Pulsed electric field (PEF) processing promoted oxidation of charged residues of proteins, while its mechanism remained vague. In this study, polarization and oxidation of arginine (Arg) and glutamic acid (Glu) induced by PEF treatment (5-20 kV/cm for 4 h) was investigated through experimental characterization and density functional theory (DFT) computation. The results demonstrated that PEF treatment restrained the vibrational dipole moment of NH and CO within Arg and Glu side-chain, respectively. In Arg, H4-H6 signals shifted to a lower magnetic field with pronounced broadening, while C1, C4, C5, and C7 shifted to a higher magnetic field accompanied by the appearance of C=N-related resonances. In contrast, Glu's carbon skeleton shifted slightly to a lower magnetic field without structural conversion. Furthermore, residues were oxidatively degraded with electric field intensity extended, accompanied by impaired positive of Arg and negative charge of Glu. DFT revealed strong polarization of electron distribution within molecular framework, where 0.017 a.u. treatment partially detached the electrons from backbone of carbon-centered radicals. Thermodynamic calculations verified that electric-field alignment with molecular dipoles markedly reduced the energy barrier of β-cleavage, yielding distinct volatile profiles characterized by multi-site cleavage and N-heterocycle in Arg, and predominant aldehydes and acids in Glu. These findings clarified electric field-induced oxidation pathways and provided the theoretical guidance of PEF processing for improved quality stability.

This study systematically evaluated four tomato varieties for RSS fermentation. CT exhibited favorable physicochemical and antioxidant properties, with pronounced umami and sweetness. GC-IMS analysis identified CT as characterized by eugenol and ethyl (E)-2-hexenoate, which impart clove and oily notes, demonstrating its superior flavor and sensory potential. Dynamic analysis during CT fermentation (days 0-25) tracked the evolution of flavor precursors, key volatile organic compounds (VOCs), and microbial communities. GC-MS and GC-IMS identified 21 characteristic VOCs, grouped into three categories reflecting the transition from green, unripe notes to a mature, rounded flavor profile. Asp, Glu, His, and Arg were the main taste-active free amino acids, while citric and tartaric acids were the dominant organic acids. Bacterial communities were dominated by Pseudomonadota and Bacillota, and fungi by Monascus. Pearson correlation analysis revealed two functionally distinct clusters of core microorganisms in flavor formation. These findings elucidate the microbial and VOC dynamics during RSS fermentation.

This study investigates the regulatory effects of high magnetic fields (HMF) (0, 0.8, 1.2, 1.6 and 2.0 T) on the structural assembly and resultant biological performance of fish skin collagen peptide-cerium chelates (FSCP-Ce). At the molecular level, HMF treatment resulted in increased relative abundance of key Ce3+-coordinating amino acid in the HMF-FSCP-Ce, accompanied by conformational reorganization of the peptide structure. These changes significantly maximizing peptide-Ce3+ binding affinity with adsorption mass increasing from 165.61 f 12.34 to 829.40 f 21.45 ng/cm2. This process promoted a more compact and ordered chelate conformation (R-sheet content increased from 7.80% to 26.74%), ultimately forming stable, high-molecular-weight coordination architectures. This molecular optimization further induced supramolecular assembly of FSCP-Ce into compact nanospheres, characterized by increased particle size (from 221.81 f 11.72 to 370.33 f 23.49 nm), enhanced colloidal stability (Zeta-potential: from -5.6 f 0.6 to -21.3 f 1.8 mV), and improved solubility (from 65.85 f 2.17% to 88.75 f 1.59%). These structural enhancements contributed to enhanced in vitro stability, manifested as improved resistance to ionic displacement and superior gastrointestinal stability, elevating bioaccessibility from 37.15 f 4.87% to 61.72 f 4.1%. Furthermore, cellular bioavailability significantly rose from 57.59 f 2.52% to 75.28 f 2.32%, mediated by a distinct shift toward clathrin-dependent endocytosis alongside strengthened macropinocytosis. Conclusively, high magnetic fields provide an effective, non-thermal physical strategy to regulate the ordered and directional assembly of collagen peptide-cerium chelates. Therefore, HMF offers a promising green processing approach for developing a new generation of peptide-metal nutritional supplements.

Spices are essential contributors to the aroma of Chinese braised foods, but traditional industrial application methods, such as adding loose spices or using spice bags, face critical limitations. These include inefficient release of hydrophobic aroma compounds, poor flavor consistency across batches, and lack of precise control, ultimately compromising product quality and reproducibility. In this study, we developed a spice flavor extraction strategy, and the produced spice extract solution facilitates standardized and precisely dosed application, as well as quality control of related products in industrial applications. HS-GC-MS identified 46-67 volatile compounds per spice extract. Phenylpropanoids, monoterpenes, and sesquiterpenes were identified as the molecules most strongly correlated with solvent polarity. An 80% (v/v) ethanol solution was identified as the optimal extraction solvent, balancing flavor recovery and cost efficiency. After cooking as a Chinese braised soup, the spice extract concentrate exhibited significantly higher volatile abundance than traditional loose-spice and spice-bag methods, with a total volatile content 7.25-fold higher than that of the spice-bag sample. GC-MS, GC-IMS, and odor activity value combined analysis confirmed anethole, terpinen-4-ol, γ-terpinene, linalool, and D-limonene as key aroma-active compounds in the braised soup. Lastly, the braised soup was prepared by industrial braising with duck wings; the spices extraction group retained markedly higher total volatiles and showed lower flavor loss (36.2%) compared to loose-spice processing (91.2%). Electronic tongue analysis further demonstrated that the extraction method reduced astringency and after-astringency compared to traditional methods without increasing bitterness. These findings demonstrate that ethanol-assisted spice extraction could improve spice utilization and support standardized flavor regulation in braised food processing.

Iron ions (Fe 2+ and Fe 3+ ) are essential trace elements for the human body, and are often added to various foods, but their effects on protein glycation remain unclear. This study evaluated the differential influences of Fe 2+ and Fe 3+ on the glycation reaction of β -lactoglobulin ( β -Lg)-D-ribose system in terms of glycation degree, protein conformation and the distribution of modification sites. Free amino group contents and HPLC HCD MS/MS analyses indicated that both Fe 3+ and Fe 2+ could catalyze the glycation process and increase the glycated sites. The system contain Fe 2+ exhibited higher glycation degree and more glycation sites (8), and lesser glycation sites were identified in system contain Fe 3+ (5) and system without ferric ions (2). Additional sites (L1, K14, K135) were facilitated glycation by Fe 2+ , and most glycation sites showed higher degree of substitution per peptide (DSP) values when with Fe 2+ . In comparison with Fe 2+ , Fe 3+ caused more pronounced alterations on both secondary and tertiary protein structure, promoted the β -Lg unfolding, and changed the protein structure to a more unordered form. In conclusion, Fe 2+ at a specified concentration was a better choice to promote glycation reaction while maintain the protein structure. This study provide a theoretical basis for protein glycation modification with iron ions at different valence states participated.

The functional performances are encoded by protein structures, and modified structure-based strategies for customizing food proteins have major implications for the food industry. The glycation reaction that typically occurs between food components is a promising strategy for protein modification due to its mild reaction conditions and natural occurrence during processing. However, the complexity and dynamic nature of glycation reactions hinder precise control, and there is a large imbalance between abundant structural data and function information. Artificial intelligence (AI), with its capacity for large-scale data integration and predictive modeling, offers transformative potential for elucidating glycation-structure-function relationships. This review therefore aims to (1) summarize advances in analytical strategies for glycated proteins, highlighting techniques for site localization, conformational analysis, and multi-source data mining; (2) elucidate how glycation-induced structural modifications alter protein functional performance, providing mechanistic insights into physicochemical properties and biological activities; and (3) discuss emerging AI-driven approaches, including deep learning and inverse design, for predicting and optimizing glycation patterns. These insights provide a systematic framework to accelerate rational development of functional proteins and promote innovative applications in the food industry.

Combining physical modification with enzymolysis reduces ovalbumin (OVA) allergenicity by disrupting conformational and linear epitopes. Yet hydrolytic-resistant, epitope-containing peptides can retain IgE-binding sites, limiting further decreases in allergenicity. We observed an inverse relation between peptide molecular weight and allergenicity. Accordingly, size-exclusion chromatography separated native OVA and hydrolysates from microwave-treated OVA (OVA-N-E, OVA-M-20-E) into three fractions (F1-F3) by molecular size to probe link molecular weight, epitope distribution, and allergenicity. Liquid chromatography demonstrated that longer-retention-time components had lower molecular weights, and in OVA-M-E-F3, components below 1 kDa accounted for as much as 97.89%. Mass spectrometry and cellular degranulation experiments revealed that as molecular weight decreased, the proportion of short peptides increased, while the proportion of peptides containing intact IgE-binding epitopes gradually decreased, leading to reduced allergenicity. Additionally, OVA's amino acid sequences (Y125-T136, A141-N154, F188-V200, V243-E248, G301-S308, I323-A332) were protease-resistant and displayed a structural profile dominated by beta-folds.

This study aimed to identify allergenic epitopes of tropomyosin by characterizing peptide interactions with major histocompatibility complex class II (pMHC-II) using semiempirical quantum computation (Geometry, Frequency, Noncovalent, extended Tight Binding, GFN2-xTB), Molecular Mechanics Poisson Boltzmann surface area (MMPBSA) and GFN-FF, and verified their correlation with experimental allergenicity. The results clarified that nine species-conserved peptides were identified, six of which were validated as antigenic epitopes. Interactive interface within pMHC-II complexes identified critical residue pairs and structural motifs for antigen presentation mechanism. By capturing electronic and dispersion effects, GFN2-xTB performed better than MMPBSA and GFN-FF in charged-ligand system, exhibiting a Pearson correlation of -0.74 between ΔGbind and IgE inhibition. Furthermore, partial least squares regression using interactive isosurface areas in GFN2-xTB revealed a correlation between MHC-II' anchors and IgE binding (R2 = 0.77). Conclusively, molecular dynamics combined with GFN2-xTB can elucidate epitope peptides' distribution, specific anchors, and correlation between ΔGbind and IgE.

Ce3+ has increasingly recognized in the food science for its antioxidant and osteogenic properties. This study aims to investigate the physicochemical characteristics and osteogenic potential of the osteogenic peptide-cerium (III) chelate (GEYL-Ce). The application of a high magnetic field during the chelation process significantly enhanced the cerium loading capacity in GEYL-Ce. The analysis of UV-vis, FT-IR and SEM demonstrated that Ce3+ forms stable coordination bonds with the functional groups (-NH2, -COO- and -OH) in GEYL. GEYL-Ce exhibited superior antioxidant capacity, while reducing ROS in osteoblast from 78.32 % to 32.62 %. Critically, GEYL-Ce restored osteoblast function under oxidative stress, ALP activity (from 113.33 to 229.57 U/gprot) and mineralization capacity (from 0.32 to 0.84). Mechanistically, it synergistically activated BMP-2/Smads and Wnt/(3-Catenin pathways. This study may provide new insights into the development of GEYL-Ce as a novel nutritional supplement for bone health.

The effects of superheated steam (SS) on functional properties of ovalbumin (OVA) and the underlying molecular mechanism were investigated. SS treatment significantly enhanced OVA's emulsifying capacity, antioxidant activity, and digestive properties compared to conventional heating methods. The results showed that SS treatment exposed hydrophobic regions of OVA and induced oxidation and phosphorylation. LC-Orbitrap-MS analysis revealed that phosphoryl group transfer from S68 and S344 enhanced emulsifying properties, while M35 oxidation and Y42 phosphorylation facilitated the exposure of antioxidant peptide sequences 36-40. Furthermore, peptidomic analysis demonstrated that SS promoted the generation of small-molecule peptides, identifying 53 unique peptides and 8 specific cleavage sites. Integration of site-specific modification mapping with peptide profiling revealed that modification sites (S164, M222, S257, S353) enhanced pepsin accessibility by exposing specific digestion sites. These findings establish SS treatment as a promising approach for enhancing protein functional properties, offering significant potential in food processing applications.

Due to health reasons of polyglycerol polyricinoleate (PGPR), there has been a growing interest in reducing it. To address this, this study developed the PGPR/Protein (whey, pea, and chickpea protein isolates) emulsifier combinations. The effects of these combinations on the preparation, structure, physicochemical and in vitro digestive properties of W/O/W microcapsules were evaluated. The FTIR and XRD analyses revealed hydrogen bonding interactions between the protein and PGPR (or bioactive compounds), which may contribute to the enhanced encapsulation efficiency (EE) and stability of microcapsules. PGPR/pea protein isolate (PP) microcapsules exhibited more uniform size, better rehydration, and higher EE than other microcapsules. PP combinations prolonged shelf-life of microcapsules by 1.35 to 1.73-fold, as predicted by oxidation kinetic models. Furthermore, PP microcapsules improved the bioavailability of crocin (≥ 11.08 %) and quercetin (≥ 8.47 %). Overall, this study hoped to provide a promising strategy for preparing W/O/W microcapsules with low PGPR content.

The mechanism of H2O2 combined pulsed electric field (PEF) treatment stimulating oxidation and decreasing allergenicity of parvalbumin of grass carp and tropomyosin of king prawn was clarified. Compared to H2O2 treatment alone, the IgG-binding capacity of parvalbumin and tropomyosin significantly decreased by 21.87 % and 81.18 % after H2O2 combined PEF treatment, while the IgE binding capacity reduced by 63.42 % and 76.91 %. center dot OH caused by electrochemical reaction triggered oxidative degradation of protein and disrupted their allergenic epitopes, which resulted in the structural unfolding, hydrophobic quenching and prevented the recognition by related antibody. Molecular dynamics showed that H2O2 combined PEF treatment promoted center dot OH interaction with surface residues than alone H2O2 treatment and PEF treatment, where the H2O2 treatment and H2O2 combined PEF treatment caused significant structural alterations of tropomyosin, which greatly converted alpha-helix to random coil. Furthermore, density functional theory calculation revealed that hydrogen abstraction at C alpha rendered more stable intermediates where the spin density of the unpaired electron was lower, while alcohol formed by addition of center dot OH to the side chains was pretty stable but their phenyl and imidazolyl states were more preferred than the saturated side-chains-containing ones.

The mechanism of PEF treatment (5-20 kV/cm for 0.5-2 h) changing spatial conformation and enhancing allergenicity of parvalbumin of grass carp was clarified, and molecular dynamics simulations (MDS) was utilized to explore hot-spot residues and epitopes of parvalbumin-IgE complex. The phenomenon revealed that the IgG and IgE binding capacity of parvalbumin maximally enhanced by 37.24 % and 27.63 % respectively, but subsequently decreased after 20 kV/cm exposure for 1 h. Atomic force microscope showed that the particle morphology of PEF-treated parvalbumin became more regular and homogeneous, with dissociation of aggregates due to decreased hydrophobic interaction. Furthermore, 5-20 kV/cm treatments promoted conformation unfolded and de-spiralization, rendering it easy for target antibodies to interact with related epitopes. MDS showed that the critical epitopes between parvalbumin and IgE were phenylalanine58, glutamate60-61, aspartate91, aspartate93-glycine96 and glutamate102 with ΔG < -1 kcal/mol, and hot-spot residues were phenylalanine, glutamate and aspartate with ΔΔG > 1 kcal/mol.

We present a method for precisely localizing IgE-linear epitopes by adsorption of peptides containing IgE-linear epitopes onto magnetic beads. Optimal enzymatic hydrolysis conditions (55 degrees C, 40 min) were determined to disrupt the OVA structure, facilitating specific adsorption of peptides containing IgE-linear epitopes onto magnetic beads. Using Liquid-mass spectrometry, we identified fourteen peptides with IgE-linear epitopes, among which epitopes 3 (T91-F99), 4 (L124-F134), 6 (V160-D167), 9 (V243-E248), and 13 (S317-K322) were found to be high-frequency IgE-linear epitopes. Additionally, epitopes 1 (V41-Q52), 3 (T91-F99), 8 (Y212-A220), 11 (N292-V296), and 13 (S317-K322) were identified as previously unreported IgE-linear epitopes. Through solidphase peptide synthesis, indirect competitive ELISA and molecular docking. The results showed that the above five peptides were mainly bound to MHC-II through hydrogen bonding. Among them, epitope 3 has the strongest affinity for MHC-II. In conclusion, magnetic beads adsorption of peptides containing IgE-linear epitopes was a novel method for the precise localization of IgE-linear epitopes. This technique was facile to execute and enables rapid and accurate identification of IgE-antigen binding sites.

BackgroundRobot-assisted feeding systems aim to promote independence for individuals with motor impairments. Despite significant technological progress, widespread adoption remains limited due to challenges related to adaptability, safety, and cost.ObjectiveThis review investigates recent advancements in robot-assisted feeding, highlights key technical and usability challenges, and outlines future directions to improve system adaptability, autonomy, and cost-effectiveness.MethodsA systematic literature search was conducted for peer-reviewed articles published in the past decade. The analysis focuses on critical domains including hardware architecture, human-robot interaction (HRI) modalities, and control strategies.ResultsAdvances in artificial intelligence (AI) and HRI have enhanced system autonomy and user adaptability. Nevertheless, unresolved issues persist in handling diverse food types, achieving real-time responsiveness, and minimizing system costs. Emerging solutions-such as adaptive learning, Artificial Intelligence of Things (AIoT) integration, and modular design-offer promising pathways to overcome these barriers and support scalable deployment in real-world care settings.

Purified fish skin collagen peptide (FSCP) was used to chelate Ce3+ to prepare peptide‑cerium chelate (FSCP-Ce) to improve their in vitro stability and cellular uptake for oral delivery. The study revealed that the primary chelation sites between FSCP and Ce3+ were located on the side chains of tryptophan, aspartic acid, glutamic acid, lysine and histidine (cerium-chelating capacity 75.32 mg/g). FSCP-Ce showed good in vitro stability, gastrointestinal digestive stability. Furthermore, this study demonstrated that the 1.32 mg/mL FSCP-Ce significantly increase cell viability (FSCP-Ce: 98.77 ± 1.56 % VS CeCl3: 64.21 ± 1.92 %) and cerium absorption (FSCP-Ce: 57.59 ± 2.51 % VS CeCl3: 27.29 ± 2.02 %) compared to 1 mg/mL CeCl3. The endocytosis pathway results indicate that the main cellular transport pathways for FSCP-Ce are giant cytosol drinking and vesicle protein-dependent endocytosis, which adds multiple uptake pathways compared to CeCl3. This research establishes a basis for investigating peptide‑cerium chelate as a new type of nutritional supplement, aiming to lower cerium toxicity while enhancing its bioavailability.

β-lactoglobulin (β-Lg), the major whey protein containing nine lysine residues, serves as an ideal model for studying protein glycation and thermal processing safety in dairy products. This study systematically compared three different high-temperature treatment methods, namely superheated steam (SS), hot air (HA), and oil bath (OB), to investigate their effects on the spatial conformation and glycation product formation of proteins in the β-Lg-glucose system. The results show that compared with OB and HA, SS has a lower degree of glycation, lower consumption of free amino groups, and less unfolding of the protein’s three-dimensional structure. It leads to a lower proportion of α-helix transformation into β-sheet and random coil in the protein. SS resulted in the least browning and produced less 5-hydroxymethylfurfural, pentosidine, fluorescent advanced glycation end products, and melanogenin, yet produced the highest amount of Carboxymethyllysine. Mass spectrometry analysis shows that lysine residues were the primary glycation sites. Therefore, this work provides molecular-level insights into how different heating techniques modulate protein glycation and structural stability, supporting the potential of superheated steam as a gentler alternative to control glycation for β-Lg in food thermal processing.

Heat treatments induce protein-reducing sugar glycation reactions easily, leading to protein structural transformations and advanced glycation end products generation. In this study, effects of four heat conduction modes (air, contact, vapour and liquid-conduction) on the spatial conformation and glycation products of gliadin-glucose system were evaluated. The results showed that gliadin tertiary structure expanded and exposed more hydrophobic sites in vapour-conduction, resulting in more glycation sites. Conversely, air-conduction promoted the protein folded, causing a lighter glycation degree and lower glyoxal, methylglyoxal, acrylamide, 5-hydroxymethylfurfural and carboxymethyl lysine contents (following vapour-conduction > contact-conduction > liquid-conduction > air-conduction). The above phenomena were attributed to the different water content in the different conduction modes. Furthermore, the glycation sites identified in vapour-conduction and contact-conduction were approximately two-fold of that in air-conduction. Conclusively, gliadin-glucose systems subjected to air-conduction showed less glycated intensity and hazardous products.

The effect of electric field intensities (EFIs, 5-20 kV/cm) and treatment times (0.5-2 h) on allergenicity and spatial conformation of prawn tropomyosin was evaluated. The results demonstrated that the IgG and IgE binding capacity of tropomyosin maximally increased by 24.34 % and 29.16 % respectively, followed by a subsequent decrease after 20 kV/cm treatment for 1 h. Interestingly, 5-10 kV/cm treatments significantly decreased the alpha-helix content (P < 0.05) and fluorescence intensity, while 20 kV/cm treatment promoted extensive spiralization, resulting in a tightly packed structure. The increased flexibility further exposed the hydrolysis sites and strengthened the gastrointestinal digestibility of tropomyosin. Additionally, molecular dynamic simulation indicated that extended EFIs increased structural flexibility and depolymerized the tropomyosin dimers through destroying intermolecular hydrogen bonds (formed within arginine and glutamate), which allowed tropomyosin to be easily recognized by IgG/IgE. Whereas, decrease of solvent-accessibility surface area (SASA), hydrophobic surface area induced conformation folded and caused epitopes masked.