Ɛ -Poly-L-lysine ( Ɛ -PL), a natural and broad-spectrum preservative, is extensively utilized in food, cosmetic and pharmaceutical industries.Currently, Ɛ -PL is mainly produced through submerged fermentation by Streptomyces albulus.The carbon source glucose generally accounts for most of the Ɛ -PL production costs.Therefore, developing cheaper and alternative carbon sources is crucial for Ɛ -PL fermentation.In this study, sweet potato residue hydrolysate (SPRH) used as carbon sources for Ɛ -PL production by S. albulus ZY1 was investigated.When the initial glucose concentration in the SPRH was 50 g/L, after 72 h of shake flask fermentation, the Ɛ -PL titer achieved 1.55 g/L.In addition, compared with the M3G medium (a conventional control medium using pure glucose as the sole carbon source), the activities of glucose-6-phosphate dehydrogenase and Ɛ -PL synthetase in the SPRH increased by 14.3% and 6.4% at 48 h, respectively.Subsequently, transcriptome analysis showed that 37 upregulated genes and 76 downregulated genes were identified.Among these, the ffs gene, which is involved in the protein translocation process mediated by the signal recognition particle (SRP), was upregulated.Finally, in fed-batch fermentation with a 5 L bioreactor, Ɛ -PL titer reached 39.09 g/L with a productivity of 4.89 g/(L·d) at the end of fermentation.In summary, this study provided a reference for efficient Ɛ -PL production using agricultural residues as economical carbon sources.

Fructooligosaccharide (FOS), as an important prebiotic, is experiencing continuously growing market demand, and there is a pressing need for the development of an efficient and low-cost production process.This study aims to mine novel endo-inulinase genes from microorganisms to achieve high-yield production of FOS.Five uncharacterized endo-inulinase genes were selected through gene mining, followed by cloning and recombinant expression using an E.coli expression system, after which their enzymatic properties were determined.The results indicated that the recombinant endo-inulinase from Emericella rugulosa (ER-INU1) exhibited a significantly higher catalytic efficiency than the other four enzymes.ER-INU1 exhibited an optimal temperature range of 50-55 ℃ and an optimal pH range of 5.0-6.0.Moreover, it retained over 85% of its initial activity after 4 hours of incubation at 50 ℃.Furthermore, using inulin as the substrate, the enzymatic hydrolysis conditions for ER-INU1 were optimized.The optimal reaction conditions for FOS production were determined as follows:pH 5.5, temperature 50 ℃, substrate concentration 40 g/L, and enzyme dosage 40 U/g.Under these conditions, after 4 hours of reaction, ER-INU1 was able to efficiently catalyze the hydrolysis of inulin, producing FOS with a degree of polymerization ranging from 3 to 6 and achieving a yield as high as 95%.The enzyme demonstrated significant advantages in both catalytic efficiency and product specificity, showing promising potential for industrial applications.It provides an efficient enzymatic resource for the large-scale production of functional FOS.

Trichoderma reesei possesses a strong capacity to synthesize and secrete a complete cellulase system.Through the determination of key biochemical indicators during the fermentation cycle, coupled with transcriptome sequencing, this study analyzed the differential gene expression profiles at the critical cellulase-producing stage (72 h) and the stage characterized by a marked decline in enzyme production efficiency (144 h).Results indicated that cellulase synthesis efficiency increased initially and then decreased.The efficiency at 144 h was significantly lower than that at 72 h.Concurrently, the fermentation broth viscosity increased, protein concentration decreased, and oxidative damage became more severe.Transcriptome analysis identified 2 773 differentially expressed genes (DEGs), comprising 1 554 downregulated and 1 219 upregulated genes.The expression of cellulase-encoding genes and regulatory factor xyr1 decreased significantly.Further analysis revealed that the downregulated genes were primarily enriched in pathways related to cellulase synthesis, carbon metabolism, and protein synthesis.The upregulated genes were mostly associated with oxidative stress responses.This study elucidates the mechanism of the decreased cellulase synthesis efficiency in Trichoderma reesei Ex-26 during the later fermentation stage.The findings provide a theoretical basis for optimizing fermentation processes and developing high-yield cellulase strains.

Diarrhea remains a serious threat to human health, and the development of safe and effective microecological preparations is an important alternative to antibiotic therapy.A laboratory-preserved strain of Pediococcus acidilactici served as the parental strain for atmospheric and room temperature plasma mutagenesis.A mutant with significantly enhanced antibacterial activity was screened and then evaluated for acid tolerance, bile salt tolerance, survival under simulated gastrointestinal conditions, auto-aggregation, cell surface hydrophobicity, and safety.Genome resequencing was further conducted to identify key mutant genes associated with the improved antibacterial activity.The antibacterial activity of the mutant increased by 22.85% compared with that of the parental strain.The survival rates were 62.99% at pH 3.0 and 73.80% in 0.3% bile salts.Auto-aggregation and cell surface hydrophobicity reached 77.83% and 58.19%, respectively.The survival rates in simulated gastric fluid and simulated intestinal fluid were 60.58% and 55.57%, respectively.The mutant also showed a high level of safety.Genome resequencing identified three categories of differential genes related to the enhanced antibacterial activity.In conclusion, a Pediococcus acidilactici mutant with high antibacterial activity was successfully obtained by ARTP mutagenesis.This study provides a promising strain resource and a theoretical basis for the development of novel microecological preparations for the prevention and treatment of diarrhea.

Traditional fermented dairy products are important sources of lactic acid bacteria (LAB).To screen LAB with probiotic potential from the Qinghai-Tibet Plateau, 101 candidate strains were isolated from traditional fermented yak milk in Xinjiang and Tibet.Strain characteristics were systematically evaluated, including acid tolerance, bile salt tolerance, simulated gastrointestinal fluid tolerance, auto-aggregation, surface hydrophobicity, and antioxidant activity.Safety testing and whole-genome sequencing (WGS) were also conducted on the screened strains.The results showed that the strain CD12-1 exhibited the best overall performance, with acid and bile salt tolerance rates of 73.34% and 37.43%, respectively.Survival rates in simulated gastric and intestinal fluids were 121.63% and 76.57%.Auto-aggregation and surface hydrophobicity reached 91.19% and 82.97%, and DPPH radical scavenging activity was 72.17%.The strain was sensitive to antibiotics such as erythromycin, penicillin, and cefazolin, and showed no hemolytic activity.Based on 16S rRNA gene sequence analysis, this strain was identified as Lacticaseibacillus paracasei.Whole-genome sequencing results revealed that its genome length was 2 483 754 bp with a GC content of 46.5%, containing 2 844 protein-coding genes.Functional annotation indicated that the strain’s genome was rich in genes related to acid resistance, adhesion, transport, bacteriocins, and cold/heat shock proteins, and no risk genetic elements with horizontal transfer potential were detected.In conclusion, CD12-1 shows strong probiotic potential and high safety, and its genomic features support its potential application use as a probiotic.

1,6-Hexanediamine is an important monomer for polyamide materials such as nylon 66, and the development of a biosynthetic route that is independently controllable, mild, and sustainable is of great significance.In this study, a cell-free catalytic system composed of carboxylic acid reductase and transaminase was constructed to improve the efficiency of 1,6-hexanediamine production from adipic acid.The efficiency of cascade flux transfer was enhanced through screening of key enzyme combinations and process intensification.The results showed that the titer of 1,6-hexanediamine reached 36.5 mg/L in the purified enzyme catalytic system.After the introduction of the cell-free catalytic system, the kinetic matching of the cascade reaction was improved and intermediate accumulation was alleviated, resulting in an increase in the titer of 1,6-hexanediamine to 329.7 mg/L.After further optimization of the reaction process, the maximum titer of 1,6-hexanediamine reached 571.8 mg/L at 9 h.These results lay a foundation for the green biomanufacturing of 1,6-hexanediamine and the process intensification of cell-free systems, and provide technical support for the further development of related biomanufacturing processes.

5-Hydroxyvaleric acid is a bio-based platform compound for the synthesis of δ-valerolactone and high-performance biodegradable polymers, and is of significant importance in the fields of green chemistry and novel materials.Constructing a genetically stable and high-yield strain is essential for the efficient biosynthesis of 5-hydroxyvalerate.In this study, a recombinant strain, DX-JN, was constructed using high-throughput screening markers, and the relationship between 5-hydroxyvaleric acid production and fluorescence intensity was established.Engineered strains producing 5-hydroxyvaleric acid were screened based on fluorescence intensity through a combination of ultraviolet (UV) mutagenesis and flow cytometry.Using this method, a high-yield 5-hydroxyvaleric acid-producing Escherichia coli strain, DXMCJN6-1, was obtained.A final yield of 15.99 g/L of 5-hydroxyvaleric acid was achieved when 30 g/L of glucose was consumed, corresponding to a glucose conversion rate of 53.3%.In contrast, the control strain DX-JN synthesized 8.71 g/L 5-hydroxyvaleric acid with a glucose conversion rate of 29%.Notably, the 5-hydroxyvaleric acid yield was significantly increased following high-throughput screening.Overall, both acid production and fermentation performance of the strain were enhanced through high-throughput strain breeding.

Raw milk is prone to quality deterioration during cold storage due to the proteolytic activity of psychrotrophic spoilage bacteria, particularly those belonging to the genus Pseudomonas.This study was conducted to clarify the proteolytic phenotypic characteristics of raw milk-derived Pseudomonas and to evaluate the applicability of different molecular typing methods in the consistency analysis of their spoilage phenotype clustering.A total of 31 Pseudomonas strains (including 26 isolates from raw milk in Shanghai and 5 type strains) were used as research subjects, and molecular typing was performed based on 16S rRNA gene sequences, ribotyping fingerprints, and a combination of housekeeping genes and protease genes using multi-locus sequence typing-like typing (MLST-like), respectively, to systematically compare the consistency of each typing result with the distribution of proteolytic phenotypes.The results showed that 67.7% of the strains produced clear zones on skim milk agar plates, and the average protease activity of the proteolytic-positive strains was 0.56 ΔA·h^-1·mL^-1.In species-level identification, ribotyping exhibited higher discriminatory power than 16S rRNA gene sequencing, with 48.4% of the strains identified as Pseudomonas fluorescens.The proteolytic capacity of the P. fluorescens group was significantly higher than that of the non-P. fluorescens group (P<0.000 1).Regarding consistency with the distribution of proteolytic spoilage phenotypes, the clustering results of 16S rRNA gene sequence analysis and ribotyping showed similar overall trends in the distribution of proteolytic phenotypes, while MLST-like typing exhibited the clearest correspondence with proteolytic capacity and the risk classification of proteolytic spoilage.This study revealed the distribution characteristics of proteolytic phenotypes of Pseudomonas in raw milk and evaluated the applicability of the three typing methods for identifying spoilage risk.These findings provided a reference for the identification and graded control of spoilage risk posed by Pseudomonas in raw milk.

As public attention to health continues to grow, functional food ingredients (e.g., bioactive lipids, carotenoids) have received increasing attention, leading to rising market demand.Conventional production methods such as plant extraction and chemical synthesis face inherent limitations.Microbial fermentation offers a sustainable alternative but encounters technical barriers, including low productivity, poor product stability, and high downstream costs.Lipid droplet engineering provides a promising strategy to overcome these challenges.This review summarizes recent advances in transforming lipid droplets from static storage units into dynamic functional hubs.It systematically discusses lipid droplet engineering strategies for improving product storage, stability, bioavailability, and secretion.This paper highlights key technologies, such as in situ biosynthesis via cellular compartmentalization, enhanced product stability through structural protein engineering, and optimized product release by regulating degradation pathways.The review also outlines enabling technologies such as multi-omics analyses and synthetic biology tools.In conclusion, this work provides a theoretical reference for the efficient biosynthesis of functional food ingredients through lipid droplet engineering.

This study aimed to screen high-yield protease-producing strains from marine symbiotic microbiota to provide microbial resources for developing novel protease preparations.Using the intestinal contents of marine tilapia as materials, a strain LfF-1 with high yield of metalloproteinase was isolated through plate screening and secondary fermentation-based activity assessment.The strain was identified as Bacillus velezensis via morphological observation, metabolic fingerprint analysis, and phylogenetic tree construction using concatenated sequences of the 16S rRNA and gyrB gene.The protease produced by this strain exhibits excellent characteristics:it is halotolerant (retaining 81.46% relative enzyme activity in 100 g/L NaCl), alkaliphilic (with an optimal pH around 11.0), and cold-adapted (maintaining 82.12% relative enzyme activity at 25 ℃).The fermentation medium for protease production was optimized through single-factor experiments and response surface methodology (RSM).The optimal medium composition was determined as follows:lactose (34.36 g/L), beef extract (18.54 g/L), KH₂PO₄ (5.40 g/L), wheat bran (33.20 g/L), with an initial pH of 7.0-7.5.The study also found that the suitable temperature for enzyme production of this strain was in the range of 27-33 ℃, and higher than 36 ℃ would significantly inhibit protease synthesis.Temperature-shift control (33 ℃ for 0-24 h;27 ℃ after 24 h) can effectively coordinate the growth of bacteria and enzyme production, and significantly improve the enzyme activity of fermentation broth.Notably, excess Mn²⁺, Zn²⁺, or Fe³⁺ in the culture medium can lead to the denaturation and inactivation of its protease, thus significantly reducing the enzyme activity of fermentation broth.In 5 L fermenter trials, using the optimized medium with temperature-shift control and fed-batch operation, the fermentation cycle was shortened to 60 h, achieving a maximum protease activity of 11 500 U/mL and increasing total protease yield by 76.9% compared to batch fermentation, showing significant advantages over the reported enzyme production levels of similar strains.The results showed that B.velezensis LfF-1 possesses high protease-producing capacity, and the produced protease has outstanding adaptability to extreme environments.The optimized fermentation process prozides technical support for its industrial application.

The material-to-water ratio (MWR) is one of the key parameters affecting the quality of semi-solid fermentation Baijiu.However, the effects of material-to-water ratio on the formation of its quality remain unclear.To clarify these effects, fermentation was carried out using a process involving solid-state saccharification followed by liquid-state fermentation at four MWRs (2∶1, 2∶2, 2∶3, and 2∶4, g∶mL). Dynamic changes in temperature, pH, reducing sugar, ethanol contents and so on were monitored, and volatile flavor compounds were analyzed by GC-MS to systematically investigate the effect of MWR on the fermentation process of Baijiu.The results showed that all fermentation groups exhibited typical kinetic patterns, and the MWR had a significant effect on fermentation rate and metabolic efficiency (P<0.05).Compared with the high-MWR group (2∶1), the low-MWR group (2∶4) showed a lower overall temperature and smaller thermal fluctuations, indicating greater thermal stability.In the early fermentation stage (d0-d3), the temperature rise rate of the 2∶1 group was 1.35 times that of the 2∶4 group.During fermentation, the pH in all groups followed a “decrease-increase” trend, and the low-MWR group maintained a lower pH.At the mid-fermentation stage (d3), pH was significantly and negatively correlated with system moisture content (R²=0.99);a 10% increase in water content led to an average pH decrease of about 0.11, indicating stronger acidification under higher moisture conditions.Dynamic changes in reducing sugar and ethanol showed that in the early fermentation stage (d1-d2), the reducing sugar consumption rate in the low-MWR group (2∶4) was about 3.4 times higher than that in the high-MWR group (2∶1), suggesting that higher moisture accelerated saccharification and fermentation initiation.Ethanol accumulation followed the opposite pattern:the 2∶2, 2∶3, and 2∶4 groups reached ethanol peaks about 150 mg/g on d5, whereas the 2∶1 group reached a lower peak (137.44 mg/g) on d7, with 13.20% less ethanol yield.This indicates that a moderate increase in system moisture effectively enhances ethanol production and shortens the fermentation period.The total content of volatile compounds also increased significantly with decreasing MWR, especially alcohols and esters, which approximately doubled, indicating that higher moisture promotes the synthesis and accumulation of flavor compounds.This study elucidates that MWR influences the fermentation efficiency and stability of semi-solid Baijiu by regulating heat and mass transfer characteristics and microbial metabolic activity, providing a theoretical basis for process optimization and quality control.

The quality of rice-flavor Baijiu is highly dependent on Xiaoqu fermentation.However, the microbial community in the traditional natural fermentation system is complex and greatly influenced by the environment, especially the stability of yeast community is easily affected.Among them, yeast can significantly affect the community dynamics and stability of the fermentation system by mediating resource competition and metabolic interaction, which leads to the difficulty in controlling flavor metabolism in the fermentation process and restricts the improvement of Baijiu quality.In order to solve the above problems, this study fortified the Xiaoqu by incorporating Pichia kudriavzevii and Wickerhamomyces anomalus during the traditional production process, and applied the fortified Xiaoqu in Baijiu fermentation.The results showed that the yeast diversity of fortified Xiaoqu was significantly increased, and the microbial community structure of the fermentation system could be effectively optimized after the application of fortified Xiaoqu.The network analysis showed that the microbial interaction increased during the fermentation process.Flavor detection and metabolic function prediction show that yeast-fortified Xiaoqu can significantly increase the content of esters in the fermentation system by enhancing the synthesis of carbonylesterase in yeast community.This study provides theoretical basis and technical support for the modernization of traditional fermentation technology of rice-flavor Baijiu.

To investigate the flavor evolution mechanism of Baijiu during the aging process, this study analyzed base liquor and finished product from the same Jiang-flavor type Baijiu enterprise, spanning the production years from 2010 to 2023.Headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry was employed, and the data was integrated with multivariate statistical analysis and odor activity value (OAV) calculations to dissect the differential characteristics of their chemical profiles and the changes in key flavor substances.The results indicated that while the volatile components in both base liquor and finished product underwent significant changes during aging, their evolution trends differed markedly.The base liquor exhibited a age-dependent pattern of "acid increase and ester decrease" along with a trend of component homogenization, whereas the finished product did not show similar regularity.Multivariate statistical analysis revealed that the potential aging markers for base liquor and finished product were distinct, yet both contained long-chain fatty acid esters.This suggests that the concentration changes of these substances may be more dependent on aging time than on production techniques or geographical origin, positioning them as potential universal aging markers for Baijiu.Furthermore, OAV analysis demonstrated that the OAVs of characteristic flavor compounds in the base liquor fluctuated drastically with age, while the changes in their counterparts in the finished product were relatively moderate, indicating a higher flavor stability for the latter during its shelf life.This research provides a theoretical basis for a deeper understanding of the Baijiu aging process.

To investigate the differences in the microbial community composition and physicochemical indices of Zaopei between ground-based mechanized airing and traditional manual airing in Jiangxiangxing Baijiu production, Illumina MiSeq sequencing was employed to analyze the microbial communities of Zaopei at different post-Airing stages.Correlation analyses were conducted to elucidate the relationships between the microbial communities and physicochemical indices.The results demonstrated that the Shannon index of microbial communities in Zaopei subjected to mechanized airing and Daqu mixing was significantly lower than that in traditionally manually airing Zaopei during the middle stage of stacking fermentation (P=0.037) and at the completion of stacking before cellar entry (P=0.005).Significant differences in β-diversity between mechanized and traditionally airing Zaopei were mainly observed at the mid-stacking stage (P=0.044) and the cellar-entry stage (P=0.006).These differences were primarily attributed to taxa such as Levilactobacillus (LDA=4.2), Companilactobacillus (LDA=2.5), and Paucilactobacillus (LDA=2.3).The relative abundance of fungi in mechanized airing Zaopei was generally higher than that in traditional airing Zaopei, with Paecilomyces (LDA=4.4), Saccharomycopsis (LDA=3.4), Kodamaea (LDA=3.3), and Starmerella (LDA=3.2) being significantly enriched.In contrast, only Candida (LDA=3.3) and Cyberlindnera (LDA=3.1) showed higher relative abundances in the traditional airing group.Mantel test analysis further revealed that microbial communities under mechanized airing were enriched in taxa associated with starch hydrolysis and reducing sugar consumption, whereas those under traditional cooling were more closely associated with taxa involved in the metabolism of Baijiu volatile flavor compounds.This study provides theoretical and data support for the screening of functional microorganisms and the optimization of mechanized production technologies in Jiangxiangxing Baijiu brewing.

This study investigated the effects of cellar age on the spatial distribution of fermented grains (Zaopei) characteristics and key flavor components in raw liquor within mechanized strong-flavor Baijiu fermentation pits.Samples were systematically collected from the upper, middle, and lower layers of pits with varying ages (11, 5, and 4 years).Physicochemical analysis and gas chromatography revealed increasing trends for multiple indicators along the depth gradient, with some being statistically significant (P<0.05).Principal component analysis was employed to extract key indicators, and linear regression quantified the strength of gradient changes.The results showed that 11-year-old pits exhibited stable and highly predictable increasing trends for most indicators.Specifically, the concentrations of ethyl caproate, sec-butanol, n-propanol, ethyl butyrate, and n-butanol demonstrated a highly significant linear increase (P<0.01) from the upper to the lower layers.In contrast, 5-year-old and 4-year-old pits showed weaker or less consistent spatial patterns.These findings demonstrate that increasing cellar age is a key driver in shaping the spatial heterogeneity and stability of the pit microecology.As pits mature, their internal microenvironment stabilizes, leading to more ordered metabolic pathways for flavor formation.This study provides a theoretical basis for assessing and regulating pit quality under mechanized brewing conditions.

To investigate the effects of different probiotics on the quality and flavor of fermented Cyclocarya paliurus beverage, C.paliurus was used as the raw material.Fermented beverages were prepared by mono-fermentation with yeast or lactic acid bacteria, as well as co-fermentation (with non-fermented beverage as control).The effects of different fermentation methods on physicochemical indexes, bioactive components, antioxidant capacity, free amino acids, volatile flavor compounds, and sensory quality were systematically compared using physicochemical analysis, electronic nose, headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry, and sensory evaluation.The results showed that after fermentation, pH decreased significantly, total acid increased, and soluble solids decreased.Compared with the non-fermented group, all three fermentation methods significantly increased the contents of total flavonoids, total triterpenoids, and total polysaccharides, as well as the antioxidant capacity, with the co-fermentation group showing the best performance.The co-fermentation group exhibited the highest total free amino acid content (208.91 μg/mL), and the γ-aminobutyric acid content reached 12.07 μg/mL.The co-fermentation group also had the highest total volatile compound content (451.351 μg/mL), in which key flavor substances such as damascenone (1 380.00), ethyl butyrate (549.00), and ethyl 2-methylbutyrate (520.13) contributed prominently, imparting intense floral, fruity, and sweet notes.Sensory evaluation results showed that the co-fermentation group received the highest sensory score, with the best coordination of color, taste, aroma, and texture.In conclusion, co-fermentation with yeast and lactic acid bacteria can effectively improve the flavor quality and functional characteristics of fermented C.paliurus beverage, representing a promising processing method with good application potential.

To investigate the effects of fermentation technology on the quality of chili sauce, this study screened 12 lactic acid bacteria strains for chili sauce fermentation based on extensive previous literature research and preliminary experimental data.The acid-producing characteristics of chili sauce fermented by different strains were evaluated, and the differences in the types of volatile flavor compounds were analyzed using GC-MS.Combined with the acid-producing and flavor profiles, strains with superior fermentation performance were selected.Based on the screening results, a single-factor experiment combined with the Box-Behnken response surface methodology was further employed to systematically analyze the effects of mixed strain ratio, fermentation time, and inoculation amount on the total acid content and pH value of fermented chili sauce.Additionally, the flavor characteristics of fermented chili sauce were analyzed using an electronic nose combined with human sensory evaluation.The results showed that among the 12 lactic acid bacteria strains, Lactobacillus paracasei CCFM1074, Lactiplantibacillus plantarum Lp-G18, and Lactobacillus helveticus RE-78 exhibited excellent acid-producing capacity, after 5 days of fermentation, the pH value of chili sauce rapidly decreased from 4.50 to approximately 3.85, and the total acid content increased from 1 g/100 g to 2.8 g/100 g.Lactobacillus gasseri LG-G12 produced the highest number of volatile flavor compounds (73 types).Through single-factor experiments and response surface optimization, the optimal fermentation conditions for the 4 selected strains were determined as follows:mixed strain ratio of 2∶2∶3∶1, inoculation amount of 0.076%, and fermentation time of 6 days.Under these conditions, the product showed appropriate total acid content (2.95±0.05) g/100 g and stable pH (3.8±0.03).E-nose analysis (principal component analysis and aroma radar chart) was performed on three samples:unfermented chili sauce, chili sauce fermented under the optimal conditions, and traditionally fermented chili sauce (3 months).The results indicated significant differences in the composition of volatile flavor compounds among the three samples, with distinct clustering separation.Characteristic flavor compounds (e.g., esters and acids) exhibited regular changes during the fermentation process. Sensory evaluation showed that the flavor of chili sauce fermented by the optimized process was relatively close to that of traditionally fermented chili sauce.This study provides technical and theoretical support for the industrial production and directional flavor regulation of fermented chili sauce.

To investigate the flavor enhancement of chopped chili pepper by eight ester-producing yeast strains, the physicochemical and volatile profiling analyses coupled with multivariate statistics were employed, leading to the identification of the most aroma-active strains.Results showed that M1, M3, M5, M6, and M8 exhibit greater ester production than the other strains.Compared to natural fermentation, inoculated fermentation led to reductions in total acid and amino acid nitrogen content, as well as obvious decrease in reducing sugar and total sugar levels.Further, higher contents of esters and hydrocarbons were observed in inoculated fermentation compared to natural fermentation, with samples M3 and M8 exhibiting 5.50- and 5.98-fold increases in esters content, respectively.Additionally, a distinct separation of the M3 and M8 samples from others was indicated by cluster analysis and partial least squares discrimination analysis (PLS-DA).Furthermore, samples M3 and M8 not only introduced twelve new aromatic compounds, such as ethyl salicylate, but also significantly increased the concentration of key aroma substances including methyl salicylate, ethyl palmitate, linalool, myristaldehyde, and pentadecanal.Based on ITS sequence analysis, M3 was classified as Zygosaccharomyces rouxii and M8 was classified as Wickerhamiella versatilis. The findings could provide a valuable insights for improving the flavor of fermented chili products through targeted yeast inoculation.

Baogu Suan, a typical plant-based fermented food made primarily from corn flour and fresh red chili in Southwest China, shows notable variations in microecology and quality formation due to differences in raw material ratios.To clarify the regulatory role of fresh red chili addition, this study prepared three treatments with chili-to-corn flour mass ratios of 0.8∶1, 1∶1, and 1.2∶1.The experiment monitored physicochemical parameters throughout fermentation and characterized quality attributes and bacterial community succession using sensory evaluation and Illumina NovaSeq sequencing.Results showed that pH declined continuously and lactic acid accumulated steadily, with acidification accelerating as chili ratios increased.Firmicutes dominated all samples in the late fermentation stage (relative abundance>98%).Microbial succession patterns differed among treatments:in the high-chili group (1.2∶1), the genus Companilactobacillus maintained high relative abundance (> 80%) from the early stage, accompanying rapid sugar reduction and accelerated acid production.The low- and medium-chili groups showed a gradual shift from plant-associated bacteria such as Pantoea and early-colonizing lactic acid bacteria to dominant lactic acid bacteria.β-diversity analysis indicated that the high-chili group achieved a stable community structure earlier.Although the high-chili group showed stronger microbial dominance and faster acidification kinetics, descriptive sensory evaluation revealed that the medium-chili group (1∶1) presented a more balanced and desirable flavor profile.These findings suggest that chili proportion regulates microbial succession and quality formation by altering environmental selection pressure, and provide scientific support for process optimization and quality-oriented product development.

To enhance the fermentation performance of buckwheat dough, this study systematically investigated the impacts of magnetic field-assisted fermentation on water migration and protein molecular structure in buckwheat dough by employing low-field nuclear magnetic resonance, Fourier transform infrared spectroscopy, and texture profile analysis.The results demonstrated that with increasing magnetic field strength, the fermentation volume of the dough first increased;however, when the strength exceeded a certain threshold, further increases led to a reduction.Among all tested intensities, 1 mT exhibited the most pronounced effects on the fermentation capacity and rheological properties of buckwheat dough.At this intensity, the fermentation volume of buckwheat dough increased by 21.1%, concurrent with a decrease in free water content and an increase in bound water content.Simultaneously, the α-helix content of the dough protein attained a maximum of 36.5%.When the intensity exceeded this value, the α-helix content decreased, whereas the random coil content increased to 23.5%.The specific volume of the resulting buckwheat steamed bread ranged from 1.6 to 1.9 mL/g, representing an 18.7% increase compared to the control group.Additionally, the hardness of buckwheat steamed bread decreased by 46.4%, 42.3%, and 30.5%, respectively.In conclusion, appropriate magnetic field treatment optimizes the uniformity of water distribution in buckwheat dough, regulates the protein molecular structure, strengthens the stability of the protein network, and facilitates water migration-ultimately enhancing the fermentation capacity of buckwheat dough as well as the specific volume and textural properties of buckwheat steamed bread.

Traditional Jiaozi (a dough fermentation starter for steamed bread making) production relies on natural fermentation, which often results in unstable microbiota and inconsistent fermentation performance, ultimately compromising the quality of the steamed bread.To investigate the potential of EPS-producing lactic acid bacteria (LAB) in improving Jiaozi quality, this study involved preparing a sorghum-based Jiaozi using a co-culture of EPS-producing Weissella cibaria and Saccharomyces cerevisiae. The microbial counts, extracellular exopolysaccharide (EPS) content and acidity of sorghum-based Jiaozi prepared at different incubation times were first investigated.Then the fermentation capacity, quality and storage characteristics of the steamed bread made from sorghum-based Jiaozi were evaluated and compared with those of control Jiaozi prepared from the S. cerevisiae mono-culture.The results indicate that the optimal preparation time for producing sorghum-based Jiaozi is 36 h.The counts of LAB and yeast in the Jiaozi starter were 8.60, 8.58 lg CFU/g respectively, with a titratable acidity of 17.79 mL.The EPS content was 9.97 mg/g.The volume of the dough fermented by the sorghum-based Jiaozi increased by more than double, which was similar to control Jiaozi prepared from the S. cerevisiae mono-culture.There was no significant difference in the specific volume of steamed bread produced by the sorghum-based Jiaozi compared to the control group, and both met national standards.Additionally, steamed bread prepared using sorghum-based Jiaozi exhibited higher elasticity (89.33%), with slower rates of hardening and moisture loss during storage.In summary, sorghum Jiaozi prepared using EPS-producing W. cibaria exhibits excellent quality characteristics and application properties, demonstrating its potential as a steamed bread fermentation agent.

This study used ultrasonic-modified quinoa bran soluble dietary fiber (U-QSDF) and whey protein as wall materials to prepare Lactiplantibacillus plantarum L4-11 microcapsules through complex coacervation and emulsification, and analyzed the wall material characteristics and probiotic activity.At pH 2.75, stable complex coacervates were obtained by blending U-QSDF with whey protein at 1∶3.Infrared spectroscopy and X-ray diffraction analysis confirmed that the two components bound via electrostatic interactions, and the complex coacervation process did not alter their structural characteristics.The complex coacervates significantly enhanced emulsion stability through the anionic properties of U-QSDF and the amphiphilic characteristics of its two components.When U-QSDF/whey protein complex coacervates were used as outer aqueous phase (W₂) of the W₁/O/W₂ emulsion, the emulsion achieved steady-state equilibrium with 6% PGPR added to the oil phase, W₁∶O ratio of 1∶2, and W₁/O∶W₂ ratio of 1∶8.Under the optimal preparation conditions for U-QSDF/whey protein complex coacervation, the encapsulation efficiency of L.plantarum L4-11 was 66.26%, with a particle size of (155.63±1.46) μm. Under the optimal preparation conditions for the double emulsion system, the encapsulation efficiency reached 84.33%, with a particle size of (245.93±1.56) μm.In vitro gastrointestinal simulation and storage stability demonstrated that complex coacervate microcapsule and W/O/W emulsion system enhanced the viability of L.plantarum L4-11.This study lays the theoretical foundation for developing probiotic delivery systems using U-QSDF/whey protein complex coacervates and creating highly effective and stable functional probiotic products.

In order to obtain a W/O/W double emulsion that co-encapsulates epigallocatechin-3-gallate (EGCG) and quercetin (Q).In this study, pea protein isolate (PPI) was used as the hydrophilic emulsifier in the outer aqueous phase, and polyglycerol polyricinoleate (PGPR) was used as the lipophilic emulsifier in the oil phase.The optimal scheme for double emulsion:the mass fraction of PPI in the outer aqueous phase is 6%, the mass fraction of PGPR in the oil phase is 4%, the mass fraction of NaCl is 1.0%, the volume ratio of the inner aqueous phase to the oil phase (W₁∶O) is 3∶7, and the volume ratio of the primary emulsion-outer aqueous phase (W₁/O∶W₂) is 4∶6.The W/O/W double emulsion prepared under this scheme had good stability and excellent encapsulation ability (EGCG:65.12%, Q:89.48%).The results provide a reference for the construction of co-encapsulation systems for bioactive compounds, and further expand the application of W/O/W emulsion in food.

In this study, we employed freeze-thawing as a pre-treatment for corn starch, followed by enzymatic hydrolysis to prepare porous starch (FTS-EN), which was subsequently used to encapsulate ferulic acid (FTS-EN-FA).The encapsulation potential of FTS-EN was evaluated on the basis of microscopic observation, adsorption performance, and low-temperature nitrogen adsorption experiments.In addition, we determined the particle morphology, encapsulation efficiency/loading capacity, stability, antioxidant properties, and in vitro simulated digestion of the ferulic acid-loaded samples.The results revealed that compared with the control group, the porous starch obtained via enzymatic hydrolysis following initial freeze-thaw treatment was characterized by a larger number number of pores, along with a significantly higher absorption of water (124.65%) and oil (102.87%).Furthermore, there were significant enhancements regarding the surface area, pore volume, and average pore size of this modified starch (P<0.05), and following the encapsulation of ferulic acid, we recorded a significant 2.27-fold increase in the loading capacity of FTS-EN-FA compared with that of the control material (P<0.05).In response to differing light exposure days, temperatures, and storage durations, FTS-EN-FA was found to be characterized by the highest retention of ferulic acid and showed enhanced stability.Moreover, the antioxidant activity of FTS-EN-FA was significantly superior to that of other control groups (P<0.05), and also had favorable sustained-release capacities in simulated gastric and intestinal fluids.In conclusion, the combined freeze-thaw and enzymatic hydrolysis approach for preparing porous starch can contribute to significant enhancements in its adsorptive performance, as well as enhancing the encapsulation efficiency, stability, and in vitro sustained-release properties of ferulic acid.

To address the issues of insufficient hardness and poor texture stability of single soy protein isolate (SPI) gels, this study used SPI and high methoxyl citrus pectin (HMP) as raw materials to optimize the preparation process of composite gels via single-factor experiments and systematically investigate the effects of HMP addition on their functional properties and molecular interaction mechanisms.The results showed that the optimal processing conditions for the composite gel were a heating temperature of 85 ℃, an SPI addition amount of 2.50 g, and an HMP addition amount of 0.08 g, under which SPI and HMP formed a three-dimensional network structure with significant synergistic effects.When the HMP addition is 3.2% of the SPI mass, the gel exhibited the best comprehensive performance:the water holding capacity reached 86.09%, an increase of 11.5% compared with the group without HMP;hardness, springiness, and chewiness increased by 29.3%, 18.7%, and 32.5% respectively compared with the control group, and the L^* value (brightness) reached a peak of 60.07.Mechanistic analysis revealed that HMP bound to SPI through hydrogen bonds, hydrophobic interactions, and electrostatic attraction, promoting the transformation of SPI secondary structure from α-helix (16.86% to 12.00%) to β-sheet (32.45% to 38.01%), which significantly increased intermolecular cross-linking density.This study clarified the processing parameters and property regulation mechanism of SPI-HMP composite gels, providing a theoretical basis and technical reference for texture improvement of plant-based meat products.

In order to reduce the addition of phosphate in processed meat products, the application of dietary fiber in low phosphorus meat products was developed.In this study, on the basis of adding 3.0% (w/w) inulin, the effects of different concentrations of citrus fiber (0.5%, 1.0%, 1.5%, and 2.0%, w/w) on the total sulfhydryl content, secondary structure, SDS-PAGE, gel water distribution and water holding capacity of mutton myofibrillar protein were investigated, and the mechanism of water retention and protein structure change of mutton protein was explored.The results showed that compared with the 0.3% phosphate control group, the addition of 3.0% inulin combined with 1.5% citrus fiber significantly reduced the total sulfhydryl content, surface hydrophobicity and fluorescence intensity of the protein (P<0.05), promoted the transformation of the secondary structure of the protein from α-helix to β-sheet structure, which was promoted the the formation of gel three-dimensional network structure and the conversion of free water to immobilized water, and significantly improved the water retention of the gel (P<0.05).However, when the addition amount of citrus fiber was 2.0%, the protein was excessively aggregated, the gel structure was loose, and the water retention decreased.In summary, the addition of 3.0% inulin combined with 1.5% citrus fiber can effectively improve the structure of mutton protein and improve the water retention of gel.The combination of two dietary fibers has the potential to become a new type of phosphate substitute.

This study aimed to investigate the antioxidant activity of Eucommia ulmoides leaf extract (EULE) and its regulatory effects on the structure and emulsifying functional properties of chicken myofibrillar proteins (MPs) oxidized by the Fenton system, thereby providing a theoretical basis for the application of natural antioxidants in meat products.EULE exhibited concentration-dependent scavenging activities against ·OH, ABTS cationic free radical, and DPPH free radicals.The experiment was designed with a blank control, an oxidation control, and EULE treatment groups at concentrations of 0.2, 0.6, and 1 mg/mL, and systematic determinations were conducted on indicators including MPs structure and emulsion functional properties.The results showed that oxidative treatment significantly increased the carbonyl content and decreased the sulfhydryl content of MPs, reduced the α-helix proportion while increasing the content of disordered structures (P<0.05), enhanced surface hydrophobicity, decreased fluorescence intensity, and caused an imbalance in intermolecular forces.Concurrently, oxidation led to an increase in emulsion particle size, a reduction in the absolute value of zeta potential, and deterioration in emulsifying and rheological properties.EULE at 0.6 mg/mL effectively scavenged reactive oxygen species, reduced carbonyl formation and sulfhydryl loss, improved the α-helix proportion, regulated surface hydrophobicity and fluorescence characteristics, and optimized the distribution of intermolecular forces.Meanwhile, it reduced emulsion particle size, increased the absolute value of zeta potential, enhanced emulsifying and rheological properties, and maintained good stability during 12 h of storage at 4 ℃.However, EULE at 1 mg/mL exerted negative effects:despite its antioxidant capacity, the excessive concentration may have induced abnormal aggregation and cross-linking of protein molecules, resulting in structural disorder and functional deterioration.This study reveals the regulatory mechanism of EULE, which synergistically maintains the balance between MPs structure and intermolecular forces through non-covalent interactions and the regulation of covalent cross-linking under oxidative stress.These findings provide a core basis for the targeted application of EULE in the quality improvement of meat emulsion products.

Edible bird's nest (EBN) requires boiling prior to consumption, and its morphology, structure and texture are significantly influenced by thermal processing.This study investigated the gel-to-sol transition of EBN proteins and the digestive properties of instant EBN as a function of boiling duration (0-120 min).The results showed that the swelling ratio reached a peak of 241.38% at 25 minutes of boiling.During this period, EBN proteins were fully unfolded, with the β-sheet content increasing from 48.36% to 52.48%.Hydrophilic binding sites (e.g., serine and threonine residues) were exposed, leading to the formation of a hydrated gel network through hydrogen bonding and hydrophobic interactions.Scanning electron microscopy revealed that the surface of instant EBN exhibited uniform and dense pores, resulting in a maximum rehydration ratio of 31.37-fold and the softest texture.After 30 minutes of heating, electrophoresis indicated the onset of protein aggregation.Continued heating from 40 to 120 minutes caused peptide bond cleavage and degradation of structural proteins, inducing a transition from a hydrogel to a liquid sol, accompanied by a decrease in the swelling ratio and significant deterioration in rehydration ratio and hardness of the instant product.Simulated gastric digestion confirmed that the 25 min treatment group exhibited the most balanced protein release (2.62 mg/mL) and solid retention (10.53%).In contrast, instant EBN prepared with prolonged boiling still maintained larger molecular weight protein subunits after digestion, indicating low digestive utilization.This study elucidates the solation process of EBN proteins from gel network formation to thermal degradation of peptide chains, providing a theoretical basis for the development of instant EBN products and the thermal processing of protein-rich gel foods.

This study modified acorn starch using dynamic high-pressure microfluidization (DHPM) technology.It investigated the structure and physicochemical properties of acorn starch before and after modification via Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, rapid viscosity analyzer, and differential scanning calorimetry.The results showed that DHPM reduced the particle size distribution of acorn starch through shear, collision, high pressure, cavitation effects, and other mechanisms.It mainly acted on the relatively loose amorphous regions and imperfect crystalline regions, and partially reconstructed the double-helical structure of starch molecules, but did not change the functional groups or crystal type of acorn starch.With the increase of DHPM treatment pressure, the multi-scale structure of acorn starch changed.Compared with the untreated group, the median particle size of acorn starch treated at 80 MPa decreased from 13.47 μm to 10.87 μm, and the specific surface area increased from 704.03 m²/kg to 865.50 m²/kg.When treated at 120 MPa, holes and partial fragmentation appeared on the particle surface.After DHPM treatment, acorn starch exhibited enhanced water-holding capacity and freeze-thaw stability, reduced retrogradation rate and pasting temperature, and improved anti-retrogradation ability.In conclusion, dynamic high-pressure microfluidization effectively modulates the multiscale structure of acorn starch, thereby improving its physicochemical properties and expanding its potential applications in the food industry.

To investigate the impact of cream raw material on the flavor profile of sour cream, this study prepared samples using fresh cream and butter as raw materials, respectively.The flavor profiles were characterized using an electronic nose and electronic tongue.The composition of volatile compounds was determined by gas chromatography-ion mobility spectrometry (GC-IMS), combined with sensory evaluation for systematic analysis.The results showed that there were significant differences in the odor and taste characteristics of sour creams derived from different cream raw materials (P<0.05).GC-IMS analysis identified a total of 59 volatile compounds and 11 key aroma compounds, with aliphatic aldehydes and methyl ketones being the primary differential compounds contributing to the distinct flavors.Furthermore, the dairy-based sour cream exhibited superior sensory quality.This study comprehensively elucidated the impact of cream raw material on the flavor profile of sour cream, providing theoretical and practical guidance for optimizing product quality and regulating flavor.

Wild and cultured Larimichthys crocea differ in habitat, feeding patterns, and physiological activities, which may lead to variations in muscle quality and metabolic characteristics.In this study, back and abdominal muscles from wild and cultured L.crocea were analyzed using liquid chromatography-mass spectrometry-based non-targeted metabolomics to compare metabolic profiles and enriched pathways.The results showed abundant differential metabolites between two groups, with the largest number identified between the back muscle of wild fish and the abdominal muscle of cultured fish (188 metabolites).Principal component analysis and orthogonal partial least squares discriminant analysis effectively distinguished wild from cultured samples without model overfitting.Hierarchical clustering revealed that wild fish were enriched in cis-4-hydroxy-L-proline and phosphatidylcholines, whereas cultured fish contained higher levels of lipid derivatives and small molecules associated with feed additives or aquaculture environments.KEGG pathway analysis indicated that differential metabolites were mainly involved in amino acid metabolism, lipid metabolism, and energy metabolism.These findings suggest that the superior muscle quality of wild L.crocea is closely related to natural feeding and swimming activity, while adjusting feed composition and aquaculture conditions may help optimize metabolic pathways and improve the sensory and nutritional qualities of cultured fish.This study provides a molecular basis for quality evaluation and the optimization of farming strategies forL.crocea.

The Maillard reaction plays a crucial role in food processing and contributes positively to enhancing food flavor.This study aims to explore the effects of the Maillard reaction on the physicochemical properties and flavor characteristics of Cymbium pepo hydrolysate.Using C.pepo hydrolysate and four reducing sugars as raw materials.Investigate the changes in the physicochemical properties of the Maillard reaction products, including intermediate products, browning intensity, the degree of graft, and free amino acids.Meanwhile, the flavor and taste changes of Maillard reaction products were analyzed using gas chromatography-ion mobility spectrometry (GC-IMS), electronic tongue, and sensory evaluation.The results showed that after the Maillard reaction, the intermediate products, browning intensity, the degree of graft, and antioxidant activities of the reaction products significantly increased.The bitter amino acids in the hydrolysate were reduced, and the color and flavor characteristics of the hydrolysate were improved.Meanwhile, the electronic tongue can effectively distinguish the taste differences of various reaction products.A total of 38 volatile compounds were identified in the hydrolysate and Maillard reaction products by GC-IMS.The Maillard reaction products generated more substances such as pyrazines and furans, reducing aldehyde compounds, thereby enhancing the aroma of roasted meat and nuts, and diminishing unpleasant flavors such as fishiness.This study provided novel insights into enhancing the flavor of C.pepo hydrolysate, providing a theoretical basis for the development of flavored products.

The study investigated the impact of vacuum ice temperature drying on the quality of grass carp surimi powder, and the gel strength, water retention, protein secondary structure, fat oxidation and microbial number of each group were tested, comparing to the control groups of hot air drying and vacuum freeze drying.The results revealed that the gel strength of surimi powder dried at ice temperature (173 g·cm) was significantly higher than the other groups (P<0.05).In comparison to the gel strength of fresh fish (207 g·cm), the gel strength of vacuum ice temperature dried fish powder decreased by 16.4%,while it decreased by 75.8% and 27.5% in hot air dried and vacuum freeze dried fish powder respectively.Among the three drying methods, the gel prepared by vacuum ice temperature drying surimi powder exhibited the highest water retention rate of 81%, which was 9% higher than hot air drying and 3% higher than vacuum freeze drying.Additionally, it demonstrated the best water combination ability.Fourier transform infrared spectroscopy showed that vacuum ice temperature drying had the lowest damage to the secondary structure of gel protein compared with other groups.In terms of microstructure, the gel network structure prepared by vacuum ice temperature-dried surimi powder was the closest to that of fresh surimi gel.There were more holes in the vacuum freeze-dried surimi powder, while the gel network structure of hot-air dried surimi powder was seriously damaged.Both vacuum ice temperature and vacuum freeze drying can inhibit the propagation of microorganisms, and the fat oxidation degree of vacuum ice temperature dried surimi meal is the lowest.In conclusion, the gel quality of vacuum ice temperature dried surimi powder is better.

The quality of frozen pre-made roasted fish is prone to deterioration due to changes in moisture content and state during freezing and storage.To improve the quality of frozen pre-made roasted fish, a four-factor experimental system composed of fish collagen peptide, transglutaminase(TGase), trehalose and sorbitol was constructed.GA-BP neural network combined with a response surface model was employed to model and optimize the formulation of the compounded water-holding agent.The freezing curve, water-holding capacity, microstructure, and moisture state of the samples were comprehensively evaluated following the addition of the compound water-holding agent.The results showed that the prediction accuracy of the GA-BP neural network model was better than that of the response surface model (R²=0.958 9).The validation experiments showed that the optimal formulation was 2.65% (mass fraction) of fish collagen peptide addition, 0.43% of TGase, 1.13% of trehalose, and 0.31% of sorbitol.Under this formulation, the moisture content of the frozen pre-made roasted fish is (73.76±0.31)%.The loss rates of thawing, centrifugation and cooking of the sample with added the compound water-holding agent decreased by 4.24%, 3.18%, and 1.82%, respectively, compared to the sample without added.Low-field nuclear magnetic resonance analysis showed that the roasted fish added the compound water-holding agent had a smaller percentage of migration of its immobile water to free water during freezing.Scanning electron microscopy observation revealed that the compound water-holding agent could promote the aggregation cross-linking of myofibers and reduce the formation of myofibrillar interstitial space.The above result indicated that the water-holding agent developed in this study had good quality retention effect.

To investigate the effects of different cooling methods on the preservation quality of braised pork during storage and transportation, this study employed natural cooling, vacuum cooling, and static magnetic field-assisted vacuum cooling to treat braised pork.The changes in various physicochemical indicators, microbial growth, and water distribution were analyzed before and after 10-day refrigeration at 4 ℃.Results demonstrated that after storage, all cooling treatment groups showed increased total viable counts, total volatile basic nitrogen, and malondialdehyde content, while exhibiting decreased moisture content and water-holding capacity, along with altered color and textural properties.Among them, both vacuum-cooled and static magnetic field-assisted vacuum-cooled groups exhibited significantly lower total viable counts compared to natural cooling group before and after storage.Notably, the static magnetic field-assisted vacuum cooling group demonstrated significantly lower pH, total volatile basic nitrogen, and malondialdehyde content compared to both natural cooling and vacuum cooling groups after storage.Additionally, the vacuum cooling group exhibited lower moisture content, with the smallest L^* value (lightness) and largest a^* value (redness) among all treatment groups.Low-field nuclear magnetic resonance analysis revealed that vacuum cooling increased the proportion of bound water in the skin layer and immobilized water in the lean pork.Notably, static magnetic field-assisted vacuum cooling suppressed the conversion of immobilized water to free water, better maintaining myofibrillar protein water-binding characteristics, which contributed to improved braised pork quality preservation.This study provides a new idea to address quality deterioration caused by the slow cooling of thermally processed meat dishes.

To investigate the effects of different harvest periods on the quality of Zhuxue peaches, this study measured 26 quality indicators of Zhuxue peach fruits harvested at three harvest periods (S1, S2, S3), including sensory quality, nutritional quality, and juice processing quality.Correlation analysis and principal component analysis were used for comprehensive evaluation.The results showed that different harvest periods had a significant effect on the quality of Zhuxue peaches.As harvest periods were delayed, the peel L^* value decreased gradually, while the pulp L^* value first increased and then decreased.The a^*value for both peel and pulp showed an increasing trend, and the b^* value had no significant change.The contents of total soluble solids and titratable acidity first increased and then decreased, while hardness and the contents of most nutritional components (fructose, glucose, citric acid, ascorbic acid, total phenols, flavonoids, anthocyanins) decreased.The L^* and b^* values of the juice decreased significantly, while the a^* value increased gradually.Turbidity increased significantly, and transmittance decreased significantly.During harvest period S2, juice yield was highest and browning was lowest.Correlation analysis indicated that fructose content, citric acid content, anthocyanin content, and juice transmittance were core correlated indicators.Principal component analysis results showed that four principal components could represent 93.346% of the information from the original indicators.Based on the mathematical model, the comprehensive quality ranking of Zhuxue peaches at different harvest periods was:S1>S2>S3.Therefore, Zhuxue peaches harvested during period S1 exhibited optimal quality.This study provides a theoretical reference for quality evaluation and scientific harvesting of Zhuxue peaches.

This study systematically investigated the differences in processing characteristics of Cili (Rosa roxburghii) fruits from different varieties and geographical origins in Guizhou Province, aiming to provide a theoretical basis for the classification and high-value utilization of Cili resources.A total of 91 cultivated and wild Cili samples were collected from Guiyang, Liupanshui, Bijie, Qiannan, and other areas in Guizhou.Their physicochemical indices, nutritional qualities, and antioxidant activities were systematically determined, followed by a comprehensive evaluation using principal component analysis (PCA) and cluster analysis (CA).The results indicated significant differences (P<0.05) in all measured indices among Cili from different varieties and origins.Specifically, the Anshun Jincili exhibited the highest total soluble solids and titratable acid contents, while the Cili from Zunyi showed the most prominent vitamin C content.PCA revealed that the Cili from Zunyi, Thornless Cili from Guiyang, and Wild-1 from Duyun possessed superior overall quality.CA classified the 91 germplasm resources into three distinct categories.Based on the characteristics of each category, targeted processing strategies were proposed:Category Ⅰ (e.g., DY-32, DY-33), with balanced quality, is suitable for developing leisure foods such as fruit cakes and fruit teas.Category Ⅱ (e.g., ZY, GY2), rich in active components, is appropriate for producing health products and functional cosmetics.Category Ⅲ (e.g., DY-14, DY-15, DY-19), with strong antioxidant activity, is ideal for processing into natural antioxidants.This study confirms the necessity of classification-based processing by variety and origin to promote the precise, high-quality development of the Cili industry in Guizhou.

Taking the 2025 national Baijiu taster training samples as the experimental object, the gas chromatography, near-infrared spectroscopy technology combined with machine learning were used to analyze the different flavor substances of different flavor types, origins and quality grades of Baijiu, and to construct the discrimination model.The results showed that PLS-DA could effectively distinguish the characteristics of different types of Baijiu flavor substances.Taking VIP value >1, P<0.05 as the standard, 21 kinds of Baijiu with different flavor types were identified as β-phenylethyl alcohol, n-butanol, acetal, etc;27 kinds of Jiangxiangxing Baijiu from different regions were identified as ethyl palmitate, β-phenylethanol, ethyl oleate, etc;21 kinds of volatile flavor compounds such as isobutanol, β-phenylethanol, diethyl succinate, etc;and 14 kinds of volatile flavor compounds such as n-pentanol, methanol and isobutyraldehyde were identified as important contribution to different quality grades of Qingxiangxing Baijiu.Compared with RF and SVM, GA-BP model has excellent discrimination performance for different flavor types, origins and quality grades of Baijiu, and the classification accuracy of test samples is 91.33%, 94.38%, 98.28% and 94.83%, respectively.The SHAP interpretation results showed that the wave numbers of 11 996、7 383、5 952,7 128、5 848、5 311,6 935、6 932、5 319,11 996、5 902、5 824 cm^-1 had a higher contribution to the model output, and were determined to be the key spectral points for predicting different types of Baijiu.The near-infrared spectroscopy combined with GA-BP model proposed in this study has a high accuracy in the discrimination of different types of Baijiu, which provides a theoretical reference for the rapid traceability and the scientific evaluation of different types of Baijiu.

To investigate the effect of drying temperature on the flavor of Cantonese sausages, electronic nose, electronic tongue, and gas chromatography-mass spectrometry (GC-MS) were employed to analyze the flavor profiles of Cantonese sausages dried at high temperature (HG) and low temperature (LG).Radar chart construction, principal component analysis, and partial least squares-discriminant analysis (PLS-DA) were used to evaluate the flavor differences between the 2 groups.The results showed that LG exhibited stronger responses to volatile components such as sulfur-containing and nitrogen-oxygen compounds, while HG presented significantly higher bitterness, astringency, and their aftertaste values.No significant differences were observed in sourness, umami, or richness between the two groups.Additionally, LG had significantly higher contents of umami and sweet amino acids, along with lower levels of bitter and tasteless amino acids, compared to HG.Regarding fatty acid composition, LG contained a significantly higher proportion of saturated fatty acids, whereas HG had a higher content of polyunsaturated fatty acids.A total of 29 and 33 volatile compounds were identified in HG and LG by GC-MS, respectively.PLS-DA screening revealed 1 amino acid (glutamic acid), 5 fatty acids (oleic acid, stearic acid, linoleic acid, palmitic acid, palmitoleic acid), and 11 volatile compounds (phellandrene, (-)-isocaryophyllene, myrcene, methyl butyrate, β-terpinene, ethyl butyrate, 3-carene, isoamyl alcohol, ethyl caprylate, ethyl acetate, and methyl isopentyl ether) as the characteristic flavor substances distinguishing the 2 types of sausages.In conclusion, drying temperature regulated the amino acid composition, fatty acid distribution, and volatile compound profile to achieve precise modulation of the flavor of Cantonese sausages.This study provides important theoretical support for the optimization of process parameters based on target flavors in industrial production.

This study developed a method based on ultra-performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) to achieve simultaneous analysis of multiple non-volatile components in tea.A solution of 0.1% formic acid-50% methanol (volume fraction) was used as the extraction solvent for the ultrasonic-assisted simultaneous extraction of 29 target compounds, including catechins, amino acids, and alkaloids.After systematic optimization, a Hypersil GOLD column (150 mm×2.1 mm, 1.9 μm) was used, with a gradient elution of 0.1% formic acid water (volume fraction) and methanol as the mobile phase.The simultaneous separation and identification of catechins, alkaloids, and amino acids were achieved under positive and negative ion switching modes.Method validation showed good linearity (R²>0.988 7) for all analytes within their respective concentration ranges.The average recoveries at three spiked levels ranged from 80.77% to 117.23%, with relative standard deviations between 0.59% and 9.81%.These results indicated that the method provided high accuracy, repeatability, and stability.The established method was successfully applied to real tea samples.Based on the contents of the 29 components, principal component analysis was performed, extracting five principal components with a cumulative variance contribution rate of 97.39%.A comprehensive quality evaluation model for tea was subsequently constructed.This method is simple, sensitive, and suitable for simultaneous determination and quality assessment of multiple components in tea, providing a valuable reference for tea quality control and standardized evaluation.

The bidirectional regulation between gut microbiota and polyphenols from medicine and food homologous (MFH) plants serves as a critical theoretical entry point for elucidating the health benefits of natural products.The biochemical pathways through which gut microbiota transform polyphenols into highly bioactive metabolites via deglycosylation, ring cleavage, and reduction are systematically characterized.Furthermore, the molecular mechanisms by which polyphenols selectively remodel microbiota structure, maintain intestinal barrier integrity, and modulate gut-organ axis signaling via prebiotic-like effects are explored.Emphasizing the bidirectional potential of polyphenol metabolites in microbiota modulation provides a solid theoretical foundation for the precision utilization of MFH resources and the development of innovative functional foods.

Yeast β-glucan, a naturally abundant functional food ingredient, has been extensively utilized in the food industry.This review summarizes the extraction methods of yeast β-glucan, including physical, chemical, enzymatic, and combined approaches, as well as purification techniques such as precipitation, dialysis, ultrafiltration, and chromatography.Additionally, the applications of yeast β-glucan in meat products, dairy products, beverages, baked goods, and functional foods are discussed, with a focus on its improvements to food quality and functional properties.Challenges in current research on yeast β-glucan are explored, and future research directions and application prospects are proposed, aiming to provide a theoretical basis for the further development and utilization of yeast β-glucan.

Lactic acid bacteria, as an important group of probiotics, often experience a marked decline in survival rate and activity during food processing due to exposure to extreme environmental conditions.The biofilm synthesized by the bacteria themselves serves as a key strategy for microorganisms to cope with environmental stress, achieve longterm colonization, and express functional traits.Moreover, biofilms play a vital role in enhancing host immunity and maintaining intestinal microbial balance.Consequently, this review summarizes the main factors influencing lactic acid bacterial biofilm formation and the underlying mechanisms.It highlights that different strains and environmental conditions lead to significant variations in biofilm quantity, structure, and function, demonstrating strong strain specificity and environmental dependence.The aim is to provide a theoretical basis for industrial fermentation of lactic acid bacteria and the development of probiotic formulations.

Food allergies are abnormal immune reactions triggered by specific food proteins and affect approximately 15% of children and 18% of adults globally.This has become a global public health concern.Therefore, establishing rapid and accurate testing methods for food allergens is of great significance in preventing and controlling allergic reactions.Current detection technologies generally rely on traditional antibodies, which have limitations such as low sensitivity, poor interference resistance, and are easily affected by food processing.Nanobodies (Nbs), which are variable region fragments of camelid heavy chain antibodies, have unique advantages, such as small molecular weight, strong stability, ease of genetic engineering modification, and low-cost production.It is particularly capable of recognizing hidden epitopes that are difficult for traditional antibodies to access, showing tremendous potential in allergen detection in complex food matrices and processed foods.This article focuses on the molecular characteristics and advantages of Nb, briefly discusses its application progress in the field of food allergen detection, points out the current challenges Nb faces in this field, and forecasts future development directions, providing a reference for the development of a new generation of precise detection of food allergens.

Foodborne pathogens and their biofilms pose a significant threat to public health.Nevertheless, traditional detection methods have limitations such as complex operation, low sensitivity, and long processing times.These limitations prevent timely and accurate detection of pathogenic bacteria, leading to potential food safety risks.Therefore, this summary reviews the application of biosensors constructed with metal nanomaterials for the rapid detection of foodborne pathogenic bacteria.Metal nanomaterials (such as gold, silver, and metal-organic frameworks) have high specific surface areas, unique optical and electrical properties, and catalytic activity.By enhancing signals and constructing composite sensing platforms, the performance of biosensors is optimized, significantly improving detection sensitivity and specificity.They can rapidly detect pathogenic bacteria such as Salmonella, Escherichia coli, and Staphylococcus aureus, as well as their biofilms.In this study, it focuses on analyzing the current advantages and limitations of various biosensor types modified with metallic nanoparticles, carbon-based nanomaterials, transition metals, metal nanoclusters, and composite nanomaterials, aiming to provide theoretical foundations and practical insights for advancing their real-world applications in scenarios such as food safety regulation.

Fermentation of medicinal and edible homologous resources plays a core role in improving the bioavailability of active ingredients, with its quality primarily relying on complex microbial metabolic networks and environmental interactions.However, traditional fermentation processes face bottlenecks such as "black box" operations and nonlinearity, which seriously restrict product consistency and industrialization.In recent years, utilizing artificial intelligence technology to elucidate fermentation mechanisms has become a research hotspot.This paper systematically reviews the application status of AI in the fermentation of medicinal and edible resources, constructs an intelligent control system covering “perception-modeling-decision,” expounds on key technologies such as multimodal sensing, machine learning modeling, and reinforcement learning, and summarizes its application effects in substrate-strain intelligent screening matching, dynamic process optimization, and metabolic mechanism analysis.Furthermore, it discusses the current limitations regarding data scarcity and model generalization, and proposes an interdisciplinary collaboration strategy of “AI + synthetic biology + process engineering,” aiming to provide theoretical support and technical references for the precision manufacturing and standardized production of medicinal and edible resources.

Postbiotics are defined as preparations of inanimate microorganisms and/or their cellular components that confer health benefit on the host.These valuable compounds are typically derived from probiotics through inactivation processes or are obtained from fermentation metabolites.As the functional mechanisms of probiotics are further elucidated, alongside breakthroughs in inactivation technologies and advancements in the isolation and characterization of active components, the probiotic industry is progressively transitioning from the "live-cell era" to the "component-driven era." Within this shift, postbiotics have emerged as a novel functional ingredient, establishing themselves as one of the fastest-growing and most promising frontiers in the probiotic sector.In recent years, significant attention has been directed toward postbiotics due to their stable biological activities and extensive application potential, leading to their critical roles across diverse sectors including food, consumer chemicals, pharmaceuticals, and agriculture.This article systematically reviews recent progress in postbiotic production technologies and the current landscape of product development, with the aim of providing valuable references and practical guidance for the industrial-scale manufacturing and application of postbiotics and related products.

Plant essential oils are often encapsulated within Pickering emulsions to address inherent challenges including poor water solubility, high volatility, and chemical instability.Leveraging their remarkable stability, controllable release kinetics, and enhanced environmental profile, Pickering emulsion-based delivery systems have found extensive application in food preservation.This review systematically addresses the stabilization mechanisms and key influencing factors of plant essential oil delivery systems based on Pickering emulsions, along with the types and selection criteria of food-grade particle stabilizers.It also covers emulsion preparation methods, characterization techniques, and performance evaluation in terms of stability, functionality, and food applicability.Emphasis is placed on the application effects of this system, employing forms such as active films, coating layers, and other innovative formats, in preserving various foods including fruits, vegetables, meat products, and aquatic products.The review aims to provide a theoretical reference for the development and promotion of plant essential oil-based Pickering emulsions in the field of green food preservation.

Zein has important application value in the fields of drug delivery, food nutrition and biomedicine.Although it has good biocompatibility and degradability, it still faces challenges in terms of preparation reproducibility, drug loading capacity and release characteristics, and it is urgent to improve its performance through functional modification strategies.This paper systematically reviews the latest research progress of zein-based gliadin nanocarriers, and discusses the innovation and optimization of preparation technology, surface functionalization modification strategies and their applications in drug delivery and food embedding.Through the comprehensive analysis and prospect of existing research, it is hoped that this paper will provide a theoretical basis and technical reference for the in-depth study and diversified application of zein nanocarriers.

Deoxynivalenol (DON) is a toxic trichothecene secondary metabolite produced by fungi such as Fusarium graminearum and Fusarium culmorum, which extensively contaminates cereals (e.g., wheat, corn) and their products.DON and its derivatives exhibit multiple toxicological effects, including cytotoxicity and immunotoxicity.Certain derivatives can be reversely converted to DON during digestion, thereby posing a potential threat to human health.The research progress regarding the reduction, migration, and transformation of DON and its derivatives during grain processing is expounded, and the detoxification effects of various processing technologies are thoroughly investigated, with the aim of providing theoretical support and technical references for the safe processing of cereals, process optimization, the development of precise toxin control technologies, and the high-quality development of the whole-grain industry.