To investigate the impact of ultrasound-assisted curing on the quality attributes and protein oxidation of stir-fried chicken dices and its underlying mechanism, chicken dices were cured under ultrasound conditions (120 W, 40 kHz) for varying durations (0, 30, 60, 90, 120, 150 min). Changes in physicochemical properties, texture characteristics, sensory quality, oxidation indicators, and protein digestibility were systematically analyzed. The results demonstrated that ultrasound-assisted curing significantly increased the moisture content of stir-fried chicken dices (P<0.05) and improved color parameters, with the 90-min treatment group exhibiting optimal L^* and a^* values (60.83 and 7.44, respectively). Texture profile analysis revealed that ultrasound treatment significantly reduced hardness (from 3474.99 g to 2673.61 g) and chewiness, effectively enhancing tenderness. Protein oxidation analysis indicated that ultrasound accelerated the oxidation process of myofibrillar protein, characterized by a decrease in total sulfhydryl group content and an increase in carbonyl group content. However, SDS-PAGE results confirmed no significant protein degradation occurred. With the extension of ultrasound time, the in vitro digestibility of protein significantly increased from 40.3% in the control group to 86.4% in the 150-minute group, while the digestibility of the 90-minute treatment group was 72.3%, and the overall sensory score significantly improved. When the ultrasound treatment duration exceeded 90 min, excessive protein oxidation occurred, leading to quality deterioration. Comprehensive analysis identified 90 min as the optimal ultrasound-assisted curing time. Under these conditions, stir-fried chicken dices exhibited the best texture characteristics, sensory quality, and nutritional value.

This study systematically investigated the effects of ⁶⁰Co-γ-ray irradiation on the structural characteristics and processing properties of gluten proteins. Gluten protein samples were irradiated at doses of 0, 1, 3, 5, 7, and 9 kGy. The investigation assessed the free sulfhydryl groups, disulfide bonds, secondary structure, molecular weight distribution, color attributes, water-holding capacity, emulsifying properties, taste profiles of gluten protein, and the pasting characteristics of the wheat starch-gluten protein reconstituted system under varying irradiation conditions. The results demonstrated that after γ-ray irradiation treatment, the free sulfhydryl group content in wheat gluten protein consistently exceeded that of the control group. Meanwhile, the disulfide bond content decreased gradually from 488.71 μmol·g⁻¹ to 259.21 μmol·g⁻¹. The protein secondary structure exhibited a conversion from α-helix to β-sheet. SDS-PAGE analysis indicated partial degradation or aggregation of proteins. Irradiation improved certain processing properties of wheat gluten protein. Notably, at an irradiation dose of 7 kGy, the L^* value of color raised by 14.61%, water-holding capacity increased by 0.09 g/g, and emulsion activity and stability were enhanced by 1.84-fold and 5.48-fold, respectively. Irradiation exhibited relatively limited effects on the taste of gluten protein and the pasting properties of wheat starch-gluten protein reconstituted systems. The peak viscosity, final viscosity, and breakdown value of reconstituted flours decreased only at the highest irradiation dose of 9 kGy (P<0.05). This study provides a theoretical foundation for the application of irradiation in flour product processing and gluten protein modification.

The present study investigated the effects of resistant corn starch (RCS) heat-treated at various temperatures (25, 40, 60, 80, and 100 ℃) on tilapia myofibrillar protein (MP) emulsion gel viscoelastic properties, particle size distribution, microstructure, centrifugal stability, Raman spectroscopy and three-dimensional (3D) printing characteristics. The results showed that the RCS heat-treatment temperature significantly modulated the hydrophobic interactions, thereby affecting the emulsion gel rheology and structural stability. When the RCS heat treatment temperature was 40 ℃, RCS swelled moderately, and the emulsion gel exhibited optimal performance, demonstrating pseudoplastic flow behavior, high elasticity, and a uniform particle size distribution. Apparent viscosity, storage modulus (G'), thixotropic recovery rate, and particle size uniformity increased significantly, thus enhancing the gel network structure and stability. This formulation exhibited excellent 3D printing extrudability and self-supporting ability, maintaining its structural integrity even after astaxanthin loading. Raman spectroscopy revealed that hydrophobic forces primarily governed gel network formation without covalent bond involvement. When the RCS heat treatment temperature exceeds 60 ℃, the the linear starch in the RCS leaches out, causing decrease in apparent viscosity and shear stress.Collectively, this study elucidated the mechanism through which heat-treatment temperature regulated RCS to influence RCS-MP emulsion gel stability. The findings showed that 40 ℃ was the optimal temperature for enhancing rheology and 3D printing performance, thereby providing a crucial theoretical basis for developing high-precision, personalized 3D printing food-grade inks and expanding RCS applications in functional foods.

Taking gray Sufu inoculated with Mucor UV-M2 as the research object, the changes of volatile metabolites, microorganisms and their correlation during fermentation of grag Sufu were explored. In this study, the quality of the fermentation process was comprehensively evaluated using physicochemical indexes and sensory assessment methods. The results confirmed that the fermentation process reached an optimal state after 40 days. Non-targeted volatile metabolomics analysis revealed significant variations in metabolites at different fermentation stages. Based on the odor threshold, 18 compounds with an odor activity value (OAV)>1 were evaluated. Among them, 11 compounds contributed to the aroma profile, including esters, aldehydes, and ketones, while 7 compounds were associated with unpleasant odors, mainly sulfur-containing compounds. Microbiological analysis demonstrated that the diversity of fungi and bacteria decreased significantly as the fermentation progressed. Through Spearman correlation analysis, it was found that the bacteria Tetragenococcus and Halanaerobium exhibited positive correlations with most volatile compounds with OAV>1, whereas Acinetobacter showed negative correlations with these compounds. Among fungi, Mortierella, Aspergillus, Malassezia, Botrytis, Penicillium, and Sagenomella were positively correlated with most of the compounds, while Actinomucor and Candida showed negative correlations. Furthermore, the results of redundancy analysis (RDA) indicated that, among bacteria, Weissella and other genera were positively correlated with salt content. In the fungal community, amino-acid nitrogen was positively correlated with Mortierella, salt content was positively correlated with Actinomucor, and pH was positively correlated with Kodamaea. These findings suggest that the quality indexes of gray Sufu are positively associated with the core microbial flora. Overall, the above results indicate a significant correlation between the aroma characteristics and the microbial community at different stages during the fermentation of gray Sufu. This study provides valuable references for enhancing the flavor quality of gray Sufu through microbial regulation techniques.

To explore the effect of berberine hydrochloride on the proliferation and differentiation of chicken myoblasts. In this study, the effects of berberine hydrochloride on cell proliferation and differentiation were detected by CCK-8 assay, EdU staining and Desmin immunofluorescence staining. The gene expression levels of myogenic factor 5 (MYF5) and myogenic differentiation 1 (MYOD) were determined by real-time quantitative PCR (RT-qPCR). The effects of berberine hydrochloride on the gene expression profiles of chicken myoblasts were also investigated by RNA sequencing analysis. The results showed that berberine hydrochloride treatment significantly promoted the proliferation of chicken myoblasts while inhibiting the expression of MYOD (P<0.01) and MYF5 (P<0.05). Desmin staining showed slightly weaker fluorescence signals in the cytoplasm of the experimental group than that of the control group, indicating that berberine hydrochloride inhibited the differentiation of chicken myoblasts to a certain extent. In addition, Gene Ontology enrichment analysis (GO) showed that the differential genes were mainly enriched in extracellular space and matrix, cell adhesion, and cell migration regulation after berberine hydrochloride treatment; Kyoto Encyclopedia of Genes and Genomes enrichment analysis (KEGG) showed that the differential genes were mainly enriched in tyrosine metabolism, TGF-β signaling pathway, MAPK signaling pathway and cell adhesion molecule-related signaling pathway. The RT-qPCR results showed that in the TGF-β pathway, the expression of Inhibitor of DNA Binding 1 (ID1) and Paired-like Homeodomain Transcription Factor 2 (PITX2) was upregulated, while Follistatin (FST) was downregulated. In the MAPK pathway, the pro-proliferative genes Insulin-like Growth Factor 2 (IGF2), Fibroblast Growth Factor 7 (FGF7), FBJ Murine Osteosarcoma Viral Oncogene Homolog (FOS), Fms-related Tyrosine Kinase 1 (FLT1), and MAPK-activated Protein Kinase 3 (MAPKAPK3) were all upregulated, whereas the calcium channel gene Calcium Voltage-gated Channel Subunit Alpha1 E (CACNA1E) was downregulated. These findings suggested that berberine hydrochloride might synergistically regulate the proliferation-differentiation balance of myoblasts through the interaction between the TGF-β and MAPK signaling pathways. In this study, we found that berberine hydrochloride promoted the proliferation of chicken myoblasts and analyzed the molecular mechanism and provided theoretical support for the efficient culture of chicken myoblasts in vitro.

This study aimed to screen lactic acid bacteria (LAB) with high exopolysaccharide (EPS)-producing capacity from traditional yak yogurt in Western Sichuan, and to characterize the structure and functional properties of the EPS. Among 185 LAB strains isolated, Limosilactobacillus fermentum 197 was identified as a high EPS producer. The fermentation medium was optimized through single-factor experiments, and the EPS was purified using DEAE-52 and CL-6B column chromatography. The purified fraction EPS1 was structurally characterized by Fourier-transform infrared spectroscopy, gel permeation chromatography, and nuclear magnetic resonance, and its bioactivities were evaluated in vitro. The results showed that the optimal carbon and nitrogen sources for EPS production were maltose and soybean peptone, both at 40 g/L. After optimization, the EPS yield reached 1699.83±34.31 mg/L, representing a 5-fold increase compared to the original yield. The purified EPS1, with a yield of 15.07%, had a molecular weight of 2.11×10⁵ Da and was composed of rhamnose, arabinose, galactose, glucose, and mannose. It contained both α- and β-glycosidic bonds, exhibited a triple-helix structure, and displayed a flaky porous morphology under microscopy. In vitro assays demonstrated that EPS1 at 10 mg/mL exhibited scavenging rates against ABTS⁺, DPPH, and hydroxyl radicals of 57.07%, 46.54%, and 49.68%, respectively, and an α-amylase inhibition rate of 51.46%. This study reveals the relationship between the structure of EPS1 and its antioxidant and hypoglycemic activities, providing a theoretical basis for developing functional dairy products using LAB-derived EPS and offering new insights into the utilization of lactic acid bacteria resources from plateau pastoral areas.

This study aimed to screen lactic acid bacteria (LAB) starters with high exopolysaccharides (EPS) production and to analyze their metabolic mechanisms. By assessing the EPS content in fermented skim milk co-cultured with nine laboratory-isolated EPS-producing LAB strains and commercial strains, the optimal starter (designated as the SW group) was identified as a composite of the laboratory-isolated Lactobacillus pentosus strain 15 and commercial strains. The EPS content and viscosity of skim milk fermented by the SW group were significantly (P<0.05) higher than those observed in the control group (S group). Through the integration of physicochemical analysis and LC-MS-based untargeted metabolomics, a total of 67 differential metabolites were identified, comprising 40 upregulated and 27 downregulated metabolites. Metabolic analysis indicated activation of the arginine biosynthesis pathway, as demonstrated by the upregulation of arginine and its precursor N-acetylglutamate-5-semialdehyde (NAGSA), alongside the downregulation of ornithine. Concurrently, the essential amino acid L-leucine was significantly upregulated. Organic acids, including 2-hydroxyhexanoic acid and hydrocinnamic acid, were found to modulate acidity, while the accumulation of benzoic acid contributed positively to shelf life extension. Furthermore, the upregulation of EPS synthesis precursors, specifically UDP-glucose and glucuronic acid, indicated that EPS synthesis predominantly involved glycosidic bond linkages among UDP-glucose, UDP-glucuronic acid, and GDP-mannose. Pathway enrichment analysis demonstrated that the cofactor biosynthesis pathway was the primary driver of the metabolic flux of EPS, with phenylalanine metabolism supplying essential nutrients and arginine biosynthesis facilitating the accumulation of functional components. Collectively, this study elucidated that the SW group enhanced nutritional value, antibacterial efficacy, and EPS production through multi-pathway metabolic regulation, thereby improving product texture and nutritional fortification. These findings offer a theoretical foundation for optimizing the quality of fermented foods.

Tomato grey mould, caused by Botrytis cinerea, is a severely damaging global disease. This study isolated a strain of antagonistic bacteria with strong inhibitory effects against the important plant pathogen Botrytis cinerea from healthy branches and leaves of Camellia sinensis in Yunnan's Gaoligong Mountain. The morphological and molecular biological identification results indicated that the antagonistic strain was Bacillus subtilis, which was designated as DB2203A. The fermentation conditions of strain DB2203A were optimized through single-factor and orthogonal experiments, and the antibacterial activity of the fermentation broth was determined along with a preliminary exploration of the antibacterial substances under these conditions. This study isolated and screened seven strains with strong antagonistic effects against pathogenic fungi from leaf and branch tissues. Among them, strain DB2203A exhibited the most significant inhibitory effect against B. cinerea, with its sterile fermentation broth achieving an inhibition rate of 74.77% against the pathogen. The optimal medium for the strain DB2203A was LB medium, with the best fermentation conditions being an inoculation volume of 6%, a filling volume of 50%, an initial pH of 7.0, and a fermentation time of 72 h. The research results also showed that the antifungal activity of the 40 times diluted fermentation broth against B. cinerea was 59.25%. Moreover, the lipopeptide substances in the fermentation broth could inhibit the growth of the mycelium of B. cinerea. The strain B. subtilis DB2203A and its lipopeptide metabolites exhibit promising potential for the green control of tomato gray mold, providing a theoretical foundation and microbial resources for the development of microbial products.

This study aimed to investigate the effects of different heat treatment methods (atmospheric pressure cooking, high-pressure cooking, atmospheric pressure steaming, high-pressure steaming, and microwave heating) and time (2 to 10 minutes) on the quality of Antarctic krill. The results showed that under the same heating time, the heat treatment loss rate of atmospheric pressure steaming was the lowest, and it was significantly lower than the other four methods within 6 minutes (P<0.05). Microwave heating performed best in terms of crude protein, crude fat, astaxanthin content, L^*, b^* values, and sensory scores, while atmospheric pressure cooking had the highest a^* value. As the heating time increased, the heat treatment loss rate of all five methods rose, and the differences were significant within 6 minutes (P<0.05), the contents of crude protein and crude fat decreased, and there was no significant difference within 6 minutes and 8 minutes or more (P>0.05), but the difference between 6 and 8 minutes was significant (P<0.05), the astaxanthin content and sensory scores first increased and then decreased, reaching the highest at 6 minutes, and then significantly decreased after 6 minutes (P<0.05), L^* and b^* values increased, while a^* value decreased, and the color differences were significant between 6 and 8 minutes (P<0.05). Through a comprehensive analysis of the overall impact of heat treatment methods and time on various quality indicators of krill, it was concluded that microwave heating was preferred within 2 to 6 minutes, followed by high-pressure steaming; both microwave heating and high-pressure steaming were optimal within 6 to 8 minutes; and microwave heating and atmospheric pressure steaming performed better at 8 minutes or more. This study provides a theoretical basis for the processing of Antarctic krill, which is helpful for optimizing the processing flow, improving product quality, and promoting industrial development.

To explore the effects of different pretreatment methods on the structure and physicochemical properties of soluble dietary fiber (SDF) from millet bran and to achieve its high-value utilization. This study used millet bran as the raw material and SDF yield as the indicator. Single-factor and orthogonal experiments were employed to determine the optimal pretreatment conditions for the different pretreatment methods (ultrasound, superfine grinding, and ultrasound-superfine grinding combination). The effects of different treatment methods on the structure and physicochemical characteristics of millet bran SDF were analyzed by measuring indicators such as monosaccharide composition, molecular weight distribution, infrared spectra, internal particle structure, micro-morphology, thermogravimetric, water holding capacity, oil holding capacity, swelling capacity, and solubility. The results showed that under the conditions of grinding particle size of 800 mesh, solid-liquid ratio of 1:40 (g/mL), ultrasonic power of 330 W, and ultrasonic time of 50 min, the highest SDF yield of millet bran reached 20.44%±0.17%, representing a 2.68-fold increase in yield. Compared with conventional grinding, ultrasound, and superfine grinding, their combination altered the relative content of monosaccharide components in millet bran SDF. The combination of both methods increased the proportion of high molecular weight components to 45.42%, forming a loose and porous structure on the crystal surface, and had the most obvious effect on reducing its orderliness and thermal stability. Meanwhile, analysis of physicochemical characteristics indicated that the ultrasound-superfine grinding combination significantly improved the water-holding capacity, oil-holding capacity, swelling capacity, and solubility of millet bran SDF (P<0.05). Therefore, the combined treatment of ultrasound and superfine grinding enhances the physicochemical characteristics by improving its structure, thereby improving the processing performance and increasing the potential utilization value of millet bran SDF.