Properties Of Gels Research Articles

Properties of Rennet Gels from Retentate Produced by Cold Microfiltration of Heat-Treated and Microfiltered Skim Milk.

This study investigated the production of rennet gels from β-casein-depleted retentates obtained through cold microfiltration (MF) of skim milk (SM) that was treated beforehand to ensure microbial safety. The treatments included thermization (65 °C, 20 s), pasteurization (72 °C, 15 s), and microfiltration (50 °C; 1.4 μm pore size). The reduction in β-casein content was 0.98, 0.51 and 0.90%, respectively. All treatments resulted in the partial aggregation of serum proteins, which were slightly concentrated in the retentates obtained post cold MF process. This aggregation, along with concentration effect, likely inhibited β-casein dissociation from casein micelles and permeation, particularly in pasteurized milk. Renneting and coagulation properties of the retentates were comparable to those of the respective SM samples, with no significant differences in syneresis, water-holding capacity, or protein hydration. Notably, the retentate from thermized SM, which showed the best performance with the highest β-casein reduction (0.98%), demonstrated shorter coagulation time compared to retentate from pasteurized milk or the corresponding unfiltered SM. Textural analysis revealed greater firmness, cohesiveness, and viscosity of retentate-based rennet gels compared to gels made from unfiltered SM, attributed to protein concentration during cold MF. Overall, this study successfully produced rennet gels from cold MF retentates without compromising their physicochemical properties.

Bioprinted High-Cell-Density Laminar Scaffolds Stimulate Extracellular Matrix Production in Osteochondral Co-Cultures.

Many tissues have a laminar structure, but there are limited technologies for establishing laminar co-cultures for in vitro testing. Here, we demonstrate that collagen-alginate-fibrin (CAF) hydrogel scaffolds produced using the reactive jet impingement bioprinting technique can produce osteochondral laminar co-cultures with well-defined interfaces between cell types and high cell densities to support cell-cell interaction across the interfaces. The influence of cell density and the presence of the two cell types on the production of extracellular matrix (ECM) and the emergent mechanical properties of gels is investigated using IHC, ELISA, gel mass, and the compression modulus. The results indicate that high-cell-density cultures and co-cultures with these specific cell types produce greater levels of ECM and a more biomimetic in vitro culture than low-cell-density cultures. In laminar scaffolds produced using TC28a2 chondrocytes and SaoS-2 osteoblasts, both cell density and the presence of the two cell types enhance ECM production and the mechanical properties of the cultures, presenting a promising approach for the production of more biomimetic in vitro models.

Inhibition of Biogenic Amines in Fermented Tilapia Surimi by Collaborative Fermentation of Latilactobacillus sakei and Pediococcus acidilactici.

Fermentation is an effective method for ameliorating the gelation properties of freshwater fish surimi, but the formation of biogenic amines (BAs) during fermentation should also be controlled. In this study, the BAs in fermented tilapia surimi were inhibited by the collaborative fermentation of Latilactobacillus sakei and Pediococcus acidilactici, followed by the revelation of the BA inhibition mechanism. Most of the BAs, and the total BA, as well as their precusor free amino acids (FAAs), were significantly reduced, while the umami FAAs, including glutamic acid and aspartic acid, were significantly enhanced after cooperative fermentation with starters. The high-throughput sequencing found that the spoilage microorganisms such as Acinetobacter, Micrococcus, and Streptococcus as well as Pediococcus were significantly inhibited, while Latilactobacillus rapidly became the dominant genus after cooperative fermentation, suggesting the better environment adaptability of L. sakei than P. acidilactici. The group-dimension correlation analysis suggested that Lactiplantibacillus had the greatest influence on the decrease in BAss. The quick acidification of starters, especially L. sakei, could inhibit the growth and metabolism of spoilage microorganisms to reduce BAs. L. sakei and P. acidilactici can be developed as the special starters to control the BA production in the fermented tilapia surimi through collaborative fermentation.

Prediction of 3D printability and rheological properties of different pineapple gel formulations based on LF-NMR

In this study, a pineapple-starch-xanthan gum system was prepared using fresh pineapple juice, maize starch, and xanthan gum (XG). The feasibility of using low-field nuclear magnetic resonance (LF-NMR) to predict pineapple gels' rheological properties and printability was evaluated. Results indicated that as maize starch and XG increased, the gel transformed from unable to support printed models to a stable shape, eventually becoming too viscous for printing. Principal component analysis and Fisher discriminant analysis classified the gels into four categories based on their rheological properties, aligning with the actual printing results. Pearson correlation analysis showed a strong correlation between the LF-NMR parameters and the rheological properties of gels. The partial least squares (PLS) and back-propagation artificial neural network (BP-ANN) models constructed using the LF-NMR parameters can effectively predict the rheological properties of pineapple gels. Therefore, LF-NMR is a valuable, non-destructive method for quickly assessing pineapple gels' 3D printing suitability.

Effect of β-sitosterol and oil phase on gel properties, microstructure and sensory characteristics of pea protein/carrageenan emulsion gels as solid fat substitutes

In this study, pea protein isolate (PPI)/κ-carrageenan (CG) emulsion gels were formulated with various oil phases (sunflower seed oil, SFO; cocoa butter, CB; palm stearin/SFO, PST/SFO) and β-sitosterol (β-Sit) concentrations (0%, 5%, 10%, 15%, 20% w/w) to mimic the textural and melting properties of animal solid fat. The potential application of these emulsion gels as solid fat substitutes in reduced-fat sausage was also evaluated. Confocal laser scanning microscopy and polarized light microscope images revealed an increase in mean droplet diameter and crystal size of the emulsion gels at higher β-Sit concentration. Compared to CB and SFO samples, PST/SFO emulsion gels exhibited more numerous, smaller crystals and a more homogeneous protein network structure. Texture analysis showed the hardness of the three emulsion gels progressively increased and the springiness reduced with rising β-Sit concentrations. Among the oil phases, PST/SFO emulsion gels with 20% β-Sit exhibited texture properties and melting behavior most akin to pork back fat (PBF). Scanning electron microscopy showed that the replacement of PBF with PST/SFO emulsion gels at higher substitution ratios resulted in a rougher structure with increased amounts of gel particle aggregates and voids of sausages although the texture property and gel strength were enhanced. Overall, sensory perception revealed that sausages with ≤75% fat replacement remained highly acceptable. This study offers a novel approach to developing animal fat substitutes with adjustable texture and crystallization characteristics based on PPI/CG emulsion gels.

Investigating the Sway of Marine Brown Seaweed Gel as Natural Polymer in Properties of Concrete

In the present study, the effects of the fresh properties as slump, consistency and setting time and hardened concrete's characteristics such as compressive, split tensile and flexural strength for various ages, the brown seaweed (Sargassum wightii) gel was added to cement throughout differing proportions (1, 2, 3, 4 and 5%) by the mass of concrete. Durability and thermal tests such as water absorption, sorptivity, RCPT, acid attack and thermal conductivity also determined at various ages. Micro structural properties of seaweed gel were found out by SEM, FTIR and XRD analysis. Test results show that seaweed gel act as retarding admixture in cement up to 5% of addition. For instance, 5% alginate collections as a percentage of concrete mass showed a comparable compressive strength of about 42MPa. The use of seaweed gel improved the thermal characteristics of concrete by reducing its thermal conductivity roughly 50% for a 5% addition. The seaweed gels up to 5% addition in concrete will significantly improve the fresh-state properties of concrete without affecting its hardened properties. The future is completely dependent on eco-friendly materials; hence the use of natural organic additives to improve the strength and durability of cement concrete would be the better option for sustainability.

Effect of 3D printing accuracy by wheat starch gel combined with canola oil

This study investigated the impact of canola oil (CO) on wheat starch (WS) in 3D printing, focusing on intermolecular interactions and gel characteristics. 3D printing performance, microstructure, rheology, texture, proton distribution, thermal properties, molecular structures, and crystal structure were used to analyze the properties of starch gels. The results showed that adding CO improved the similarity between printed products and their models, and facilitated smoother extrusion by enhancing the cohesiveness and adhesiveness of the WS-CO complex. Moreover, adding >6 % CO to the starch gels destabilized the 3D-printed structure, causing the top layer to collapse, which affected the aesthetics and printing accuracy. The WS-4%CO complex demonstrated superior printing performance and enhanced accuracy. FTIR (Fourier Transform Infrared) and NMR (Nuclear Magnetic Resonance) results indicated that the interaction between WS and CO involved non-covalent interactions, primarily hydrophobic interactions. SEM (scanning electron microscope) results further revealed the molecular structure, CO hindered the interaction between amylose and amylopectin, disrupting the ordered structure and increasing lamellar formation, thereby affecting the stability of the 3D printing structure. This experiment provides valuable insights for enriching the nutrition and improving the accuracy of 3D-printed food.

Mechanism of Toona sinensis seed polyphenols inhibiting oxidation and modifying physicochemical and gel properties of pork myofibrillar protein under oxidation system

This research aimed to elucidate how Toona sinensis seed polyphenols (TSSs) inhibited pork myofibrillar protein (MP) oxidation and modified physicochemical and gel properties in the Fenton oxidation system. Our result displayed that TSSs had a lower carbonyl (from 1.38 to 0.59 nmol/mg) and dityrosine contents (from 47.22 to 25.07), and higher free amino content (from 386.99 to 485.00 nmol/mg), followed by ellagic acid (EA) and quercetin-3-O-rhamnoside (QC). Meanwhile, the incorporation of phenolic compounds changed secondary and tertiary structure of proteins and then increased solubility and absolute value of zeta potential, as well as decreased turbidity and average particle size. Molecular docking indicated that MP interacted with EA primarily via hydrogen bonds and hydrophobic interaction, and with QC mostly through hydrogen bonds and electrostatic interaction. Otherwise, the incorporation of EA promoted MP gel to form a honeycomb-like microstructure after oxidation. Therefore, TSSs, EA, and QC could significantly inhibit MP oxidation as well as modify its physicochemical properties, but only EA enhanced its gel properties after oxidation. The results could be useful to improve the comprehensive utilization of plant by-products and provide theoretical references for the role of TSSs in the improvement of meat products.

Insight of soy protein isolate to decrease the gel properties corn starch based binary system: Rheological and structural investigation

Dysphagia has become a growing concern for elderly individuals, and starch-based gel foods is expected to become one of the foods easy to swallow. This study investigated the effects of soy protein isolate (SPI) on the sol-gel behavior, rheological, structural and gel properties of corn starch (CS). SPI raised the gelatinization temperature but reduced enthalpy values, inhibiting the gelatinization of CS. There was a reduction of rheological properties in CS-SPI system, involving apparent viscosity, modulus, and shear structural recovery properties, while SPI increased the Tan δ, creep-recovery, and thixotropic properties. Structural analysis demonstrated that SPI introduction altered the lamellar structure, increased the relative crystallinity, and decreased the hydrogen bond strength and order degree in CS-SPI gels, forming a weaker gel network. As a result, the texture profiles such as hardness, gumminess, and chewiness were decreased from 308.60 g to 64.98 g, 285.44 g–50.62 g, and 279.66 g–50.15 g, respectively, whereas the gel strength of CS-SPI gel decreased from 123.91 g to 45.78 g. This study provided foundations for the production of gel food suitable for swallowing.

Development and characterisation of a novel bigel based on pea protein hydrogel and rice bran wax oleogel: Enhancement of rheological properties and freeze-thaw stability

In this study, a novel pea protein (PP)-based bigel was developed, featuring a high internal phase emulsion. The impact of gelling agent concentration on the gel properties and freeze-thaw stability of the bigel was investigated. The bigel was comprised of two distinct gel phases: an aqueous-phase gel with a covalent network formed by PP and transglutaminase (TGase), and an oil-phase gel with a crystal network structure of rice bran wax (RBW). Microstructural analysis revealed a bi-continuous network structure in the bigel, with network density increasing as TGase and RBW concentrations rose. Rheological analysis showed that storage modulus (G′), apparent viscosity, and structural recovery of the bigel increased with higher TGase and RBW concentrations. Temperature scanning experiments confirmed that the bigel maintained its elastic solid behavior even at elevated temperatures. Optimal sensory properties and low coefficient of friction were achieved at 0.4 % TGase and 7 % RBW concentrations. Additionally, the bigel exhibited notable freeze-thaw stability at TGase and RBW concentrations exceeding 0.2 % and 5 %, respectively. These findings highlight the excellent gelation properties and stability of the PP-RBW-based bigel, suggesting its potential as a fat substitute in the food industry.

Effect of β-sitosterol+γ-oryzanol-based oleogels on protein conformation and gel properties of Nemiperus virgatus surimi.

The impact of β-sitosterol+γ-oryzanol-based oleogels or peanut oil on the protein conformation and gel quality of Nemiperus virgatus surimi was evaluated. A significant reduction in gel strength, texture parameters and water holding capacity (WHC) of surimi was found as oil concentration increased (P < 0.05). However, compared with peanut oil, the gel strength, hydrophobic interaction and disulfide bond content of surimi gel containing oleogels increased by 6.919%, 32.635% and 12.409%, respectively, when the oil concentration was 10 g kg-1. Both oleogels and peanut oil could enhance the whiteness of surimi gel. Oleogels induced the unfolding of surimi proteins, and promoted the conformational shift from α-helix to β-sheet structure. Furthermore, oleogels filled the gaps of protein networks to make the microstructure of surimi gel more compact and uniform, improving the WHC and reducing the cooking loss. γ-Oryzanol+β-sitosterol-based oleogel alleviated the adverse influences of direct addition of peanut oil on the gel and textural properties of surimi products. © 2024 Society of Chemical Industry.

Formulation and Evaluation of Vancomycin Loaded Chitosan/Aloe Vera Hydrogel: A Novel Antibacterial Biopolymeric System

The combination of herbal and biopolymeric agents holds significant potential for enhancing wound healing. Aloe vera, known for its anti-inflammatory, antimicrobial, and regenerative properties, has long been used to treat wounds and burns. Chitosan, as a well-known biopolymer, promotes collagen synthesis, fibroblast recruitment and aiding granulation tissue formation. This study explored the formulation of a chitosan/Aloe vera hydrogel loaded with vancomycin, as a potential wound care product. The hydrogel was prepared using chitosan and aloe vera in 1:1 and 1:2 ratios. After homogenization, 1% vancomycin was incorporated. All physical characterizations, drug loading and drug release studies were performed on prepared formulations. Antimicrobial activity also was evaluated against Staphylococcus aureus and Pseudomonas aeruginosa. Moreover, both physical and performance properties of gels were assessed over three months under room temperature and refrigerated conditions. The study found that the gels remained stable, with no changes in color, flowability, uniformity, or viscosity during stability assessments. Both formulations released their entire drug content within two hours when kept at room temperature and in the refrigerator. No signs of separation or degradation were observed over the three-month period, demonstrating the gel’s stability. Formulations showed acceptable antimicrobial activity against both mentioned bacterial strains. In conclusion, the chitosan/Aloe vera gel containing vancomycin showed desirable properties, making it a promising candidate for wound healing. Its antimicrobial activity and ability to support tissue regeneration suggest it as a valuable treatment for accelerating the wound-healing process.

"Effect of Blanching Conditions on Color, Antinutrient, Paste and Gel Properties of Taro Flour"

"Effect of Blanching Conditions on Color, Antinutrient, Paste and Gel Properties of Taro Flour"

Gelation and dough‐forming properties of canary seed protein concentrate in comparison with commercial soy protein concentrate and vital wheat gluten

AbstractBackground and ObjectivesIn this study, a lab‐scale process was developed to aqueously de‐oil canary seed (yellow and brown‐seeded) flour and derive a protein concentrate. The protein concentrates prepared were evaluated for their gelation and bread dough‐forming properties.FindingsThe aqueous process successfully reduced the oil content in both yellow‐seed and brown‐seed roller‐milled flour. The protein concentrate prepared from yellow‐seed flour and brown‐seed flour had 74.9% and 68.6% purity (dry weight basis), respectively. Proteins showed high resistance to thermal denaturation (peak denaturation at 107°C). It was found that the least gelation concentration of both protein concentrates was 16% (w/w). There were no significant differences in viscoelastic properties and water holding capacity between the protein gels of these two canary seed types and the addition of salt did not noticeably improve these properties. Compared to canary seed, commercial soy protein showed better gelation properties. Both yellow and brown canary seed protein showed a good potential for improving bread dough strength when incorporated into a low‐gluten‐strength wheat flour and was comparable to commercial vital wheat gluten at 1%–3% (w/w) inclusion levels.ConclusionsThe new canary seed protein ingredients prepared by the solvent‐free aqueous‐based process hold good potential for application in food formulation based on their gelation and bread dough‐forming properties.Significance and NoveltyThe gelation and dough‐forming properties of canary seed were not previously studied; therefore, this study provides an insight into those properties for potential food applications for canary seed proteins, which is important for canary seed market diversification as a novel protein source.

Effect of ultrasound treatment on the emulsion gelling properties of PSE-like chicken myofibrillar protein

ABSTRACT The effects of ultrasound treatment (20 kHz, 0, 150, 300, 450, 600 W, 6 min) on the gel properties of PSE (pale, soft, and exudative)-like chicken myofibrillar protein (MP) emulsion gels were studied. When the ultrasound power increased from 0 W to 600 W, the water-holding capacity (WHC) and gel strength of PSE-like MP emulsion gel increased by 45.01% and 37.5%, respectively (p < 0.05), the storage modulus (G’) is increased and free water began to move in the direction of immobilized water, changed hydrogen bonds to other types of intermolecular force. Fourier transform infrared spectroscopy (FTIR) showed that ultrasound treatment promoted to the transformation from α-helix to β-sheet. The microstructure showed that the emulsion gel of MP after ultrasound treatment had a dense network structure. Ultrasound treatment effectively improved the gel properties of PSE-like chicken MP emulsion gels, which provides a new idea for improving the gel properties of PSE-like chicken protein.

Potential skincare benefits and self-healing properties of Lignosus rhinocerotis polysaccharides as affected by ultrasound-assisted H2O2/Vc treatment

Natural polysaccharides have been recognized as major bioactive components in skincare and wound care products. In this study, the skincare benefits and self-healing properties of Lignosus rhinocerotis polysaccharides (LRP) and its degraded products (DLRP-1, DLRP-2 and DLRP-3) by ultrasound assisted H2O2/Vc treatment (U-H/V) at different ultrasonic intensity (28.14, 70.35, and 112.56 W/cm2) were investigated. U-H/V altered the internal crystalline structure and microstructure of LRP, and enhanced the thermal stability. Due to the breakage of molecular chains after U-H/V, the moisture absorption of LRP was enhanced but the moisturizing property showed a different degree of reduction. U-H/V significantly improved the antioxidant, anti-tyrosinase and anti-inflammatory activities of LRP. Furthermore, the results of enzyme kinetic studies showed a mixed competitive-noncompetitive inhibition of tyrosinase activity by DLRP-3 and the inhibition constant of DLRP-3 on tyrosinase was 2.97 mg/mL. The apparent viscosity of LRP dispersions showed a first increasing followed by decreasing trend as ultrasonic intensity rose. U-H/V enhanced the viscoelastic properties of LRP gels without destroying their self-healing properties. This findings reveal that U-H/V is beneficial for improving the skincare efficacy of LRP, providing a theoretical foundation for the applicability of LRP in wound dressings.

Enhancing salt-induced gelation of egg yolk granules through pH-ultrasound combined treatment: A physicochemical and microstructural analysis

Salted duck eggs are a popular food product, but their high salt content and uneven salt distribution can reduce acceptability. This study investigated the effects of pH-high-intensity ultrasound combined treatment on the salt-induced gelation properties of egg yolk granules. The results showed that the pH5 + 150 W treatment group exhibited the best physical and gelation properties, with the smallest particle size (1597.33 nm), optimal dispersibility (PDI 0.29), and good stability. The gelation properties of this group also demonstrated excellent springiness (0.30 mm), cohesiveness (0.56), and gumminess (0.05 N). Furthermore, the pH5 + 150 W group had the highest water holding capacity of 97.42 % and relatively high hydrophobicity (173.39 μg). Notably, it also showed high oil exudation (2.83 %) and good sandiness (62.07 %). The pH5 + 150 W led to a significant redshift of the fluorescence peak at 335 nm and an enhancement of the peak intensity at 562 nm compared to the control group. Structural characterization revealed a more ordered protein structure and a uniform gel structure with enhanced electrostatic repulsion between oil droplets. Secondary structure analysis of the proteins showed a significant reduction in α-helix and β-sheet, while β-turn and random coil increased. In summary, the pH5 + 150 W treatment displayed the best gelation properties, providing theoretical guidance for enhancing the processing performance of yolk and expanding their application in the food industry.

Design of Aerated Oleogel-Hydrogel Mixtures for 3D Printing of Personalized Cannabis Edibles.

Cannabis seed oil oleogel structured with Glycerol Monostearate (20% w/w) was mixed with xanthan gum hydrogel (2% w/w) at different ratios ranging from 0% w/w hydrogel to 75% w/w hydrogel, using a syringe-to-syringe apparatus, for the preparation of 3D-printable food inks. This process enabled the simultaneous blend of oleogel and hydrogel phases and the incorporation of air in a reproducible and accurate manner. The printability of bigel inks with different mass ratios was evaluated by using a conventional benchtop food 3D printer. The printability of the inks was found to be negatively affected by the presence of higher portions of the hydrogel phase, while the printing performance of pure cannabis seed oil oleogel was superior compared to the printing performance of the bigel inks. The physicochemical properties of hybrid gels were investigated with rheological studies, thermophysical studies (Differential Scanning Calorimetry), Polarized Light Microscopy, and Confocal Laser Scanning Microscopy. The microstructure of the aerated inks was affected by the presence of a higher oleogel fraction, in terms of air bubble shape and distribution. The addition of hydrogel at concentrations higher than 50% w/w had a strong negative effect on the mechanical properties of the inks leading to a partial collapse of the printed structures and subsequently to poor printing performance.

Frabrication of carboxymethylchitin nanofibers and fish gelatin hybrid gels with robust gel performance

Compared to animal gelatin, the application of fish gelatin (FG) in the food industry is limited due to its lower gel hardness, gelation temperature, and melting temperature. To address these issues, we developed hybrid gels using carboxymethyl chitin nanofibers (CMC-NFs) with FG to enhance its gel properties. The chitin was carboxymethylated by monochloroacetic acid, increasing the negative potential from −6 mV to −35 mV. This modified chitin was then defibrillated into CMC-NFs through high-pressure homogenization to improve its water dispersibility. The addition of 0.1% CMC-NFs significantly increased the hardness of FG gels from 533 g to 989 g, which was notably higher than the ∼600 g hardness of porcine gelatin. Additionally, the gelation and melting temperatures of FG reached 17 °C and 32 °C, respectively, which are very close to the 20 °C and 35 °C of porcine gelatin. Mechanistic studies revealed that FG and CMC-NFs (0.1%) molecules formed a synergistic gel network, facilitated by hydrogen bonding and hydrophobic interactions. This interaction significantly increased the α-helix content in the secondary structure of the FG protein from 15.26% to 21.18%, thereby enhancing the FG-dominated three-dimensional network structure with CMC-NF molecules. Increasing the concentration of CMC-NFs further elevated the gel's melting temperature while reducing its hardness due to phase separation. This study not only presents a viable method for enhancing the gelling properties of modified FG but also offers a feasible solution for expanding FG's applications in the food industry.

Improvement of quercetin bioaccessibility by whey protein isolate/D-tagatose conjugates: Effect on the structural characterization through simultaneous rheological and FTIR techniques

To improve the performance of whey protein isolates (WPI) as an encapsulation agent in the food industry, we investigated the formation mechanism of WPI and D-tagatose (DT) conjugates using simultaneous rheological and Fourier-Transform infrared spectroscopy (FTIR) techniques, and analysed its effects in encapsulating quercetin (Que). The degree of glycosylation of the conjugates increased to 18 % after heating treatment, whereas particle size and potential decreased to 64 nm and −39 mV, with WPI/D10 showing the lowest value. Simultaneous rheological and Fourier transform infrared analyses showed that the structure of the WPI/DT complexes changed, and the gel properties were much better than those of WPI. Several new peaks appeared at 2961, 1525, 1450, 1392, and 1236 cm-1, indicating that adding DT affected the structure of WPI. DT promoted secondary structural changes in WPI by increasing the degree of hydrocarbon chain, O-H group vibration, and C-O stretching. The WPI/DT conjugates increased the solubility of Que to 60.74 % and ABTS clearance to 73.98 %. The study may offer a theoretical foundation for using WPI/DT-encapsulated Que in food industry.