application of sugar alcohol.

This study examined the effects of egg white protein (EWP) and konjac glucomannan (KGM) on the digestion and fermentation properties of shrimp (Trachypenaeus curvirostris) surimi gel (SSG) using in vitro models. The results showed that the in vitro protein digestibility of the SSG-EWP group increased first and then decreased with the increase in EWP concentration, and EWP increased the generation of peptides during SSG digestion. SSG with 4% added EWP had the highest in vitro digestibility, while neither the in vitro protein digestibility nor the peptide release of SSG was significantly influenced by KGM (P > 0.05). EWP and KGM increased the contents of essential amino acids in the digestion products of SSG. Antioxidant assay showed that EWP improved the Fe2+ chelating capacity of the digestion products, but decreased the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity. KGM increased the antioxidant activity of the digestion products in terms of both Fe2+ chelating capacity and DPPH radical scavenging capacity. Furthermore, gut microbiome study revealed that EWP played a more positive role in maintaining gut microbial diversity and regulating beneficial bacteria than KGM. Clusters of Orthologous Groups (COG) metabolic pathway analysis indicated 24 major metabolic pathways of intestinal microbes, mainly involving the transport and metabolism of carbohydrates, amino acids and other substances. This study provides technical guidance for the preparation of high-quality T. curvirostris surimi gel.

The aim of this study was to determine the interrelationship between umami peptides and microorganisms in traditional fermented sea bass and to explore the inhibitory effect of umami peptides on bitterness. Thirty-eight umami peptides were identified and predicted from traditional fermented sea bass using peptidomics combined with machine learning techniques, and the results of macrogenomic annotation indicated that a total of 51 microbial genera and 7 proteases were involved. Rhodococcus, Staphylococcus, Clostridium, Thiothrix, Pseudomonas and Achromobacter might play key roles in the formation of the flavor peptides in fermented sea bass. Molecular docking results showed that umami peptides EEEVVEEVE, DEEYPDL and DEEYPDLS could bind to the bitter taste receptor (TAS2R14), and their binding cavities were consistent. The interaction between the three peptides and TAS2R14 was mainly through hydrogen bonding, and the key binding sites of these peptides were SER265, SER69, SER65 and THR86. The electronic tongue results showed that all three umami peptides had a significant inhibitory effect on bitterness. This study provides a new idea to study the interaction between fish-derived umami peptides and bitterness.

The aim of this study was to achieve efficient expression of mannanase CtMan26 from Chaetomium thermophilum in Pichia pastoris and to investigate the enzymatic properties of CtMan26 and its potential in the preparation of mannooligosaccharides (MOS). The mannanase CtMan26 contained a total of 448 amino acids and consisted of the family 35 carbohydrate-binding module (CBM35), Linker and the catalytic domain module of the GH26 family. Asp-395 and Leu-396 in the catalytic domain and Leu-100 in the auxiliary module of CBM35 were subjected to multiple hydrophobic forces and could form multiple hydrogen bonds with amino acids in the Linker. Recombinant enzyme CtMan26 was expressed with N-glycosylation modification. CtMan26 showed an apparent molecular mass of about 55 kDa. The optimum temperature of the recombinant enzyme was 55 ℃, and the optimum pH was 5.0. The enzymatic activity was maintained at more than 90% of its original value after being incubated at 50 and 60 ℃ for 1 hour, and it showed good stability at pH ranging from 4.0 to 12.0. The specific activity of CtMan26 was 23.15 U/mg, and its Km and Vmax values were 4.75 mg/mL and 27.17 μmol/(min·mg), respectively, when konjac glucomannan was used as the substrate. MOS prepared with the recombinant enzyme mainly consisted of mannose (14.2 mg/L), mannose disaccharides (20.1 mg/L), mannose trisaccharides (6.1 mg/L) and mannose tetrasaccharides (2.5 mg/L). The MOS exhibited good antioxidant capacity, which scavenged (90.80 ± 0.65)% of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, (80.7 ± 1.07)% of 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical, (69.10 ± 1.10)% of hydroxyl radical and (76.7 ± 3.14)% of superoxide anion radical at 2.4 mg/mL concentration. Meanwhile, the MOS had obvious prebiotic properties, which could inhibit the growth of Escherichia coli and promote the growth of the beneficial bacteria Pediococcus pentosaceus and Lactobacillu plantarum the effect being more pronounced with increasing concentration and incubation time. In conclusion, the recombinant mannanase CtMan26 has good enzyme properties and therefore has potential application in the preparation of MOS.

This study investigated the differences in the physicochemical indexes, volatile flavor substances and microbial community composition of three different colored Daqu (black, yellow and white). Physicochemical analyses showed that the acidity, moisture content and saccharifying power of black Daqu were intermediate between those of yellow and white Daqu, white Daqu had the highest saccharifying power, fermenting power, and esterifying power, and yellow Daqu contained the highest starch content. Flavor substance analysis indicated significant differences in the contents of ethyl caproate, ethyl acetate, phenylethyl alcohol, 1-hexanol and furfural among the three types of Daqu. Microbial community structure analysis revealed that Bacillus and Scopulibacillus were the dominant bacteria, and Thermomyces and Thermoascus were the major fungi in all three types of Daqu. Redundancy analysis (RDA) suggested that Bacillus and Thermomyces had a positive correlation with fermenting power, esterifying power and saccharifying power. Spearman correlation analysis showed that Scopulibacillus, Virgibacillus and Aspergillus were positively correlated with most key flavor compounds. This study provides reference data for the rational application of Daqu in the production of Jiang-flavor Baijiu and is of great value for the standardization of Jiang-flavor Baijiu production.

This study investigated the inhibitory effect of antimicrobial peptide from Paenibacillus ehimensis on the biofilms of Candida albicans by the microdilution and time-kill curve assays. Microscopic observation was conducted to assess the impact of the peptide on the formation of C. albicans germ tube and hyphae. Additionally, the 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay was employed to investigate the influence on the formation of C. albicans biofilms, pre-formed biofilms, and the clearance rate of mature biofilms. Fluorescent probes were utilized to observe the alteration in the structure of biofilms and the status of intracellular fungal entities. The number of viable cells in biofilms was measured by the spread plate method, and real-time polymerase chain reaction (PCR) was employed to determine the expression levels of genes associated with biofilm formation. The results showed that the minimum inhibitory concentration of the antimicrobial peptide against C. albicans was 8.28 AU/mL. This peptide reduced the rate of germ tube formation in C. albicans, and prevented the formation of hyphae, making it exist in the form of yeasts. Furthermore, the antimicrobial peptide influenced both the formation and eradication of biofilms and disrupted the structural integrity of biofilms after a short duration, leading to damage and even death of C. albicans, and reducing cell counts in biofilms. The antimicrobial peptide reduced the expression levels of multiple genes related to biofilm formation (such as ALS1, ALS3, HWP1, EFG1, ECE1 and UME6), therefore inhibiting biofilm formation. The above findings demonstrated that antimicrobial peptide effectively inhibited the biofilm formation, mature biofilm clearance and the expression of biofilm-forming genes in C. albicans. This study lays a theoretical foundation for the development of novel antimicrobial agents against C. albicans and provides a basis for the prevention and control of foodborne pathogen contamination to ensure food quality and safety.

The objective of this study was to investigate the ameliorative effect and potential mechanism of Cistanche deserticola polysaccharides (CDPs) on diabetic nephropathy (DN) in mice. The DN mouse model was established by high-fat diet (HFD) feeding combined with intraperitoneal injection of streptozotocin (STZ). Thirty-six C57BL/6N male mice were randomly divided into six groups (n = 6 each). All groups were orally administered with distilled water (control and model), dapagliflozin or CDPs for 4 weeks. Changes in physiological indices, renal function, inflammatory factors and the intestinal microbiota were assessed. The results showed that CDPs significantly improved the general condition and attenuated the renal histopathological changes, and reduced the levels of blood glucose, urinary protein and inflammatory factors in DN mice. Additionally, CDPs affected the balance of intestinal microbiota, increased the abundance of beneficial bacteria and decreased potential pathogenic bacteria, which in turn improved intestinal barrier function. CDPs also inhibited the activation of the Toll-like receptor 4/nuclear factor-κB (TLR4/NF-κB) signaling pathway and reduced the release of lipopolysaccharide (LPS). In conclusion, CDPs exhibit an ameliorative effect on DN in mice by affecting the intestinal microbiota and inhibiting inflammatory signaling pathways. This finding offers new insights into the treatment of DN.

The protective effect and possible mechanism of corn peptide on alcohol-induced injury in PC12 cells were explored. A cell model of alcohol-induced injury was established, and different concentrations of corn peptide were screened. Oxidative stress indicators such as glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA), inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and nuclear factor-κB (NF-κB), neurotrophic factors such as nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and synaptic plasticity-associated proteins including postsynaptic density-95 (PSD-95), growth-associated protein-43 (GAP-43) and synaptophysin (SYN)) in PC12 cells pretreated with corn peptide were determined using an enzyme-linked immunosorbent assay kit. The optimal alcohol concentration for inducing cell damage was determined to be 400 mmol/L based on cell viability and morphological changes, and three concentrations of corn peptide, 25 (low), 100 (medium), and 400 (high) μg/mL, were selected for this study. The experimental results showed that corn peptide at all three concentrations significantly increased the survival of alcohol-injured PC12 cells, increased the levels of GSH and SOD, inhibited MDA production, reduced the levels of TNF-α and IL-6, inhibited the increase in NF-κB levels induced by alcohol, increased the levels of NGF and BDNF, and elevated PSD-95 and GAP-43 levels, but had no regulatory effect on SYN levels. In conclusion, corn peptide has a protective effect on alcohol-induced injury in PC12 cells, and the mechanism involves multiple pathways.

In order to investigate the effect of fermentation using whole kiwifruit on the flavor profile of kiwifruit wine, the flavor profiles of kiwifruit wine fermented from whole and peeled kiwifruit were analyzed by gas chromatography-ion mobility spectrometry (GC-IMS), headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and sensory evaluation. The results showed that a total of 124 volatile compounds were detected in the two wine samples by the combined use of GC-IMS and HS-SPME-GC-MS, which were much more than those detected by single techniques. This suggests that the combination of multiple techniques provides more comprehensive and systematic flavor characterization of kiwifruit wine than their separate use. Compared with the wine made from peeled kiwifruit, the one made from whole kiwifruit contained 13 more eater and aldehyde compounds and four less acids and ketones. Moreover, the relative contents of ethyl decanoate, n-octanal, isoamyl hexanoate, 2-methylethyl acetate, ethyl valerate, butyl valerate, and cis-rose oxide were significantly higher in whole kiwifruit wine (P < 0.05) while the relative contents of 3-octanol and 2,6-dimethylpyridine were significantly lower (P < 0.05), compared with that made from peeled kiwifruit. Sensory evaluation results showed that whole kiwifruit wine had higher overall scores with a prominent characteristic aroma, which was superior to peeled kiwifruit wine in terms of overall balance. In summary, this study showed that fermentation using whole kiwifruit improved the flavor quality of kiwifruit wine. This finding provides a theoretical basis and data support for the optimization of the kiwifruit wine brewing process and quality improvement.

In order to explore the differences in the aroma components of baked green tea harvested in different seasons, the composition and content of volatile components in spring and autumn green tea processed from three major tea cultivars in Zhejiang province were systematically analyzed via stir bar sportive extraction (SBSE) combined with gas chromatography-mass spectrometry (GC-MS). Then, key differential volatile components and key aroma-active components were selected by multivariate statistics and odor activity value (OAV) analysis. Results showed that a total of 105 volatile components were identified in spring and autumn green tea, and alcohols, esters and ketones accounted for more than half of the total number. Through principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA) and significance analysis, 38 compounds such as phytol, 1-octanol and 1-octen-3-ol were found to be the key compounds with statistical differences in spring and autumn green tea (P < 0.05). Combining the results of quantitative analysis and OAV, phytol, hexanal, nonanal, 1-octen-3-ol, octanal and trans-β-ionone were identified as the key aroma active components in baked green tea (OAV > 1). The concentration of phytol in autumn tea samples (967.65 ng/mL) was significantly higher than that in spring tea samples (370.82 ng/mL). It might be related to the sufficient chlorophyll reserve in fresh tea leaves harvested in autumn. However, the concentrations of hexanal and other components were generally higher in spring tea, which might be related to the seasonal changes of enzyme activities related to the formation of fatty acids or carotenoid derivatives.

In this study, gas chromatography-olfactometry-mass spectrometry (GC-O-MS) combined with odor activity value (OAV) was used to analyze the key odorants of clean aroma-type Xinyang Maojian (XYMJ) green tea. The results of aroma extract dilution analysis (AEDA) showed that 48 volatile compounds were obtained from XYMJ green tea infusion by solvent-assisted flavor evaporation (SAFE) and headspace-solid phase microextraction (HS-SPME). Twenty-two volatile compounds with flavor dilution (FD) factor ≥ 27 were identified. Among these, dihydroactinidiolide showed the highest FD factor (6 561), followed by vanillin (2 187), coumarin (729), 2-phenylethanol (729), hexanal (243), 4-hydroxy-2,5-dimethylfuran-3(2H)-one (243) and δ-decalactone (243). Through quantitative analysis, we identified 17 key odorants with OAV > 1, including (E,Z)-2,6-nonadienal, dimethyl sulfide, 3-methylbutanal, geraniol, (E)-β-ionone, linalool, 6-methyl-5-hepten-2-one, (E,E)-2,4-heptadienal, hexanal, 2-methylbutanal, jasmone, nonanal, δ-decalactone, γ-hexalactone, coumarin, δ-jasmolactone and indole. The OAV values indicate that these key odorants make important contributions to the aroma quality of clean aroma-type XYMJ green tea.

To deeply explore and develop their nutritive values and functions, the proteins and metal elements in two kinds of Macrocybe lobayensis (ML), TG505 and Grand Canyon ML were determined and analyzed. Protein fingerprints were obtained using phenol extraction and two-dimensional electrophoresis (2DE), and highly expressed proteins were selected. The enzymatic hydrolysates of highly expressed proteins were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Functional analysis of these proteins was carried out using bioinformatics tools. The contents of metal elements in the two kinds of mushrooms were determined by inductively coupled plasma mass spectrometry (ICP-MS). The results showed that 33 highly expressed proteins were identified from each kind of ML, which were involved in the growth, development, genetics, stress resistance, stress response, pharmaceutical activity and other functions of ML. For both kinds of ML, the major metal elements were K, Mg, Mo, Ca, Al, and Fe in decreasing order. The present study not only provides guidance for further exploitation and utilization of ML, with both medicinal and culinary uses, but also is of reference significance for the research and development of tropical edible mushrooms in Hainan.

The objective of this study is to compare the effects of different fermentation processes with lactic acid bacteria (LAB) on the chemical constituents of mulberry leaves and to select superior LAB. The chemical components in mulberry leaves were detected by ultra-high performance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-Q-TOF-MS) and were identified by comparison with reference substances based on MS fragmentation pathways and literature information. Principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) models for discriminating different fermented mulberry leaves were built with SIMCA 14.1 software. PCA score plots, PLS-DA loading plots and variable importance in projection (VIP) values were obtained and based on them the major differential substances between before and after fermentation were determined. As a result, 41 chemical components were identified. PCA indicated a clear separation of mulberry leaves subjected to different fermentation processes. By PLS-DA, 11 chemical components with VIP values > 1, cosmetin, isorhamnetin-3-O-neohespeidoside, hyperoside, 3,4-dicaffeoyl quinine, aurantio-obtusin, salicylic acid, genistine, cyanidin 3-O-glucoside, guanosine, isoacteoside and acteoside, were selected as differential markers between mulberry leaves before and after fermentation. Based on comprehensive weighted scores, it was found that mulberry leaves fermented by Lactobacillus rhamnosus had the highest content of bioactive components. In conclusion, the chemical components of mulberry leaves changed significantly after fermentation. Flavonoids were the most important compounds to distinguish mulberry leaves fermented by different strains, and L. rhamnosus was a superior strain for the fermentation of mulberry leaves.

This study investigated the ultrasound-assisted enzymatic depolymerization of egg yolk granules and the subsequent preparation of highly soluble egg yolk granule powder. The results showed that after ultrasound-assisted enzymatic treatment at solid-to-liquid ratio of 1:12 (g/mL), the solubility of egg yolk granules increased from 8.1 to 89.7 g/100 g, the soluble protein concentration increased by 2.16 times, the average particle size decreased from 24.74 to 1.05 μm, and the dispersion stability increased markedly. When the solid-to-liquid ratio was increased to 1:9, the solubility of egg yolk granules was still as high as over 85.0 g/100 g. The solubility of depolymerized granules was 53.7 g/100 g after enzyme inactivation and sterilization. After dispersion treatment, egg yolk powder had solubility as high as 86.5 g/100 g. After heat treatment at 80 ℃ or below for 20 min, pH adjustment to 6.5–7.5, or addition of salt at levels below 2%, the dispersion solution could remain stable for 24 h. Compared with egg yolk powder, egg yolk granule powder has the characteristics of higher protein, lower fat, and lower cholesterol. The preparation technology of highly soluble egg yolk granule powder provides technical support for the industrial production and multi-scenario application of egg yolk granule powder.

Starch acetate was prepared from corn starch after ultra-high pressure (UHP) pretreatment at different pressure levels (100, 200, 300, 400, 500, and 600 MPa). The structural properties of UHP treated starch and starch acetate were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), rapid viscosity analysis (RVA) and differential scanning calorimetry (DSC). The results indicated that both UHP treatment and acetylation reaction resulted in swelling and rupture of starch granules. After UHP pretreatment, the relative crystallinity and gelatinization enthalpy of starch increased first and then decreased, reaching maximum values of 35.4% and 11.90 J/g at 400 MPa, respectively. Meanwhile, pasting parameters reached maximum values at this pressure level. After pretreatment at 600 MPa, the starch was gelatinized completely and the morphology of starch granules was destroyed. Furthermore, the crystalline structure changed from A-type to V-type. As a result, the degree of substitution and reaction efficiency of starch acetate significantly increased, reaching maximum values of 0.103 and 81.14%, respectively, when the pressure was 500 MPa. The occurrence of the maximum values might be related to the fact that the granular state was maintained despite obvious structural damage of starch granules, resulting in increased contact between starch granules and acetic anhydride. The findings of this study demonstrate that UHP pretreatment changes the structure of starch and thus helps increase the synthesis efficiency of starch acetate.

A composite beverage was made from Hericium erinaceus and yam. The effects of pasteurization, high-temperature sterilization and cold plasma sterilization on the in vitro antioxidant activity, volatile flavor composition and storage quality of the beverage were compared. The shelf-life at 4 ℃ was predicted. The results showed that the in vitro antioxidant activity of beverage processed with the three sterilization methods followed a decreasing order: cold plasma sterilization > pasteurization > high-temperature sterilization. The beverage processed with cold plasma sterilized had stronger fruity, woody and mushroom-like flavors but lighter malt- and butter-like flavors. Cold plasma sterilization caused minimum quality loss. During the shelf-life, the beverage had good color and high sensory scores. The shelf-life was 68 days at 4 ℃ compared to 137 days with pasteurization and high-temperature sterilization. The application of cold plasma sterilization to the composite beverage expands the application scope of the novel sterilization technology and provides technical support for the deep processing of H. erinaceus and yam.

A composite film was developed using pea protein (PP) as the film-forming substrate, chitosan (CS) as the film-modifying material, chlorogenic acid (CA) as the functional component, tyrosinase (Tyr) as the crosslinking agent, and glycerol as the plasticizer. The physical parameters and microstructure of the PP-CA-CS film were determined. The aim was to explore the effects of PP-to-CS ratio and the concentrations of CA and Tyr on the structure and properties of the composite film and to study the interaction between its components. The results showed that the antioxidant potential and mechanical properties of the composite film were significantly improved after the addition of CA, and Tyr catalyzed the covalent cross-linking of CA with PP and CS. With the addition of CA and Tyr, the cross-linking degree and mechanical properties were improved. At a PP-to-CS ratio of 1:1, at 20 mmol/L CA concentration and at 18 U/mL Tyr concentration, the composite film had the best mechanical properties, antioxidant properties and water vapor barrier properties. In addition, the tensile strength of the film was 130.78 MPa, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity was 69.05%. Compared with pure PP-CS film, the mechanical properties of the PP-CA-CS composite film were increased by 3.6 times, the antioxidant potential was increased by 3.2 times, and the water vapor permeability was decreased by 8%. The results of scanning electron microscopy (SEM) showed that the PP-CA-CS composite film was smooth and compact, so it had high water vapor barrier performance. No new functional groups were generated in the film formation process as demonstrated by infrared spectral analysis. Therefore, this study provides a new idea for researchers in the field of new food packaging, and offers data and theoretical support for the development of edible films.

A rapid single-tube method for the detection of peach-derived ingredients was established using recombinase-aided amplification (RAA) combined with clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated proteins (Cas)12a. Specific primers for RAA and CRISPR RNA (crRNA) were designed. The specificity, sensitivity and detection limit of the developed method were analyzed, and it was applied to commercial samples. The results showed that the method enabled rapid detection of peach-derived ingredients without the need for large-scale instruments in less than 30 minutes. No cross-contamination with other common fruit species was observed, indicating good specificity. The sensitivity of this method was 1.0 × 10-1 ng/µL, and the limit of detection was 1%. The results of detection of 20 commercial fruit juice samples by this method were consistent with those of real-time polymerase chain reaction (PCR). Therefore, the single-tube integrated RAA-CRISPR/Cas12a method has the advantages of high specificity and sensitivity, providing a new technology for rapid detection of peach-derived ingredients.

Raw Nongxiangxin Baijiu of different grades were collected during the distillation process, and their near infrared spectroscopy (NIR) data and gas chromatography-mass spectrometry (GC-MS) data were acquired. After preprocessing the NIR data through 5-point 2-fold convolutional smoothing, spectral feature wavelengths were selected using the competitive adaptive reweighted sampling (CARS) algorithm; combining Spearman’s rank correlation coefficient, maximum information coefficient (MIC) and random forest (RF) variable importance, the key flavor components (KC) identified by GC-MS affecting the grading of raw Baijiu were determined. Then, extreme gradient boosting tree (XGBoost) was applied to establish three grade identification models for raw Baijui based on NIR, GC-MS and their fused data. The results showed that the prediction accuracy of the model based on the spectral feature variables selected by CARS was 89.66%, the prediction accuracy of the model based on KC after feature selection was 94.83%, and the classification accuracy of the model based on the fused data of CARS + KC reached as high as 98.28%. This study shows that the fusion of effective feature information from GC-MS and NIR data can enable more accurate and stable grade identification of raw Nongxiangxin Baijiu than either analytical technique alone, which provides a new idea and theoretical basis for the grade identification and quality control of raw Baijiu.

Reactive carbonyl species (RCSs) are a class of active aldehydes and ketones. RCSs are formed in the body through a serious of reactions such as lipid oxidation and glycolysis as well as through lipid oxidation and the Maillard reaction during food processing. RCSs are usually kept at a low concentration level in the body, while high level of these substances can cause diseases in the body. The intake of RCSs by the human body mainly comes from processed foods. Furthermore, RCSs can induce the formation of other hazards during food processing. Therefore, controlling the formation of RCSs in foods is crucial for nutritional health. This article reviews the formation and biological activity of RCSs as well as their impacts on the formation of chemical hazards such as heterocyclic amines, advanced glycation end products (AGEs), acrylamide, and polycyclic aromatic hydrocarbons in food processing. The aim of this study is to provide a reference for the safety control of RCSs during food processing.

Flavor substances affect the sensory properties of food and consumer choices, and flavor substance analysis is crucial for improving food quality and developing new products. However, the vast amount of flavor substance data and inappropriate statistical analysis greatly limit the development of this field. Therefore, it is crucial to use new chemometrics methods, such as artificial intelligence algorithms, correctly and reasonably to obtain effective information in this field. In recent years, chemometrics methods have been widely applied in food research. In addition to dimensionality reduction, classification and regression methods, various neural network methods have also emerged in the field of food research. However, a summary of their reasonable application is lacking. Therefore, this article summarizes the statistical analysis methods available to study food flavor, including principal component analysis, linear discriminant analysis, linear regression methods such as partial least squares regression, and nonlinear methods such as fuzzy logic and artificial neural networks, explains their principles and provides application examples. This article aims to provide effective methods and ideas for further research on chemometrics in the field of food flavor.

With the emergence of social aging and the increasing emphasis on skin health, the demand in the market for active ingredients to prevent and delay skin aging is increasing. Collagen peptides have various physiological activities and great potential in delaying skin aging. In this paper, the source, preparation, structure and biological activities of collagen peptides are introduced, and the mechanisms of action of collagen peptides in delaying skin aging are summarized. Moreover, the progress made in the past decade in clinic research on oral collagen peptides in alleviating skin aging is reviewed. At present, collagen peptides have been widely applied in various fields such as foods, oral beauty drinks, health products and cosmetics. However, there are still some problems and challenges in terms of optimal intake, evaluation methods, identification and exploration of functional peptides, and interaction with other components. With the progress of production technology and the continuous deepening of research, collagen peptides with anti-skin aging activity have enormous potential and broad application prospects in food nutrition, healthy skincare, clinical therapy and medical beauty.

A variety of components with different chemical structures have been found in Baijiu at highly variable concentrations. Therefore, matrix effects is prevalent in Baijiu analysis, posing challenges to the accurate characterization and quantification of target compounds. This paper aims to summarize the influential factors, consequences and elimination/reduction pathways of the matrix effects in Baijiu analysis. It focuses on recent progress in the methods of reducing and compensating for the matrix effects, such as the application of pretreatment methods, the selection of instrumental analytical methods, matrix matching calibration and internal standard calibration. This review lays a theoretical foundation for improving the accuracy and scientific rigor of Baijiu analysis and provides theoretical support for Baijiu producers in the scientific construction of quality control indexes.

Water-holding capacity, texture and color are important indicators of fresh meat quality. In China, drip loss and textural deterioration of fresh meat are critical problems in the meat industry, causing greater quality loss than that in developed countries. Recently, researchers have identified a series of potential biomarkers for the water-holding capacity and tenderness of meat and have studied the effect of cell apoptosis on meat tenderness. However, the relationship between ferroptosis and fresh meat quality has been researched little. After slaughter, the intramuscular environment alters and ferroptosis occurs, which is characterized by the accumulation of iron, an increase in lipid oxidation and disruption of redox equilibrium. These changes are closely related to meat quality. This paper reviews the characteristics, metabolic pathways and regulatory mechanisms of ferroptosis, and the crosslinks between ferroptosis and other modes of cell death. Moreover, it elaborates on how ferroptosis affects fresh meat quality through iron homeostasis imbalance, redox imbalance and lipoperoxidation. Overall, this review provides deeper insights into the mechanism of meat quality formation during postmortem aging.

Bitter peptides derived from the hydrolysis of proteins can cause food to taste bitter and are generally deemed undesirable from the perspective of taste. However, studies have shown some bitter peptides to have bioactivities that are beneficial to human health and helpful for alleviating chronic diseases. Hence, elucidating the bitter mechanism of bitter peptides is important for improving the taste and bioactivity utilization of food. Previous studies have pointed out the factors affecting the bitterness of peptides, such as Q value, bitter amino acids, bitterness indicator motifs and spatial structure, but the universal mechanism is still unclear. Enzymatic and non-enzymatic debittering treatments have been developed for laboratory and industrial applications, among which, enzymatic debittering treatments have attracted more attention due to the high efficiency and biosafety, and animal/plant/microorganism-derived enzymes with debittering capacity or potential have been identified and reported continuously. This review comprehensively summarizes recent progress in bitter peptides, including their sources, bioactivities, identification methods, bitterness mechanism and enzymatic/non-enzymatic debittering treatments, and the common characteristics of enzymes from different sources with debittering capacity or potential. Finally, it gives an outlook on future research directions.

Grape production is an important part of the agricultural economy, which has economic and widespread social benefits. Monitoring and evaluation of grape berries during growth is an important guarantee for the production of high-quality grape berries. Traditional testing techniques are time-consuming, laborious and destructive, while non-destructive testing techniques represented by hyperspectral technology can successfully solve this problem. This paper summarizes recent progress in the application of hyperspectral technology in grape shape measurement, chemical substance detection, ripeness discrimination and defects and damage identification. It also analyzes the advantages and disadvantages of hyperspectral technology in the detection of different quality indexes, and discusses the potential of and prospects for the application of hyperspectral technology in the detection of grape quality, which is aimed at providing a reference to the research and developing non-destructive techniques for the quality detection of grape berry.

As an important way of food safety governance, the food recall system is closely related to enterprise compliance construction. Taking risk prevention as the core and fulfillment of compliance obligations as the basis, both can be used as the basis for administrative incentives. In practice, there are problems in the compliance construction of enterprise food safety governance, such as insufficient food recall motivation and insufficient government supervision methods and breadth. Government supervision assumes important supervision responsibilities in the whole food recall process. In the pre-recall stage, there is a tendency toward food quality and safety supervision, and the mid-recall stage focuses on supervising whether enterprises strictly implement the recall plan. In the post-recall stage, corresponding legal responsibilities are mainly imposed on enterprises. In light of this, for the construction of food safety compliance in enterprises, a compliance system with government supervision as the guidance should be built; administrative organs should guide enterprises to formulate compliance plans for food safety governance, correct and punish practitioners who are idle in compliance construction, and take regulatory incentives as an opportunity to stimulate enterprises’ independent compliance construction capability.