Purpose: To address the issue that laboratory methods cannot meet the need foron-site rapid testingat the grassroot level, a quick method for detecting the authenticity of meat products was established based on multienzyme isothermal rapid amplification (MIRA) coupled with lateral flow dipstick (LFD). Methods: Pig, cattle, sheep, chicken, and duck-specific mitochondrial gene sequences were selected through GenBank, and intra-species conserved and inter-species specific target fragments were compared using the DNAStar Megalign software. According to the design principles of MIRA primers and probes, target gene-specific primer and probe sets were designed and screened systematically through positive, negative and blank controls to determine the species-specific primers and probes. The reaction system, temperature, and time were optimized. Analytical figures of merit of the method including DNA extraction, sensitivity, detection limit, false positive rate and false negative rate were evaluated to verify its validity. Results: Compared with real-time fluorescent polymerase chain reaction (PCR), the average false positive rate of this method was 3.49%, and the false negative rate was 3.54%, which meets the requirements of on-site rapid testing. Conclusion: In this study, the MIRA-LFD technique was established for 5 common meats, namely, cattle, sheep, pig, chicken and duck, and its validity and feasibility were confirmed, realizing on-site rapid testing of the authenticity of meat products.

Sesame oil is one of the indispensable cooking oils in daily diets, and its quality and safety has aroused wide concern. However, the issue of sesame oil adulteration has become increasingly serious, making it urgent to guarantee the quality and safety of sesame oil. Therefore, it is important to establish an anti-counterfeiting and traceability system. In this study, a blockchain-based anti-counterfeiting and traceability system for sesame oil was designed. A ‘blockchain caching’ double storage design was proposed, which could store and cache information off-chain while synchronously storing the encrypted hash value of traceability information on-chain. In addition, a querying scheme that could connect smart contracts directly to the state database was designed to solve the problems of high data storage pressure and low querying efficiency on the blockchain network. It was verified that consumers could quickly and conveniently check the authenticity of sesame oil by scanning the QR code of a mini program, which could effectively solve the problems of data security and the authenticity of traceability information between different links in the sesame oil traceability chain, and it was successfully applied to real samples with good results.

Citri Reticulatae Pericarpium (CRP) has both culinary and medicinal uses, with high medicinal and economic value. However, CRP fraud such as mislabeling of the geographical origin, passing off, and aging time cheating has occurred frequently, which damages consumer interests. In order to ensure the safety and quality of CRP, it is urgent to establish effective techniques for its geographical origin traceability and authentication. In this article, we review recent progress on the application of metabolomics, spectroscopy, DNA analysis, elemental analysis and intelligent sensory analysis in identifying the geographical origin, variety, harvest period and aging time of CRP. Meanwhile, we compare and analyze the advantages and disadvantages of each technique, and propose the existing problems and future research priorities in the field of geographical origin traceability and authentication of CRP.

In this study, the bactericidal activity and mechanism of slightly acidic electrolyzed water (SAEW) against Campylobacter jejuni were examined. The effect of available chlorine concentration (ACC), treatment time and protein addition on the bactericidal activity of SAEW were investigated. In addition, the killing effect of SAEW on multi-generational cultures of C. jejuni was analyzed. The bactericidal mechanism was explored based on the changes in cell membrane integrity, morphology, and contents. The results showed that the inactivation of C. jejuni by SAEW was positively correlated with ACC and treatment time. Exogenous protein significantly weakened the bactericidal efficacy of SAEW. C. jejuni did not develop resistance to SAEW within ten passages. SAEW could destroy the integrity of the cell membrane. After treatment with SAEW, the cell surface was sunken, wrinkled and broken, and nucleic acid, protein and ATP leaked out from the cells, indicating that cell membrane damage may be the major reason for SAEW to inactivate C. jejuni.

In order to investigate the interaction between aloe emodin and α-glucosidase, enzyme kinetics, ultraviolet (UV) spectroscopy, infrared (IR) spectroscopy and fluorescence spectroscopy were employed to investigate the inhibitory mechanism of aloe emodin on α-glucosidase and the synergistic effect of aloe emodin in combination with acarbose was also investigated in this study. The results showed that aloe emodin had better inhibitory effect on α-glucosidase as both a non-competitive and anti-competitive inhibitor when compared with acarbose. The results of UV spectroscopy indicated that a new complex was formed through the interaction between aloe emodin and α-glucosidase. The characteristic vibrations of amide groups in the IR spectra indicated that the structural conformation of α-glucosidase changed with the addition of aloe emodin. The results of fluorescence quenching experiments showed that the endogenous fluorescence of α-glucosidase was statically quenched by aloe emodin. In addition, it was also found that aloe emodin combined with acarbose had a synergistic inhibitory effect on α-glucosidase activity. This study provides an experimental basis for the future application of aloe emodin in health foods for regulating blood glucose.

In this study, oleogels were prepared with rapeseed oil and coconut oil as oil phase and monoglyceride (MG), beeswax, rice bran wax, carnauba wax or candelilla (CLW) wax as gelling agent, and the effects of different concentrations of gelling agent (5%, 10%, 15%, and 20%) on the oil-holding capacity, textural properties and rheological properties of oleogels were investigated. The results showed that the oil-holding capacity of the oleogels prepared with 15% and more gelling agent was more than 96%; the melting characteristics of MG were most similar to those of butter, but the textual properties of oleogels prepared with a single gelling agent were not comparable to that of butter. Therefore, mixtures of MG and CLW in different proportions by mass were used to prepare oleogels with 15% oleogels and plant-based patties. The results showed that the oleogel prepared with a 3:7 mixture of MG and CLW was the closest to butter in terms of textural and rheological properties, and the resulting patty had the highest sensory quality, showing that this oleogel has a better potential for use as a fat substitute.

In order to study the structural properties and biological activities of the polysaccharides of Phlebopus portentosus, water-soluble polysaccharides from the fruiting body of P. portentosus were extracted by hot water extraction followed by ethanol precipitation, deproteinized using Sevag reagent, decolorized using macroporous adsorption resin, and purified to homogeneity by successive chromatography on DEAE-52 cellulose and Sephacryl S-400HR columns. The molecular mass of the purified polysaccharides was determined by high performance gel permeation chromatography (HPGPC), and the monosaccharide composition by high performance liquid chromatography (HPLC) following pre-column derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP). Ultraviolet (UV) absorption spectroscopy was used to examine whether the polysaccharide samples contained proteins or nucleic acids, and the types of functional groups, structure and morphology were characterized by infrared spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and scanning electron microscopy (SEM), respectively. The polysaccharide with high α-glucosidase inhibitory activity was selected to evaluate its inhibition kinetics on α-glucosidase. Furthermore, its in vitro hypoglycemic mechanism and inhibitory type were clarified. The results showed that among four macroporous resins (HP 2MGL, HP 20, SP 850 and SP 825) tested, SP 825 macroporous resin had the best decolorization efficiency. The fraction PPP-0 had a weight average molecular weight (mw) of 31 059 Da. Moreover, it was a heteropolysaccharide mainly composed of galactose, glucose, fucose and mannose that were linked by α- and β-glycosidic bonds. In vitro hypoglycemic experiments showed that the crude polysaccharide and the three purified polysaccharide fractions all exhibited inhibitory activity on α-glucosidase, among which PPP-2 had the highest inhibitory rate, followed by PPP-0. The inhibition was competitive and reversible. This study could provide a theoretical basis for the development of functional foods with hypoglycemic activity and hypoglycemic agents from P. portentosus polysaccharides.

To explore the effects of different curcumin concentrations on the gel properties of pork myofibrillar proteins (MPs), changes in gel whiteness, cooking loss, water retention capacity, texture, dynamic rheology, intermolecular forces, microstructure, and protein electropherograms were evaluated after being treated with different concentrations of curcumin (0, 5, 10, 15 and 20 μmol/L) in a simulated oxidative system with 5 mmol/L H2O2. The results indicated that the addition of curcumin benefited the formation of a more stable and compact protein gel network structure and alleviated gel softening, structure loosening, decreased water-holding capacity, increased cooking loss and other problems caused by oxidation. Additionally, the rheological characterization revealed that the addition of curcumin enhanced both storage modulus (G’) and loss modulus (G”) of MP gels under oxidative conditions, thereby promoting the formation of elastic gels with stable three-dimensional network structures and improving the gel characteristics of MPs. Moreover, higher curcumin concentration within a certain range was more beneficial for gel formation.

Mixtures of maltodextrin (MD), egg yolk protein (EYP), Manchurian walnut protein isolate (MWPI) and soybean protein isolate (SPI) in different proportions were used as wall materials to prepare Manchurian walnut oil microcapsules by spray drying. The micromorphology, thermal stability, storage stability and antioxidant stability of microcapsules were analyzed. The results showed that the encapsulation efficiency of microcapsules prepared with MWPI was 73.68%, with an intact and dense structure, indicating that Manchurian walnut oil was successfully encapsulated in and protected by the microcapsules. The microcapsule powder had good flowability and solubility. The MWPI microcapsules lost only 5.48% of its initial mass under programmed heating conditions (10 ℃/min, up to 150 ℃), which was much lower than that of SPI microcapsules (10.3%), thereby being more able to meet the requirements of most thermally processed products. Microencapsulation obviously slowed down the oxidation rate of Manchurian walnut oil and improved its storage stability. The antioxidant experiments demonstrated that microencapsulation could effectively improve the antioxidant stability of active ingredients in Manchurian walnut oil. Therefore, this study demonstrated MWPI to be an excellent microcapsule wall material by evaluating its performance, which will expand the range of selection of protein-based wall materials, and provide a new idea for the application of walnut protein isolate resources to improve the added value of Manchurian walnut.

This study aimed to isolate and select potential probiotic strains from the feces of healthy forest musk deer and to evaluate their in vitro probiotic characteristics. Twelve isolates were obtained and identified by cell morphology and bacterial 16S rDNA sequencing. Their survival under low pH and bile salt conditions, antagonistic activities against five pathogens (Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa PAO1, Salmonella enteritidis ATCC 13076 and Arcanobacterium pyogenes LSN3), auto-aggregation characteristics, hydrophobicity, antibiotic susceptibility and antibiotic resistance genotypes, and growth curves were evaluated. The results showed that five Lactiplantibacillus plantarum isolates and one Pediococcus acidilactici isolate survived at pH 4, or in 0.5% bile salt with survival rates of more than 88.5% and 87%, respectively. All of them inhibited the five pathogens with diameters of inhibition zones of 17.20-20.19 mm for E. coli ATCC 25922, S. aureus ATCC 25923, P. aeruginosa PAO1 and S. enteritidis ATCC 13076 and of 14.23-15.53 mm for A. pyogenes LSN3. They had similar auto-aggregation capacity (53.1%–56.2%) and surface hydrophobicity (52.9%–56.0%) to L. paracasei L22. They were resistant to streptomycin, ciprofloxacin and vancomycin, carried the vanX gene and rapidly grew; the optical density at 600 nm (OD600) reached 9.0 and 7.1 for L. plantarum and P. acidilactici from the gut of forest musk deer after 24 h incubation, respectively. Our findings demonstrated that these six isolates can be used as sources for the development of probiotic preparations intended for forest musk deer.

In this study, a strain, named S5-4, with high esterase activity was obtained from Nongxiangxing Daqu by primary and secondary screening, and subjected to whole genome sequencing, esterase annotation and metabolic pathway analysis. The strain exhibited a maximal ratio of transparent zone diameter to colony diameter (D/d) of 2.27 ± 0.02, and it was identified as Lactococcus garvieae. Its morphological, physiological, and biochemical characteristics were determined, and its esterase activity was measured to be 15.74 U/mL. This strain produced (0.345 0 ± 0.160 0) g/L of ethyl acetate and (0.298 3 ± 0.230 0) g/L of ethyl lactate after anaerobic fermentation at 35 ℃ for 15 days. The genome size of S5-4 was determined to be 2 191 113 bp in length, with a GC content of 37.99%. A total of 1 486 genes, including 4 rRNA genes, 69 tRNA genes, and 34 ncRNA genes were predicted. In total, 11 esterase genes were annotated in the genome of S5-4 including phosphatases (five intracellular ones and two membrane ones), acyl-CoA dehydrogenase (intracellular), triacylglycerol lipase (extracellular), carboxylase (extracellular), and hemicellulose esterase (intracellular). Based on functional genomic annotation, the metabolic pathways to produce ethyl acetate and ethyl lactate from starch and galactose as carbon sources were constructed and found to be consistent with the experimental results. Given its ability to produce esterase, the strain could be used as a biocatalyst for esterification in baijiu fermentation or as a flavor enhancer in Daqu production.

Objective: To study the preventive effects of Fructus Phyllanthiin (FP) alone and combined with tea polyphenols (FP-TP) or L-carnitine (FP-LC) on high-fat diet-induced obesity in rats. Methods: The experimental, model control and positive control groups were fed a high-fat diet while the negative control group was fed a normal diet. Meanwhile, the experimental group was gavaged with FP, FP-TP or FP-LC for seven weeks. At the end of the gavage period, body mass, perirenal fat mass and peritesticular fat mass were measured, and four items of blood lipid tests in serum and liver lipid levels were detected. The levels of serum leptin, resistin and lipocalin were measured, and the activities of related enzymes and total protein levels in the liver and mRNA expression in adipose tissues were measured to observe the effects of FP and its combination with TP or LC on obesity alleviation and protection against liver injury in experimentally obese rats. Results: The body mass and body fat content of the rats in the model control group increased significantly when compared with the negative control group (P < 0.001). The rats in the FP and FP-LC intervention groups showed significant decreases in body mass, and perirenal fat and peritesticular fat contents and indexes. The levels of total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) in the serum and liver decreased significantly, and the level of high-density lipoprotein cholesterol (HDL-C) increased significantly. Moreover, serum leptin and resistin levels significantly dropped, and lipocalin levels increased; the activities of alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and the content of malondialdehyde (MDA) in the liver decreased, and the activity of superoxide dismutase (SOD) increased; the mRNA expression of adenosine 5’-monophosphate-activated protein kinase (AMPK) α-2 was significantly up-regulated in adipose tissues. On the other hand, FP-TP intervention had no significant anti-obesity effect. Conclusion: FP can prevent high-fat diet-induced obesity in rats, being more effective when used alone than when combined with TP or LC.

Flammulina velutipes polysaccharides (FVP) have been reported to exhibit excellent anti-inflammatory and antioxidant effects. This study further investigated the efficacy and mechanism of action of FVP in alleviating vascular injury induced by benzo[a]pyrene (BaP) in mice. The expression of vascular inflammatory cytokines was assessed through immunohistochemistry analysis. Flow cytometry was used to analyze the proportion of pro-inflammatory cells in the peripheral blood and spleen as well as the composition of hematopoietic stem cell (HSC) subsets in bone marrow. The results demonstrated that FVP treatment mitigated the expression of vascular pro-inflammatory cytokines such as interleukin-6, monocyte chemoattractant protein-1 and intercellular cell adhesion molecule-1 in mice induced by BaP. Moreover, FVP treatment significantly inhibited the increases in the proportions of monocytes, macrophages and neutrophils in the peripheral blood and those of macrophages and neutrophils in the spleen of BaP-induced mice. Further analysis of bone marrow HSC subsets revealed that BaP exposure elevated the proportions of hematopoietic progenitor cells and granulocyte-macrophage progenitor cells in mouse bone marrow, while reducing the proportions of hematopoietic stem cells and common myeloid progenitor cells, which were reversed by FVP treatment, thus restoring bone marrow HSC subsets to the level of the healthy control group. At the cellular level, FVP suppressed BaP-induced oxidative stress in Raw264.7 cells. Taken together, FVP alleviate BaP-induced vascular inflammatory injury by maintaining the homeostasis of the bone marrow hematopoietic system, thereby regulating the output of pro-inflammatory cells into the circulatory system, and down-regulating the proportion of peripheral pro-inflammatory cells.

Objective: Metabolomics based on ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF-MS) was applied to explore the metabolic changes in the urine of mice with Alzheimer’s disease (AD) after intervention with camellia oil. Methods: Mice were randomly divided into four groups: normal control, AD model, positive drug and camellia oil treatment. In all mice except for those in the control group, AD was induced by amyloid β-protein (Aβ) 25-35 peptide, and urine samples were collected from each group for UPLC-Q/TOF-MS analysis after protein precipitation. The obtain urine metabolite data were analyzed by the SIMCA-P14.1 software with principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA). Using the online databases of HMBD, MassBank, MetaboAnalyst and Kyoto Encyclopedia of Genes and Genomes (KEGG), biomarker identification, pathway enrichment analysis, and metabolic network construction were conducted. Results: In the PCA score plots, the camellia oil group was clearly separated from the model group and closer to the normal group. Totally 48 biomarkers were identified and the major pathways involved were taurine and hypotaurine metabolism, arginine and proline metabolism, cysteine and methionine metabolism, alanine, aspartate and glutamate metabolism. Conclusion: Camellia oil can improve the metabolism of AD mice by regulating energy metabolism, amino acid metabolism and other pathways, which provides a reference for further study of camellia oil intervention against AD.

This study was performed in order to explore the correlation between the monosaccharide composition and hypoglycemic activity of Berberi dasystachya polysaccharides (BDPs). BDPs were extracted with hot water from B. dasystachya fruit from five regions of Qinghai province (I–V). The chemical compositions and primary structures of BDPs were determined, and their in vitro hypoglycemic activity was evaluated in terms of α-glucosidase and α-amylase inhibitory activities, and their protective effect against apoptosis induced by glucolipotoxicity (GLTy) in RIN-m5F cells was assessed. The results showed that BDPs were heteropolysaccharides connected by β-glycosidic bonds that had apyranose backbone without a triple-helix conformation, and exhibited excellent thermal stability at temperatures below 200 ℃. In addition, the monosaccharide composition and molecular mass of BDPs varied significantly depending on geographical origin. BDP-I showed good hypoglycemic activity in vitro, and the inhibitory rate of BDP-I on α-amylase was as high as 67.41% (P < 0.05). BDPs exhibited good protective effects on GLTY-induced apoptosis in RIN-m5F cells, and BDP-I had the best cell proliferation-promoting activity, which effectively decreased the levels of reactive oxygen species (ROS) and tumor necrosis factor-α (TNF-α). Finally, correlation analysis showed that monosaccharides such as glucose (Glc), galactose (Gal), rhamnose (Rha) exhibited a strongly positive correlation with hypoglycemic activity in vitro, and there was a strongly negative correlation between mannose (Man) and ROS levels. This study provides a theoretical basis for the utilization and development of B. dasystachya Maxim. berry in terms of hypoglycemic activity.

In order to investigate the material basis of the uric acid-lowering activity of Gynura procumbens, G. procumbens extracts obtained by hot reflux extraction with different ethanol concentrations (0%, 30% and 70%) were evaluated for bioactive ingredients, xanthine oxidase (XOD) inhibitory activity and antioxidant activity. The extracts were analyzed and identified by non-targeted metabolomics. Meanwhile, the 30% and 70% ethanol extracts, which exhibited high XOD inhibitory activity, was evaluated for uric acid-lowering activity in a mouse model of hyperuricemia induced by hypoxanthine and potassium oxonate. The results showed that the XOD inhibitory activity of the extracts was significantly positively correlated with the total flavonoid and total organic acid contents (P < 0.05 and P < 0.01, respectively), and the superoxide anion scavenging capacity was significantly positively correlated with the total phenol content (P < 0.01). A total of 705 differential metabolites were detected by non-targeted metabolomics. In vitro experiments revealed that naringenin, 1,5-dicaffeoylquinic acid, α-linolenic acid, ferulic acid and diosmetin were the key contributors to the uric acid-lowering activity of G. procumbens. Both 30% and 70% ethanol extracts alleviated hyperuricemia by lowering serum uric acid and inhibiting XOD (P < 0.01), and alleviated hyperuricemia-induced oxidative liver damage. In this study, through in vivo and in vitro experiments, the uric acid lowering activity of G. procumbens was verified, and the basis of the uric acid lowering substance was discussed, which could provide a theoretical basis for the preparation of uric acid-lowering substances from G. procumbens and the development of functional foods with uric acid-lowering activity.

This study investigated the mechanism by which A-type oligomeric proanthocyanidins (A-OPC) from abscising litchi fruits inhibit proinflammation induced by litchi thaumatin-like protein (LcTLP). A-OPC were prepared by sequential ethanol extraction and purification by macroporous adsorption resin and preparative liquid chromatography. Structural analysis showed that A-OPC were mainly composed of proanthocyanidin A2, two A-type proanthocyanidin trimers and one A-type tetramer, with a purity of 88.69%. At 120 μg/mL concentration, A-OPC inhibited the secretion of nitric oxide (NO), interleukin (IL)-6 and tumor necrosis factor-α (TNF-α) by 58.38%, 39.80% and 86.31% in RAW264.7 cells treated with LcTLP, respectively (P < 0.01). Western blot showed that 120 μg/mL A-OPC reduced the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and significantly decreased the phosphorylation levels of p65, inhibitor of NF-κB (IκBα), c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38. Therefore, A-OPC down-regulated the phosphorylation levels of downstream proteins in the nuclear transcription factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways, thereby suppressing LcTLP-induced inflammatory response.

In this study, the rheological and textural properties and water-holding capacity of pea 7S and 11S globulin gels induced by high hydrostatic pressure (HHP) at 100–500 MPa for 10 min were measured. The major interaction forces maintaining gel morphology were determined by dissolving the gels in different solvents. The microscopic structure of the gels was observed using scanning electron microscopy (SEM). The results showed that after HHP treatment at 300 MPa, pea 7S and 11S globulin solutions gradually turned into gels. When the pressure continued to increase to 500 MPa, the formed gels exhibited higher strength, harder texture and higher water-holding capacity. The 11S globulin had weaker gel-forming ability, but higher water-holding capacity (100%) compared with 7S. Furthermore, the overall water-holding capacity and gel strength of 7S–11S mixed gels (in mass ratios of 1:2, 1:1 and 2:1) were significantly improved compared with those of the neat gels. The major forces that maintain the gel structure were hydrogen bonds and hydrophobic interaction, followed by disulfide bonds and electrostatic interaction. Therefore, by changing HHP conditions, the strength and texture of pea globulin gels could be controlled.

Objective: Establish a computer model for predicting the inactivation of Zygosaccharomyces rouxii in apple juice by surface discharge plasma (SDP). Methods: The numerical simulation software COMSOL multiphysics was used to model SDP inactivation of Z. rouxii LB. The inactivation efficiency was evaluated under different conditions of discharge voltage, bubble size and sample volume. The model was then validated. Results: SDP was highly effective in deactivating hyperosmotic-resistant yeast in apple juice. The reaction rate coefficient decreased with an increase in the initial concentration of bacteria. Furthermore, the increase in discharge voltage shortened the time needed to inactivate yeasts. Bubble size variations had no significant effect on the inactivation of Z. rouxii LB, and the inactivation time was prolonged with increasing sample volume. The model simulation results agreed with the experimental data.

Objective: To investigate the effect of dielectric barrier discharge cold plasma (DBD) treatment on the cell wall metabolism and softening characteristics of Xiaobai apricot during storage. Methods: Xinjiang-grown Xiaobai apricot fruits were treated with DBD for 40 s (voltage of 90 kV), and stored at 4 ℃ and 95% relative humidity for up to 42 days. The contents of cell wall components, cell wall metabolic enzyme activities, and quality indicators of apricot fruits were measured every seven days. Results: DBD treatment improved the quality of apricot, reduced the contents of malondialdehyde (MDA) and hydrogen peroxide, and significantly inhibited cell wall-degrading enzymes. It also delayed the dissolution of pectin and the degradation of cellulose, and inhibited the migration and loss of water in apricot fruits. Transmission electron microscopy (TEM) showed that DBD treatment helped to maintain the cell wall structure, thus making it more uniform and complete. Conclusion: DBD treatment can effectively inhibit the activities of cell wall-degrading enzymes of apricot fruits during storage, thereby enhancing the cell wall structure and delaying fruit softening.

In order to determine the optimal method for drying Apostichopus japonicus gonads, the effects of four drying methods, namely, hot air drying, cold air drying, microwave drying and vacuum freezing drying, on the lipid composition, lipid stability and fatty acid nutritional value of A. japonicus gonads were analyzed and compared. The results showed that the contents of total lipids, phospholipids, triglycerides and astaxanthin reduced to different degrees after drying treatments. The peroxide value (POV) significantly reduced, and the thiobarbituric acid reactive substances (TBARS) value significantly increased (P < 0.05). In terms of fatty acid nutritional values, the atherogenic and thrombogenic indices decreased to different degrees after drying treatments, and the hypocholesterolemic/hypercholesterolemic indices increased significantly (P < 0.05). The results of electronic nose analysis showed significant differences in odor characteristics among dried samples obtained using different drying methods. Gas chromatography-ion mobility spectrometry (GC-IMS) identified 28 volatile substances from fresh and dried samples, among which, 2,5-dimethyl pyrazine was detected only in microwave-dried samples, while pentanal and ethyl acetate were odor-active substances unique to cold air-dried samples. In conclusion, vacuum freeze drying effectively slowed down the rate of lipid oxidation, but the samples were relatively bland in odor. Hot air, cold air and microwave drying all promoted lipid oxidation, but improved the nutritional value of fatty acids and enriched the odor characteristics of the samples. The results of this study could provide a theoretical basis for the processing and utilization of A. japonicus gonads.

The extraction efficiency, physicochemical properties, and structural characteristics of β-glucan extracted from highland barley branby sequential microwave-ultrasound-assisted extraction were explored. At the same heating rate, microwave enhanced α-amylase activity. The extraction efficiency of highland barley β-glucan was correlated with ultrasound power and treatment time. An ultrasound power of 600 W for 30 min and microwave heating at 60 ℃ for 30 min resulted in the maximum β-glucan yield of (6.30 ± 0.38)%. The results of physicochemical properties showed that with increasing sonication time up to 40 min, the solubility and foaming capacity of barley β-glucan increased significantly (P < 0.05), while the turbidity and emulsifying capacity decreased significantly (P < 0.05). The results of particle size distribution showed that with increasing sonication time, the relative molecular mass of barley β-glucan decreased, and ultrasound changed the rheological behavior of β-glucan, decreasingits viscosity and resulting in shear thinning. The infrared spectroscopic results showed that sonication did not change the functional groups of β-glucan, but it caused partial breakage of the glycosidic bonds. The microscopic results showed that ultrasonic treatment led to a looser structure of barley β-glucan, which was conducive to improving its extraction efficiency. Therefore, the microwave-ultrasound-assisted extraction of β-glucan from highland barley provides a basis for developing new food types and functional products.

In this study, a mixture of ultrasound or microwave pretreated walnut meal protein peptides and CaCl2 was used for the preparation of walnut peptide-calcium chelate. The effects of different pretreatments on the calcium chelating capacity, structural changes and stability of walnut meal protein peptides were analyzed. The results showed that compared with walnut meal protein peptide-calcium chelate (WPP-Ca), the chelation rates of ultrasound-pretreated walnut meal protein peptide-calcium chelate (UP-WPP-Ca) and microwave-pretreated walnut meal protein peptide-calcium chelate (MP-WPP-Ca) were enhanced, which indicated that ultrasound and microwave pretreatments improved the calcium-chelating capacity of the peptides effectively. Using ultraviolet-visible (UV-Vis) absorption spectroscopy and Fourier transform infrared (FTIR) spectroscopy, it was found that ultrasound and microwave pretreatments mainly affected the calcium ion binding sites such as amino groups, carbonyl groups, carboxyl groups, amide bonds and carboxylate groups of walnut meal protein peptides. The results of X-ray diffraction (XRD) showed that ultrasound and microwave treatments changed the molecular arrangement of walnut meal protein peptides, thereby making the structure of walnut peptide-calcium chelate more ordered. Fluorescence spectroscopy showed that ultrasonic and microwave treatments promoted the chelation between aromatic amino acids and calcium ions. In addition, UP-WPP-Ca and MP-WPP-Ca showed good stability toward different pH values, temperatures, and gastrointestinal digestion. In short, ultrasonic and microwave pretreatments can improve the calcium-chelating capacity and stability of walnut meal protein peptides, which is of guiding significance for the processing of walnut peptide-calcium chelate and the development of calcium supplements.

In order to elucidate the relationship between the oxidative phosphorylation and the color stability of Tan sheep meat during postmortem storage, the changes in the color stability and oxidative phosphorylation of the Longissimus dorsi of 6-month-old Tan sheep were determined after 0, 1, 2, 3, 4, 6 and 8 days of postmortem storage at 4 ℃. The results showed that L*, a* and b* values increased first and then decreased during 0–8 days of storage (P < 0.05), and so did R630/R580 ratio (P < 0.05). The relative content of metmyoglobin (MetMb) showed a decreasing and then increasing trend (P < 0.05), whereas the relative content of oxymyoglobin (OxyMb) exhibited the opposite trend (P < 0.05), and the relative content of deoxymyoglobin (DeoMb) showed a decreasing trend (P < 0.05). Mitochondrial membrane permeability significantly increased (P < 0.05), and mitochondrial membrane potential significantly decreased (P < 0.05). The activity of mitochondrial complex I, II, III and IV significantly decreased (P < 0.05), while the activity of complex V significantly increased (P < 0.05). Reactive oxygen species (ROS) levels significantly increased (P < 0.05). The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) significantly decreased (P < 0.05). Catalase (CAT) activity first increased and then decreased (P < 0.05). The contents of ATP, ADP and AMP significantly decreased (P < 0.05). The relative contents of MetMb, OxyMb and DeoMb and meat color parameters were significantly correlated with oxidative phosphorylation. The above results indicate that the failure of endogenous antioxidant enzymes in Tan sheep meat during postmortem storage led to excessive ROS production in myocytes, which damaged the integrity of mitochondria, and then affected the activities of enzymes related to mitochondrial oxidative phosphorylation and consequently the activity of MetMb reductase in myocytes, which resulted in the failure of MetMb reduction, thereby leading to deterioration of the color stability of Tan sheep meat.

To investigate the effects of different moisture contents on the storability of lightly salted large yellow croaker at 4 ℃, changes in total volatile basic nitrogen (TVB-N) content, microbial community composition, taste and volatile organic compounds were analyzed during the storage period, and the correlation between microbial community composition and VOCs was examined. The results showed that the shelf-life of lightly salted large yellow croaker with moisture contents of 60%, 55%, and 50% was 27, 33, and 39 days, respectively. During storage, there were significant changes in the bacterial flora, with four specific spoilage organisms (SSOs) being dominant at the end of the shelf-life. In the samples with 60% moisture content, Hafnia alvei (61.22%) and Brochothrix thermosphacta (19.39%) were dominant. In the samples with 55% moisture content, H. alvei (31.13%), B. thermosphacta (29.25%), Carnobacterium divergens (17.92%) and Citrobacter freundii (16.98%) were dominant. C. freundii was not observed at the end of the shelf-life of lightly salted large yellow croaker with 50% moisture content, and H. alvei (43.96%) and B. thermosphacta (37.36%) were dominant, respectively.The electronic tongue results showed that the trend of response values was basically the same among the three groups of samples. A total of 29 VOCs were detected by gas chromatography-ion mobility spectrometry (GC-IMS), including seven alcohols, six esters, four ketones, four aldehydes, three amines, two heterocycles, one olefin, one ether and one terpene. The fingerprinting results showed no significant difference in the composition of VOCs among the groups. Pearson’s correlation analysis showed that H. alvei and B. thermosphacta were positively correlated with amines for all groups.

We investigated the effect and underlying mechanism of postharvest treatment with 0.5 mmol/L melatonin (MT) treatment 1 h on chilling injury (CI) and ripening of ‘Guifei’ mango fruits during 4 days of shelf life at 25 ℃ after refrigeration at 4 ℃ for 28 days. The results showed that MT treatment markedly decreased CI and enhanced soluble solids content (SSC), respiration rate and ethylene production, while accelerating the decline in hue value and firmness of chilled mango fruits. Compared with the control group, MT treatment promoted the increase in the contents of water-soluble pectin (WSP) and chelate-soluble pectin (CSP) and the activities of polygalacturonase, β-galactosidase and endo-1,4-β-D-glucanase and accelerated the decrease in pectin methylesterase activity, thereby leading to cell wall degradation and fruit softening. Compared with the control group, higher activities of 1-aminocyclopropane-1-carboxylic acid synthase (ACS) and 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) and the expressions of their encoding genes (MiACS and MiACO) were observed in MT-treated fruits. Moreover, MT up-regulated the expression of MiETR1, MiERS1, MiERF1, MiEIN2, MiCBF1 and MiICE1 while down-regulating the expression of MiCTR1. These results indicated that MT treatment could promote the restoration of ripening and reduce CI in mango fruits during shelf life after storage at low temperature.

To investigate the effects of different irradiation treatments on the quality of black pepper beef during storage, a backpropagation-artificial neural network (BP-ANN) model for predicting various quality attributes of black pepper beef was developed based on physicochemical indicators. Irradiation at a dose of 3–4 kGy effectively delayed the loss of juice, lipid oxidation, and protein degradation in black pepper beef during storage, maintained its hardness and microstructure, and increased the contents of umami (Asp) and sweet (Gly, Ala and Ser) amino acids. The BP-ANN model was optimized with the juice loss, thiobarbituric acid reactive substances (TBARs) value, total volatile basic nitrogen (TVB-N) content, tropomyosin band intensity ratio, myosin heavy chain band intensity ratio, and total free amino acid content of irradiated black pepper beef as input variables. The ReLU function was used as the activation function, with 14 neurons in the hidden layer and 100 iterations. The results showed that the 6-14-6 BP-ANN model could predict the quality changes of irradiated black pepper beef well, and have great potential in predicting various qualities of irradiated meat products.

Air-packaged and nitrogen-packaged Pelteobagrus fulvidraco were evaluated for changes in freshness indices, microbial flora and volatile flavor substances during cold storage at 4 ℃. The results showed that nitrogen gas packaging slowed down the growth rate of total bacterial count (TBC), total volatile basic nitrogen (TVB-N) value and pH, effectively maintained the color, hardness and sensory quality, and prolonged the shelf-life of P. fulvidraco by two days. Nitrogen gas packaging affected the changes in the microfloral structure of P. fulvidraco during cold storage, and prevented Pseudomonas from becoming the dominant spoilage bacteria. Notably, it had a significant inhibitory effect on Acinetobacter on the 3rd day of cold storage (P < 0.01). Compared with the non-nitrogen group, nitrogen gas packaging reduced the types and contents of alcohols, aldehydes, ketones and esters in P. fulvidraco during the refrigeration process. The results of redundancy analysis (RDA) performed on microbial communities and volatile flavor substances showed that Pseudomonas aeruginosa and Bacillus immobilis played an important role in the flavor changes, and were positively correlated with the production of spoilage markers such as n-octanal, 3-hydroxy-2-butanone, 3-methylbutanol and 1-octanol. Therefore, nitrogen gas packaging could slow down the growth of dominant spoilage bacteria for a short period, thus delaying the deterioration of the freshness and flavor of P. fulvidraco, which could be a simple and effective method to prolong the shelf-life of P. fulvidraco.

In this study, the optimal concentrations of methyl jasmonate (MeJA) and methyl dihydrojasmonate (MDJA) for Cabernet Gernischt were selected based on basic physicochemical properties of grapes. The key volatile metabolites and key enzyme activities in response to MeJA and MDJA were analyzed by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and enzyme-linked immunosorbent assay (ELISA), respectively. The effects of pre-harvest MeJA or MDJA treatment on the fruit quality and green leaf volatile components in the lipoxygenase (LOX) metabolic pathway of Cabernet Gernischt were also investigated. The findings revealed that the application of 0.1 mmol/L MeJA or 5 mmol/L MDJA significantly enhanced mass of 100 berries, total sugar content, soluble solids content, pH, total phenol and total anthocyanin contents. Compared with the control group, MeJA increased these indexes by 10.24%, 27.83%, 28.24%, 4.80%, 77.63% and 85.29%, respectively, while MDJA increased them by 9.15%, 24.01%, 24.41%, 8.30%, 69.21% and 71.57%, respectively. Furthermore, MeJA and MDJA reduced titratable acid content by 40.0% and 30.24%, respectively. Accordingly, both MeJA and MDJA significantly improved fruit quality. Moreover, they significantly increased the contents of C6 compounds responsible for the typical aroma of Cabernet Gernischet. Significant correlations were observed between the activity of each key enzyme in the lipoxygenase metabolic pathway and the corresponding metabolites, indicating that the application of MeJA or MDJA at a suitable concentration could positively influence the accumulation of green leaf volatiles in Cabernet Gernischt.

In this study, we established a method for the determination of three metabolic regulators including clomiphene, trimetazidine and meldonium in foods by pass-through solid phase extraction combined with ultra-high performance liquid chromatography-tandem mass spectrometry (SPE-UPLC-MS/MS). The samples were extracted with 5% formic acid in acetonitrile, and the extract was purified on a pass-through solid phase extraction column and chromatographically separated on an amide column (3.0 mm × 100 mm, 1.7 μm). The separated analytes were detected in the multiple reaction monitoring (MRM) mode, and quantitated by an internal standard method. Good linearity was observed for clomiphene and trimetazidine within the concentration range of 1.0-40.0 ng/mL, and 5.0-200.0 ng/mL for meldonium. The average recoveries for spiked samples ranged from 81.3% to 100.7%, and the relative standard deviations (RSD) were between 0.3% and 6.1% (n = 6). The developed method was simple, rapid and practical with low matrix interferences, and was generally suitable for the determination of clomiphene, trimetazidine and meldonium in foods, which could provide effective technical support for the assurance of food safety for sports events.

A method for the quantification of 1,3-dioleyl-2-palmitoyl-glycerol (OPO) in infant formula was developed. The samples were treated with ammonia and extracted with organic solvents. The fat containing OPO was purified on a NH2 solid-phase extraction (SPE) cartridge packed with aminopropyl as the sorbent. The eluate was separated by silver ion chromatography using 0.55% acetonitrile-hexane as the mobile phase. The detection was carried out with a high performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD). This novel procedure enabled the complete separation of OPO and its isomer 1,2-dioleyl-3-palmitoyl-glycerol (OOP), thus allowing for the accurate quantification of OPO. The developed method showed the desired linearity in the concentration range of 25–500 μg/mL with a determination coefficient (R2) of 0.999 6. The limits of detection (LOD) and limits of quantification (LOQ) were 0.30 and 0.90 g/kg, respectively. At spiked concentrations from 1 to 96 g/kg, the average recoveries of OPO varied from 97.1% to 104.2% with relative standard deviations (RSD) between 1.2% and 2.9%. The precision and accuracy of this method met the relevant requirements, and it passed the inter-laboratory collaborative validation. Our investigation analyzed 39 commercial samples of OPO-fortified infant formula in China, revealing that the measured OPO content only accounted for 28.4% to 59.7% of the labelled value, which is mainly due to the inconsistency of detection methods.

To improve the effectiveness of dairy product safety governance, it is necessary to explore the development and mechanism of dairy product safety governance in China from a policy perspective. The texts of policies concerning dairy products from 2002 to 2021 were quantified by the grounded theory to form a dairy product safety assurance system including governance elements and behaviors. Then, based on the quantitative results and social network analysis, the evolutionary process and mechanism of dairy product safety governancein China were dissected. It was found that China’s dairy safety governance has gone through an evolutionary process from mandatory government supervision, emergency governance, government-led and enterprise-assisted governance to social co-governance. The whole evolution process reflects the country’s focus on the governance behaviors and modes, and reveals the mechanism of the comprehensive governance of dairy product safety. The governance actors work together on the governance elements through the interactions of the governance behaviors, and the governance role is reflected in the safety of dairy products through the governance elements, thus guaranteeing the quality and safety of dairy products.

Thawing is an important unit operation in the processing of frozen meat. Some of the major concerns for its application are thawing duration, temperature uniformity, juice loss, cooking loss, freshness, texture characteristics and taste changes. Good thawing quality for frozen meat can be obtained by choosing appropriate thawing technologies and processing parameters. The traditional thawing technologies include air thawing and water immersion thawing, while several novel physical field thawing methods have been developed include microwave thawing, radio-frequency thawing, infrared thawing and ohmic thawing. The microwave and radio-frequency methods, which both utilize high-frequency electromagnetic wave as excitation source, have seen increasing application in the field of frozen meat processing because of short operating time and high efficiency. This article reviews dielectric thawing technology, summarizes its key influential factors, discusses the changes in meat quality during the dielectric thawing process, and puts forward some thoughts regarding the common problems and future research directions in dielectric thawing.

Breast milk is the safest and most perfect natural food for infant growth and development. As one of the most important components in breast milk, the milk fat globule membrane (MFGM) is a 3-layer membrane structure surrounding milk fat globules (MFG). This unique structure not only maintains the stability of milk but also plays an important role in the digestive and metabolic processes of infants. In this article, we introduce the reader to the composition and structural specificity of MFGM, review the sequential digestion of MFGM depending on several enzymes in the mouth, stomach and intestine of healthy infants, and elaborate on the interaction mechanism between MFGM and various enzymes, in order to provide a reference for relevant studies.

Phospholipids, a class of polar lipids with complex structure and multiple functions, are composed of glycerophospholipids and sphingomyelins. As an important component of cell membranes, phospholipids are involved in many physiological activities, such as cell signal transduction, lipid droplet formation and cell apoptosis. The transformation, hydrolysis and oxidation of phospholipids impart meat and meat products with unique texture, flavor and nutritional quality. The functional properties of phospholipids vary with their polar groups and the type of fatty acids at the sn-1/sn-2 positions, and lipidomics provides powerful technical support for the structural confirmation and characterization of phospholipids. In this article, the structures and functions of phospholipids and the methods for their detection and analysis are reviewed with a focus on recent progress in research on how phospholipids are involved in intramuscular fat deposition in farm animals and regulate the quality of fresh meat and processed meat products, in order to provide references for precise regulation of the quality of livestock and poultry meat.

Steamed bread is one of the traditional Chinese staple foods, with a history of over 1 700 years. With the continuous improvement of people’s quality of life, a more abundant variety of steamed bread has been made, and the demand for flavor has become more and more important. Consumers are attracted by steamed bread with pleasant flavor, so there are higher requirements for industrial yeast fermented steamed bread. There are many factors that influence the flavor formation of steamed bread, including the type of leavening agent, raw materials and processing technology. Different starters significantly affect the flavor formation of steamed bread due to the different types and numbers of microorganisms they contain. The major factors affecting the flavor of steamed bread are reviewed to provide a reference for theoretical studies of steamed bread flavor and provide practical guidance for the development of steamed bread with better flavor suitable for industrial production.

During the freezing, storage, and thawing process, physicochemical changes occur in raw meat, which will inevitably lead to quality deterioration mainly including decreased water-holding capacity and the deterioration of color and texture. The quality deterioration can be effectively reduced by novel freezing and its assistive technologies. This article summarizes the quality deterioration mechanism of raw meat during freezing and frozen storage, and reviews the approaches for improving frozen meat quality, such as novel freezing techniques, cryoprotectants, novel packaging techniques and novel thawing techniques, which will provide a theoretical basis and technical guidance for improving the quality of frozen meat.

Mutton is a high-quality meat with high nutritional value. However, the typical species-specific flavor (odor) of mutton affects its quality and limits its consumer acceptance. Studies have shown that the major substances that cause mutton odor are 4-alkyl branched fatty acids, 3-methylindole, 4-methylphenol, stearic acids, and amino acids. The composition and formation pathway of mutton odor substances are complex and influenced by various factors such as nutrition, feeding system, variety, sex, age, and tissue position, so it is difficult to reduce mutton odor. Therefore, this article reviews the sources and formation mechanisms of mutton odor substances, the factors affecting the formation of mutton odor substances, and deodorization methods, which will provide a basis for scientifically regulating the flavor of mutton and its products.

Postharvest preservation of edible fungi is crucial for promoting the healthy development of the edible fungi industry. To systematically review the development history of research on postharvest preservation of edible fungi and to predict future trends, this paper used bibliometric methods to analyzes 421 pieces of relevant literature published in the Web of Science database between 2000 and the first three quarter of 2022 in terms of literature publishing, research collaboration, key authors, important literature, literature citations, and keywords. CiteSpace software was used for visual analysis. The results indicated that the amount and citations of literature on the preservation of edible fungi had steadily increased since 2000, with a trend of rapid growth since 2015 until the third quarter of 2022. Chinese research institutions and authors had significant impact in this field, who had participated in international collaboration most extensively and produced the most research achievements. The analysis of literature citations and keywords revealed that the frontier hotspots in this field were cell wall metabolism, energy metabolism, and active packaging research. The direction of energy metabolism was particularly noteworthy. Maintaining normal cell energy metabolism and antioxidant activity is essential for edible fungi to resist postharvest deterioration. Therefore, exploring new preservation technologies and elucidating their molecular mechanisms will be an important research direction in the future.

Postbiotics are inanimate microbial cells and/or their components as well as microecological preparations made from their metabolites, which are beneficial to the health of the host. Postbiotics can regulate intestinal microbial balance, enhance immunity, and have anti-inflammatory and antibacterial effects. Compared with probiotics, living bacterial cells, postbiotics are safer, and more stable, effective and convenient. This article summarizes the origin, microbial sources, preparation methods and advantages of postbiotics, and elucidates the mechanisms of action of postbiotics in comparison with those of probiotics. In addition, it introduces readers to the applications of postbiotics as functional food supplements, food quality improvers, food preservatives and detoxifying agents in foods. We believe that as the definition, classification, and functional components of postbiotics become clearer, they will be more widely used in the fields of foods, nutraceuticals, foods for special medical purpose, infant foods, and personal care products. The development of postbiotics will also promote the leapfrog development of basic and applied science.