Emulsified sausages are widely popular due to their rich nutrition and good flavor, but they have quality issues such as high fat and sodium content, and a tendency to lose moisture easily during cooking. In the study, KCl was substituted for NaCl at sodium reduction levels of 0%, 20%, and 30%. Additionally, yeast protein was used to replace fat in emulsified sausage at ratios of 10%, 20%, 30% and 40%. The texture, color, water distribution, sensory attributes, and volatile flavor compounds of sausages were then analyzed. Results indicated that elasticity, cohesiveness, and resilience of yeast protein emulsified sausages were highest at 10% fat substitution and no sodium reduction. Maximum hardness, chewability, and elasticity were achieved at 20% fat substitution and 20% sodium reduction. However, reducing sodium by 30% significantly decreased these texture parameters compared to the control. The water distribution results showed that under no sodium reduction and 20% sodium reduction conditions, the bound water content in yeast protein emulsified sausages was significantly higher than in the control. However, under 30% sodium reduction, free water content in yeast protein emulsified sausages was significantly higher than in the control. Electronic tongue analysis revealed that the addition of yeast protein enhanced umami and richness while reducing saltiness. In conclusion, the appropriate yeast protein substitution ratios were 10% under no sodium reduction and 20% under 20% sodium reduction. The textural and sensory qualities of yeast protein emulsified sausages with 30% sodium reduction were lower than those of the controls, suggesting a sodium substitution ratio below 30% for yeast protein emulsified sausages.

In order to improve the rehydration characteristics of instant dry rice noodles, the effects of adding pregelatinized glutinous rice starch (PGRS) on the gelatinization, pasting and rheological properties of rice flour and the structure, food quality and starch digestibility of the instant dry rice noodles made of the rice flour were investigated. The results showed that adding 2%~8% PGRS reduced the gelatinization onset temperature of the rice flour by about 2.9 ℃, increased the enthalpy by more than 24%, increased the pasting viscosity by more than 6%, and weakened or enhanced the elasticity of the paste gel. When the addition amount of PGRS was 4%, the rehydration time was shortened to 280 s, and the texture and sensory quality remained good. When the addition amount of PGRS was ≤6%, the digestion resistance of instant dry rice noodles was enhanced, and the content of resistant starch (RS) increased by more than 33%. Therefore, the addition of PGRS could improve the rehydration characteristics of instant dry rice noodles and increase its RS content. This study provided a reference for applying PGRS to improve the quality of rice products.

This study used tilapia myofibrillar proteins (MP) as the base material, corn oil as the oil phase, and incorporated corn starch (CS) to construct emulsion gels, aiming to investigate the effects of pregelatinized CS at varying temperatures (25, 40, 60, 80, and 100 ℃) on the microstructure, particle size, rheological properties, stability and 3D printing properties of the emulsion gels. The findings demonstrated that increasing the pregelatinization temperature of CS significantly enhanced both the storage modulus (G') and apparent viscosity of the emulsion gel. The most pronounced improvement was observed when the pregelatinization temperature of CS was 60 ℃ (CS60). Raman spectroscopy analysis indicated that no covalent interactions were formed between MP and pregelatinized CS. Gel strength analysis further revealed that hydrogen bonding and hydrophobic interactions were the dominant intermolecular forces stabilizing the emulsion gel. This suggested that the starch molecules released from pregelatinized CS could form a denser three-dimensional network with MP through these intermolecular interactions. In addition, the 3D printing results showed that higher CS pregelatinization temperatures improved the texture of the emulsion gel, with CS60 exhibiting the highest printing precision. Overall, this study elucidated the underlying mechanism whereby pregelatinized CS enhanced the properties of MP-based emulsion gels and provided a theoretical basis for optimizing MP gel performance and 3D printability through starch modification.

In order to promote the high-value utilization of walnut green husk and provide a theoretical basis for its application as emulsifiers, foaming agents, and antioxidants, this study employed electron beam irradiation (EBI) at various doses (0, 5, 10, 25, and 50 kGy) to pretreat walnut green husk. The structural characteristics, physicochemical properties, and functional activities of the alkali-extracted polysaccharides were analyzed and compared following treatment. The results demonstrated that, compared to untreated walnut green husk polysaccharides, those subjected to low-dose EBI (5 kGy) exhibited the highest molar ratio of xylose (16.31%), molecular weight (80.43±2.37 kDa), particle size (145.99±4.64 nm), and water/oil retention capacity (40.61 g/g, 83.08 g/g). Polysaccharides from walnut green husk treated with moderate doses (10 and 25 kGy) showed significantly enhanced uronic acid content (35.69%±0.14%, 36.02%±0.37%), exceptional thermal stability (melting points of 84.87 ℃ and 86.63 ℃), emulsion activity (emulsification index: 14.41 m²/g and 13.64 m²/g), and ABTS⁺/DPPH free radical scavenging capacities (scavenging rates of 77.00% and 85.47% at 10 kGy, respectively). High-dose EBI (50 kGy) treatment of walnut green husk polysaccharides resulted in the highest foaming ability (56.67%), though other functional activities were somewhat reduced. Considering the properties of walnut green husk polysaccharides, this study concludes that 10 kGy is the optimal irradiation dose.

This study aimed to explore the potential application of probiotics for the safe removal of zearalenone (ZEN) from feed by screening and validating the ZEN transformation capability of a soil-derived Bacillus subtilis strain 23830. Critical fermentation parameters were systematically optimized to maximize ZEN removal efficiency. The structural characterization and in vitro toxicity profile of biotransformation products were analyzed using ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS) and HepG2 cytotoxicity assays. The strain was further evaluated for practical application through fermentation trials on corn by-products. Key findings revealed that ZEN-transforming proteases were predominantly localized in the intracellular fraction. Under optimal transformation conditions (2% inoculum [1×10⁷ CFU/mL], 37 ℃, pH7.0, 12 h incubation), a ZEN removal rate of 60.47%±2.18% was achieved. Structural analysis identified zearalenone-14-sulfate (ZEN-14-Sulf) as the primary metabolite, which demonstrated significantly reduced cytotoxicity compared with the parent compound. In practical applications, the strain exhibited differential detoxification efficiencies across substrates: 15.67%±0.64% (corn germ meal), 19.22%±2.35% (corn gluten feed), 30.71%±0.79% (corn protein powder), and 45.44%±2.73% (corn slurry). The Bacillus subtilis strain 23830 characterized in this study represents a promising microbial candidate for feed detoxification, enabling both effective ZEN reduction and low-toxicity biotransformation. These findings advance the development of probiotic-based strategies for mycotoxin mitigation in agricultural systems.

To obtain lactic acid bacteria (LAB) with aroma-producing capabilities for application in mustard fermentation, traditional isolation and culturing methods were employed to screen presumptive LAB strains from fermented vegetables. Aroma-producing LAB were selected using sniffing test and diacetyl content analysis. Growth and fermentation characteristics of the strains were studied, and they were inoculated into mustard juice to analyze volatile aroma components. The results showed that: A total of 67 LAB strains were isolated, from which 5 aroma-producing strains were screened. Based on morphological, physiological, biochemical, and 16S rDNA molecular identification, strains LJ036, LJ065, QT038, and JC091 were identified as Lactiplantibacillus plantarum, while JC045 was identified as Weissella hellenica. LJ065 and QT038 exhibited stronger acid-producing capabilities. QT038 grew well at pH3.5, showed slightly higher salt tolerance, and demonstrated good temperature tolerance. LJ036 exhibited the strongest antibacterial effect against Staphylococcus aureus. LJ065 possessed the highest nitrite degradation ability, with a degradation rate of 94.45%. HS-SPME-GC-MS (headspace solid-phase microextraction gas chromatography-mass spectrometry) identified 52 volatile compounds. The fermented groups contained higher levels of alcohols, aldehydes, and ketones. Among them, the QT038, LJ065, and LJ036 fermentation groups showed higher acetoin contents of 4.27, 3.11, and 3.80 μg/mL, respectively. Cluster heatmap analysis revealed higher levels of volatile components such as (Z)-2-hexen-1-ol, damascenone, (Z)-3-hexen-1-ol, 2-ethylphenol, and linalyl acetate in QT038, LJ065, and LJ036 fermented mustard juice, imparting more intense floral, fruity, and herbaceous notes to the mustard greens. Comprehensive evaluation indicated that QT038, LJ065, and LJ036 possessed favorable fermentation and aroma-producing characteristics and showed promise as potential starter cultures for inoculated fermentation of mustard.

Objective: The aim of this work was to purify and identify the β-glucanase active protein from the fermentation supernatant of Bacillus velezensis 2-6 which originated from mangrove, and to investigate the enzymatic characteristics of the purified β-glucanase active protein. Methods: The ammonium sulfate precipitation method and DEAE-Sepharose Fast Flow ion-exchange chromatography were used to purify the β-glucanase active protein from the supernatant of Bacillus velezensis 2-6. LC-MS/MS analysis was used to identify the purified protein. The enzyme activity of β-glucanase active protein was analyzed using DNS method. Thin layer chromatography was used to detect the degradation level of β-glucanase active protein on laminarin. Filter paper method was used to analyze the antibacterial activity of β-glucanase active protein on pathogenic microorganisms. Results: A protein with a molecular weight of approximately 45 kDa was obtained from strain 2-6 fermentation supernatant by 80% ammonium sulfate precipitation and DEAE-Sepharose Fast Flow ion-exchange chromatography, and the β-glucanase activity of this protein reached 36956.5 U/mg. The purified protein was deduced as glucuronic acid xylanase by LC-MS/MS which consisted of 423 amino acids and named as GxylE-v26. The optimal enzyme reaction temperature of GxylE-v26 was 60 ℃ and the optimal pH was 4. Low concentration of Fe²⁺ (1 mmol/L) could promote the enzyme activity of GxylE-v26 while medium (10 mmol/L) and high (100 mmol/L) concentration of Fe²⁺, Ca²⁺, Mg²⁺ and Ba²⁺ could inhibit the enzyme activity of GxylE-v26. GxylE-v26 could hydrolyze laminarin and exhibit inhibitory effects on the growth of Staphylococcus aureus and Pantoea ananatis. The inhibition zone diameters of 1 mg/mL GxylE-v26 against S. aureus and P. ananatis were 1 cm and 1.1 cm, respectively. Conclusion: A β-glucanase active protein, named GxylE-v26, was purified and identified from the fermentation supernatant of Bacillus velezensis 2-6 which derived from mangrove. GxylE-v26 was an acid enzyme which could tolerate a certain degree of high temperature and possess antimicrobial activity against Staphylococcus aureus and Pantoea ananas.

To investigate the structural characteristics of water soluble polysaccharides in the pulp of Annona squamosa L. (WPAS) and their antibacterial effects against foodborne pathogens, WPAS was extracted using ultrasound assisted extraction, then purified. Its structures were characterized using ion chromatography, high-performance gel permeation chromatography, infrared spectroscopy, Congo red assay, X-ray diffraction, Zeta potential analysis, and scanning electron microscopy. The results indicated that WPAS was a neutral polysaccharide composed mainly of arabinose as the primary monosaccharide, with an average molecular weight of 14.99 kDa, an amorphous structure, a porous network morphology on the surface, and good stability in solution. In vitro antibacterial assays revealed that at a mass concentration of 20 mg/mL, the antibacterial zone diameters against Bacillus subtilis and Pseudomonas aeruginosa were 20.34±0.75 mm and 10.21±1.47 mm, respectively, and minimum inhibitory concentrations of 12.50 mg/mL and 17.50 mg/mL, respectively. Antibacterial efficacy against Bacillus subtilis and Pseudomonas aeruginosa was evaluated using cell-membrane permeability assays and adenosine triphosphatase (ATPase) activity measurements. The results showed that WPAS disrupted bacterial cell membrane integrity and significantly inhibited ATPase activity, thereby exerting significant antibacterial effects. In summary, WPAS demonstrates significant antibacterial activity against Bacillus subtilis and Pseudomonas aeruginosa. These findings provide a theoretical foundation for the application of Annona squamosa L. polysaccharides in food preservation and functional product development.

Hyaluronic acid (HA) is a high-value glycosaminoglycan that is extensively utilized in the food, pharmaceutical, and cosmetic industries. In this study, to establish greener and more cost-effective methods for HA production, Pichia pastoris was employed as a cell factory to evaluate the feasibility of synthesizing HA from methanol, a C1 substrate. Initially, an HA biosynthetic pathway was designed, which was subsequently incorporated into P. pastoriscells. The production of HA was quantified and confirmed using liquid chromatography and mass spectrometry, thereby verifying the successful establishment of an engineered cell factory. Using this system as a basis, with a view toward enhancing HA yield, hyaluronic acid synthases from different sources were screened. The results revealed that the hyaluronic acid synthase seHAS, derived from Streptococcus equi subsp. zooepidemicus, was characterized by the highest efficiency. Using this synthase, an HA titer of 941 mg/L with a molecular weight of approximately 1100 kDa was obtained under shake flask conditions. In addition, the efficacy of selected high-activity HA depolymerases was assessed, and both exogenous addition and co-expression approaches were employed to analyze potential bottlenecks in HA production. It was found that the depolymerase FhChAC was highly expressed in P. pastoris, and regardless of whether it was exogenously supplied or co-expressed, HA polysaccharides accumulated on the cell surface were efficiently released and degraded to oligosaccharides, thereby contributing to a significant increase in overall HA yield. Based on these optimization steps, a final shake flask fermentation yield of 5.6 g/L of unsaturated disaccharide-form HA oligosaccharides was obtained. The findings from this study are expected to provide important theoretical insights and technical guidance for the engineering of P. pastoris to produce HA from methanol.

In order to investigate the optimal extraction process and anti-inflammatory activity of white kidney bean polypeptides (WKBPs), this study employed white kidney bean protein as raw material and hydrolyzed white kidney bean protein by ultrasound-assisted enzymatic hydrolysis, utilizing the inhibition rate of bovine serum protein degeneration as the index. We identified the optimal extraction process with a single-factor combined response surface method and separated the prepared white kidney bean crude peptides with ultrafiltration tubes of different molecular weights. This study determined the anti-inflammatory activity of various components in vitro, detected the optimal components by liquid chromatography-mass spectrometry (LC-MS/MS), and examined the anti-inflammatory peptide segments by virtual screening and molecular docking techniques. The results indicated that the inhibition rate of WKBPs on bovine serum protein denaturation was 86.57% under the conditions of 166 W ultrasonic power, 18000 U/g enzyme addition, 128 min enzymatic hydrolysis time, and 46 ℃ enzymatic hydrolysis temperature. After ultrafiltration, the components with Mw<1 kDa revealed good anti-inflammatory activity (bovine serum protein denaturation inhibition, hyaluronidase inhibition, and NO inhibition), and the IC₅₀ values were 1.181, 9.244 and 10.887 mg/mL, respectively. We detected 3306 peptides by LC-MS/MS, of which 73% were peptide sequences ranging from 3 to 10. Virtual screening Vina score with type and induced nitric oxide synthase (inducible nitric oxide synthase, iNOS) binding energy minimum peptide sequence of 4 peptide FFFR, molecular docking visualization findings demonstrated that 4-peptide FFFR could bind to the active site of iNOS via hydrogen bonding and hydrophobic interaction, thus exerting inhibitory effects. This study serves as a reference for further research on the anti-inflammatory activity of WKBPs.