Search Results (142)

Pangasius (Pangasianodon hypophthalmus) minced muscle with 1 and 2% salt was treated with different high-pressure processing and thermal methods, including conventional heat-induced gels (HIGs), high-pressure processing (HPP) prior to cooking (PC), HPP prior to setting (PS), and setting prior to HPP (SP), to evaluate for their effects on the selected physicochemical properties. The results showed that the PC treatment produced gels with a significantly higher gel strength (496.72–501.26 N·mm), hardness (9.62–10.14 N), and water-holding capacity (87.79–89.74%) compared to the HIG treatment, which showed a gel strength of 391.24 N·mm, a hardness of 7.36 N, and a water-holding capacity of 77.98%. PC gels also exhibited the typical microstructure of pressure-induced gels, with a denser and homogeneous microstructure compared to the rough and loosely connected structure of HIGs. In contrast, SP treatment exhibited the poorest gel quality in all parameters, with gel strength ranging from 319.79 to 338.34 N·mm, hardness from 5.87 to 6.31 N, and WHC from 71.91 to 73.72%. Meanwhile, the PS treatment showed a comparable gel quality to HIGs. SDS-PAGE analysis revealed protein degradation and aggregation in HPP-treated samples, with a decrease in the intensity of myosin heavy chains and actin bands. Fourier-transform infrared spectroscopy (FTIR) analysis showed minor shifts in protein secondary structures, with the PC treatment showing a significant increase in α-helices (28.09 ± 0.51%) and a decrease in random coil content (6.69 ± 0.92%) compared to α-helices (23.61 ± 0.83) and random coil structures (9.47 ± 1.48) in HIGs (p < 0.05). Only the PC treatment resulted in a significant reduction in total plate count (TPC) (1.51–1.58 log CFU/g) compared to 2.33 ± 0.33 log CFU/g in the HIG treatment. These findings suggest that HPP should be applied prior to thermal treatments (cooking or setting) to achieve an improved gel quality in reduced-salt pangasius products. Full article

This study investigated the effects of curdlan (CUR) with different helical conformations on the gelling behavior and mechanisms of heat-induced soy protein isolate (SPI) gels. The results demonstrated that CUR significantly improved the functional properties of SPI gels, including water-holding capacity (0.31–5.06% increase), gel strength (7.01–240.51% enhancement), textural properties, viscoelasticity, and thermal stability. The incorporation of CUR facilitated the unfolding and cross-linking of SPI molecules, leading to enhanced network formation. Notably, SPI composite gels containing CUR with an ordered triple-helix bundled structure exhibited superior gelling performance compared to other helical conformations, characterized by a more compact and uniform microstructure. This improvement was attributed to stronger hydrogen bonding interactions between the triple-helix CUR and SPI molecules. Furthermore, the entanglement of triple-helix CUR with SPI promoted the formation of a denser and more homogeneous interpenetrating polymer network. These findings indicate that triple-helix CUR is highly effective in optimizing the gelling characteristics of heat-induced SPI gels. This study provides new insights into the structure–function relationship of CUR in SPI-based gel systems, offering potential strategies for designing high-performance protein–polysaccharide composite gels. The findings establish a theoretical foundation for applications in the food industry. Full article

Egg protein gels have relatively poor water-holding capacity, hardness, and freeze–thaw properties. Jujube juicing residue dietary fiber (JJRDF) is available, but it is rarely used in the food industry because of its poor hydration properties. Versions of JJRDF modified via cellulase and xylanase hydrolysis separately coupled with carboxymethylation (JJRDF-CXHC), phosphate crosslinking (JJRDF-CXHPC), and acetylation (JJRDF-CXHA) were prepared, and their effects on heat-induced and alkaline-induced egg protein gels (HA-EPGs) were studied. Smaller particle sizes and higher solubility, viscosity, expansion volume, and ability to retain water were observed in JJRDF-CXHC, JJRDF-CXHPC, and JJRDF-CXHA compared to JJRDF (p < 0.05). JJRDF-CXHC showed the highest viscosity (18.46 cP) and expansion volume (10.40 mL/g). Higher random coil and β-sheet contents resulted in an increase in pH, adhesiveness, hardness, and chewiness, and a decrease in the water-losing rate in freeze–thaw cycles, and gastric digestion was observed in the HA-EPGs as a consequence of adding JJRDF, JJRDF-CXHC, JJRDF-CXHPC, and JJRDF-CXHA at 3–5 g/100 g. Moreover, JJRDF-CXHC and JJRDF-CXHPC were better at improving the textural quality of the unmodified HA-EPG compared to JJRDF-CXHA and JJRDF (p < 0.05). Therefore, to improve egg protein gel quality, JJRDF modified with cellulase and xylanase hydrolysis separately coupled with carboxymethylation and crosslinking is a good choice. However, the functionalities of these modified JJRDFs should be studied. Full article

The enhancement of gel properties in chicken myofibrillar proteins (MPs) is a crucial objective in meat processing. In this experiment, we systematically investigated the effects of lentinan (LNT) on MP gel formation ability and three-dimensional network structure features through multi-scale structural characterization and molecular interactions analysis and elucidated the molecular pathways of their molecular actions in regulating gel properties. The addition of LNT (0–2%, w/v) significantly enhanced the water-holding capacity (WHC), textural, and rheological properties of LNT-MPs. As the concentration of LNT increased, the hydrophobic and electrostatic interactions became more pronounced. Conversely, the contribution from disulfide bonds exhibited an inverse relationship, with hydrogen bonds demonstrating the least impact. Subsequently, the α-helix content decreased from 23.75% to 22.64%, and the β-fold content increased from 28.03% to 29.22%, suggesting that the protein aggregates reorganized to form larger aggregates, which contributed to forming a more stable network structure of gels. This investigation establishes LNT’s capacity to modify the gelation mechanisms of MPs. These outcomes offer crucial insights for implementing fungal polysaccharides in processed meat product development. Full article

This study developed iron-oxide-functionalized carbon xerogels for enhanced arsenic adsorption to mitigate global water contamination. The composites were synthesized by integrating magnetite nanoparticles (15–20 nm) into a resorcinol–formaldehyde matrix via sol–gel polycondensation, followed by controlled pyrolysis. Key parameters—magnetite/resorcinol ratios (0.03–0.07), carbonization conditions (temperature, heating rate, duration), and H₂O₂-induced surface modification—were optimized to maximize adsorption performance. Characterization (SEM/EDX, XRD, FTIR, BET, TEM) confirmed uniform magnetite dispersion (~5 wt%) and revealed that pyrolysis at 850 °C enhanced porosity (378.8 m²/g surface area) and refined surface chemistry. Adsorption kinetics followed Elovich (R² = 0.9396) and Power Function (R² = 0.9443) models, indicating chemisorption dominance. Response Surface Methodology optimized desorption parameters using a Central Composite Design with three factors and two center points with repetition. A kinetic study of As(V) desorption from carbon xerogels was conducted, yielding optimal conditions: 1.0 M KOH, 160 rpm agitation, and 90 min contact time. The adsorbent retained >88% regeneration efficiency over four cycles, demonstrating robust reusability. Synergistic effects of magnetite incorporation, tailored pyrolysis, and H₂O₂ modification significantly improved arsenic selectivity and capacity in complex matrices, while enabling magnetic recovery. Full article

This study investigated the effects of high-pressure processing (HPP) on selected physicochemical properties of pangasius gels at reduced salt concentrations. Minced pangasius muscle was treated at different HPP conditions (300–500 MPa/10 °C/10 min) with 1% or 2% added salt, then cooking (90 °C/30 min) and compared to heat-induced gels (HIGs) with 2% added salt and cooking (90 °C/30 min). The results showed that HPP significantly improved the texture, whiteness, and water-holding capacity of gels added salt 2% as compared to HIGs. At a reduced salt concentration of 1%, the gel texture, whiteness, and water-holding capacity of pangasius gels are similar to HIGs. SDS-PAGE showed a reduction in myosin band intensity of both SDS-soluble and sarcoplasmic proteins with pressure treatment. Sarcoplasmic actin protein was undetectable in all treatments. Fourier transform infrared spectroscopy (FTIR) analysis revealed higher α-helix content in HPP-treated samples, while SEM images confirmed the formation of a denser, more uniform gel network, particularly at 2% salt. These findings suggested that HPP improved the quality of gel with 2% salt added, while producing gels with similar quality compared to HIGs at reduced salt concentration. Full article

This study investigated the effects of ultrasound treatment on the physicochemical properties and thermal stability of durian starch. Durian starch samples were subjected to ultrasound at 20 kHz and 500 W for 2 min. The treatment significantly increased the starch extraction yield by 14.55% compared to untreated starch. Scanning electron microscopy analysis revealed that ultrasound treatment induced physical modifications in the starch granules, including the formation of cracks and pores, which likely contributed to the enhanced extraction efficiency and influenced the starch’s gelation behavior. Thermal analysis, including differential scanning calorimetry and thermogravimetric analysis, demonstrated that ultrasound-treated starch exhibited higher thermal stability compared to native starch. The thermogravimetric analysis results indicated a lower weight loss at high temperatures (70.39% for ultrasound-treated starch versus 79.55% for native starch at 596 °C). The heat flow during thermal decomposition was reduced in ultrasound-treated starch, suggesting that the treatment induced structural modifications that strengthened the gel matrix and improved resistance to thermal degradation. Additionally, ultrasound treatment enhanced the functional properties of durian starch, including swelling power, solubility, and water absorption capacity, which are critical for hydrogel formation and food-grade gel applications. These findings highlight the potential of ultrasound-treated durian starch for advanced applications in food hydrogels, biodegradable films, and gel-based delivery systems. Full article

The bay scallop (Argopecten irradians) adductor is an attractive raw material for the production of surimi-like products. The gelling properties of raw materials directly affect the quality of surimi-like products. To assess the potential of processing frozen bay scallop adductors into surimi-like products, the effects of short-term freezing treatment on the endogenous transglutaminase (TGase) activity, myofibrillar protein (MP) structure and gelling properties of bay scallop adductors were investigated during 14 days of frozen storage (−18 °C). The results showed that TGase activity in adductor muscles increased significantly during the first 7 days. After 7–14 days, the carbonyl and sulfhydryl contents of the MPs notably changed (increased then decreased). The β-turn content of the MPs increased, indicating stretching and flexibility. Surface hydrophobicity, fluorescence intensity and sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) analysis demonstrated changes in the tertiary structure of the MPs. Compared with gels from fresh samples, gels from scallop adductors frozen for 1 day presented significantly better texture characteristics (breaking force, gel strength, hardness, springiness, cohesiveness, chewiness) and higher water-holding capacity (p < 0.05). However, these properties significantly decreased on the 7th and 14th days (p < 0.05). Microstructural analysis revealed a more compact gel network from 1-day-frozen adductor muscles. These changes in TGase activity and MP structure are key factors influencing the gelling properties of frozen bay scallop adductors. This study provides new insights for improving gel properties during the frozen storage of bay scallop adductors. Full article

Phenolic acids have a positive effect on the processing quality of myofibrillar protein (MP) gels. However, in this study, the addition of ferulic acid (FA) did not have a positive effect on MP gels. To address this issue, we performed the addition and observed the effects on the structure of MP gels by both surface coating and internal cross-linking: addition of FA alone, addition of α-cyclodextrin (CD) to encapsulate FA (MP-FA/CD), and addition of Fe(III) to form a metal–phenolic network structure (Fe @MP-FA) and a metal–cyclodextrin–phenolic acid structure (Fe@MP-FA /CD). It was found that both Fe @MP-FA formed by surface coating and internal cross-linking were able to improve the textural properties of MP gels, including hardness, elasticity, chewability, adhesion, etc. FA effectively promoted the conversion of some of the non-fluidizable water to the bound water morphology, and the addition of Fe(III) effectively enhanced this trend. In particular, the composite network structure formed by Fe@MP-FA/CD more significantly promoted the conversion to bound water and improved the water retention of the gel. Hydrophobic interactions and hydrogen bonding in non-covalent bonding as well as disulfide bonding in covalent bonding were always the main factors promoting the formation of gels from MP after different additions. Meanwhile, different gel treatments lead to changes in the structure of different proteins. Internal cross-linking with the addition of FA promotes protein oxidation, whereas CD reduces the occurrence of oxidation and promotes a homogeneous gel structure. Surface coating with the addition of FA/CD resulted in a reduction in pores in the MP gels and a denser gel structure. However, the addition of internal cross-linking resulted in a gel with a loose and rough network structure. In this study, we compared the common methods of gel enhancement, with the objective of providing a reference for the improvement in the gel texture of meat products. Full article

To enhance and stabilise the edible quality of coated tofu, this study explored the changes in the microstructure and intermolecular forces of coated tofu gel and sol under different heat treatments. It elucidated the phase transformation mechanism of coated tofu gel and sol under heat treatment. The results showed that the protein structure unfolded, the fluorescence intensity decreased, and the protein solubility, surface hydrophobicity, and free sulfhydryl group content increased as the coated tofu gel transformed to sol. Disulfide bonding and hydrophobic interactions were the primary intermolecular forces in the heat-induced gel–sol transition. FTIR showed that the content of β-sheets decreased significantly during gel–sol transformation, while the content of β-turns, α-helices and random coils increased significantly. Most remained relatively stable during the gel–sol transformation process, with only the A and B subunits of the 11S protein decreasing slightly. Their reduction became significant when the temperature reached 200 °C. Additionally, the high-temperature heat treatment promoted the gel–sol transition of the coated tofu, with its cross-section gradually transforming from a porous network structure to a more uniform and smooth texture during heat treatment process. The findings of this study provide a theoretical basis for improving the quality of coated tofu by optimising heat treatment parameters, laying the groundwork for future advancements in the development of pre-heat-treated coated tofu. Full article

Currently, there is an increasing demand for advanced materials that can address the needs of tissue engineering and have the potential for use in treatments targeting tumor cells, such as black bioactive materials in photothermal therapy. Thus, 3D fibrous scaffolds of black 45S5 bioactive glass were produced using the air-heated solution blow spinning (A-HSBS) technique, with polyvinylpyrrolidone (PVP) serving as a spinning aid and an oxygen vacancy-inducing agent. Glass powder with the same composition was synthesized via the sol-gel route for comparison. The samples were characterized using thermogravimetric analysis, X-ray diffraction, FTIR spectroscopy, and scanning electron microscopy, along with in vitro tests using simulated body fluid (SBF), phosphate-buffered saline (PBS), and TRIS solution. The results showed that PVP enhanced oxygen vacancy formation and stabilized the scaffolds at 600 °C. Doping with Zn and Mg ions reduced crystallization while significantly increasing the fiber diameters. Scaffolds doped with Zn exhibited lower degradation rates, delayed apatite formation, and hindered ionic release. Conversely, Mg ions facilitated greater interaction with the medium and rapid apatite formation, completely covering the fibers. The scaffolds showed no cytotoxicity in the MTT assay at concentrations of up to 200 µg/mL for HaCat cells and 0.8 mg/mL for L929 cells. This study demonstrated the effectiveness of using PVP in the production of black bioactive glass scaffolds, highlighting their potential for bone regeneration. Full article

This study investigates the effect of microencapsulated temperature rise inhibitors (TRIs) on the hydration temperature evolution and crack resistance of medium-sized concrete structures. Unlike mass concrete, medium-sized concrete elements such as beams, slabs, and columns pose unique challenges in temperature control due to their moderate volume, limited heat dissipation, and susceptibility to thermal stress-induced cracking. To address this issue, concrete mixtures with TRI dosages of 0%, 0.05%, 0.1%, and 0.15% were evaluated using a sealed foam box method, allowing for precise monitoring of hydration temperature development under insulated conditions. The results indicate that TRIs effectively suppress peak hydration temperature and delays its occurrence, with higher TRI dosages leading to more pronounced effects. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses confirm that the hydration suppression is attributed to a controlled-release mechanism, where TRIs gradually dissolve, forming a hydration barrier on cement particles. This slows down calcium hydroxide (CH) crystallization, alters C-S-H gel evolution, and reduces early age heat accumulation, mitigating thermal cracking risks. Furthermore, mechanical property tests reveal that, while early age compressive and tensile strength decrease with TRI addition, long-term strength recovery is achieved at optimum TRI dosages. This study identifies 0.1% TRI as the most effective dosage, striking a balance between hydration heat reduction and long-term mechanical performance. These findings provide a scientific basis for optimizing TRI dosages in medium-sized concrete applications, offering a practical solution for thermal cracking prevention. Full article

Stimuli-responsive materials, particularly supramolecular hydrogels, exhibit a dynamic adaptability to external factors such as pH and ultrasound. Among these, phenylalanine (Phe)-derived hydrogels are promising due to their biocompatibility, biodegradability, and tunable properties, making them ideal for biomedical applications. This study explores the effects of pH and ultrasound on the gelation properties of N-substituted Phe derivatives, with a primary focus on the role of ultrasound in optimizing the gelation process. A series of N-substituted Phe derivatives were synthesized via reductive amination and hydrolysis. Hydrogel formation was possible with two of these compounds, namely G1 and G2, using the following two methods: heating–cooling (H–C) and heating–ultrasound–cooling (H–US–C). The critical gelation concentration (CGC), gelation kinetics, thermal stability (T_gel), and viscoelastic properties were assessed. Morphological and cytotoxicity analyses were performed to confirm the suitability of these gels for biomedical applications. Both G1 and G2 derivatives demonstrated enhanced gelation under the H–US–C protocol compared to H–C, with notable reductions in CGC (up to 47%) and gelation time (by over 90%). Ultrasound-induced gels led to an improved network density and stability, while maintaining thermal reversibility and mechanical properties comparable to those of hydrogels formed without ultrasound. Cytotoxicity studies confirmed a high biocompatibility, with cell viability rates above 95% across the tested concentrations. Given the similar rheological and morphological properties of the hydrogels regardless of the preparation method, drug release experiments were performed with representative gel samples and demonstrated the efficient encapsulation and controlled release of 5-fluorouracil and methotrexate from the hydrogels, supporting their potential as pH-responsive drug delivery platforms. This study highlights the role of ultrasound as a powerful tool for accelerating and optimizing the gelation process of supramolecular hydrogels, which is particularly relevant for applications requiring rapid gel formation. The developed Phe-based hydrogels also demonstrate promising characteristics as drug delivery systems. Full article

Curdlan’s application is constrained by high gelation concentration, poor water solubility, and incompatibility with other polysaccharides. To address these limitations, this study investigated the effects of different concentrations (0.05–0.3%) of non-ionic polysaccharides (pullulan (PL), locust bean gum (LBG), guar gum (GG), and konjac gum (KGM)) on the heat-induced gelling properties of curdlan. PL with no branch showed 0.3% enhanced gel hardness. LBG with a small amount of galactose residue and KGM with an acetyl group had similar effects on hardness, while GG with a large amount of galactose residue slightly weakened the mixed gel. The rheological results showed that PL had little effect on curdlan, and LBG and KGM had a positive effect on curdlan unfolding, but 0.3% GG was significantly antagonistic to curdlan. The above results implied that non-ionic polysaccharides without side chains interacted weakly with the curdlan and hardly changed the properties of curdlan. Curdlan unfolding and stable suspension were favored if the structure contained galactose or acetyl side chains that interacted with curdlan through hydrogen bonding. These results suggested an effective way to modify curdlan by strengthening the interaction of curdlan with others and weakening the hydrogen bonding of curdlan to broaden its application in food colloids. Full article

Due to its poor hydration properties, oil palm kernel expeller dietary fiber (OPKEDF) is rarely used in the food industry, especially in hydrogels, despite its advantages of high availability and low cost. To address this situation, the effects of enzymolysis combined with hydroxypropylation or crosslinking on the structure and hydration properties of OPKEDF were investigated, and the impact of these modified OPKEDFs on the properties of egg white protein gel (EWPG) was studied. Enzymolysis combined with hydroxypropylation or phosphate crosslinking improved the soluble fiber content (5.25–7.79 g/100 g), water-retention and expansion abilities of OPKEDF (p < 0.05). The addition of unmodified OPKEDF or modified OPKEDF increased the random coil content of EWPG and increased the density of its microstructure. Moreover, enzymolysis combined with hydroxypropylation or crosslinking enhanced the effect of OPKEDF on the properties of EWPG, including improvements in its water-retention ability, pH, hardness (from 97.96 to 195.00 g), chewiness (from 78.65 to 147.39 g), and gumminess (from 84.63 to 152.27) and a reduction in its transparency (p < 0.05). Additionally, OPKEDF and enzymolysis and hydroxypropylated OPKEDF increased the resilience (0.297 to 0.359), but OPKEDF treated via enzymolysis and crosslinking reduced it. Therefore, OPKEDF modified by means of enzymolysis in combination with hydroxypropylation or crosslinking improved the gel properties of EWPG. However, further work is required to determine the effects of these modifications on the nutritional profile, scalability, and economic feasibility of OPKEDF and egg white gel. Full article