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The molecular weight (MW) of oligosaccharides on gel properties of myofibrillar protein (MP) at high temperature remains unclear. In this study, it was found that chitosan oligosaccharides (CO) with different MW all significantly alleviated the textural deterioration of MP gel with high-temperature treatment. Moreover, MP-CO gel with the largest MW had the highest breaking force and the lowest cooking loss. Low-field NMR results further indicated that MP-CO gel with larger MW of CO had gradually increased relaxation rate, thus binding water more tightly. Rheological and microrheological tests suggested the addition of CO with larger MW resulted in much tighter gel network. These results indicated that CO with larger MW improved the quality of MP gel more effectively, which was because CO with larger MW inhibited aggregation of MP to a larger extent, resulting in smaller MP aggregates. Then MP-CO gel with much denser and more homogeneous structure was formed. Besides, MP-CO gel with larger MW of CO had higher content of β-sheet, resulting in MP gel with more ordered structure and better gel quality. Therefore, this study provided theoretical guidance for choosing the appropriate CO in improving texture of high temperature meat products., Competing Interests: Declaration of competing interest The authors declared that there were no competing financial interests or personal relationships that could influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The main aim of the current study was to research the effect of the degree of konjac deacetylation on the rheological and textural properties of konjac glucomannan (KGM) and κ-carrageenan blends. A series of deacetylated konjac glucomannan (Da-KGM) with different degrees of deacetylation (0, 20.35%, 35.62%, 57.19%, and 74.01%) was prepared by a heterogeneous deacetylation method. The rheological and textural properties of mixed sols and gels of Da-KGM with different degrees of deacetylation and κ-carrageenan were determined. The results showed that the viscosities of mixed sols of Da-KGM and κ-carrageenan decreased with increasing degree of deacetylation. The partial removal of acetyl groups from konjac glucomannan could significantly improve the hardness and springiness of mixed gels of KGM and κ-carrageenan. Meanwhile, decreasing the acetyl content could decrease the syneresis of mixed gels. By regulating the deacetylation degree of konjac, gels with high gel strength could be prepared, which provides a new idea for the production of high-strength gelatin food., (Copyright © 2018. Published by Elsevier B.V.)

To broaden the application of cellulose nanocrystals (CNCs) in the field of biopolymer nanocomposites, a systematic assessment of the viscoelastic properties of CNC suspensions in the presence of glycerol (Gly) and/or sodium chloride (NaCl) was conducted. The viscosity, storage modulus (G'), and loss modulus (G'') increased with increasing concentrations of CNCs and Gly, respectively. Dramatically, the G' and G'' values were raised and tanδ (<1) decreased with the increasing addition of NaCl, indicating that the elastic properties of CNCs in NaCl solutions continuously strengthened, thereby the gel-like response of the network was enhanced. Moreover, the addition of 40% Gly significantly increased the values of G' and G'' for CNCs in NaCl solutions. This work demonstrates new findings related to the rheological properties of CNC gels with Gly/NaCl, and accounts for the interaction mechanisms between CNCs and CNCs/Gly/NaCl, with electrostatic interactions, hydrogen bonds, van der Waals forces, and Na + bridging. We wish our study could better serve for future works based on design of CNCs in biomedical and packaging materials industries., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Rheological properties of a new microbial polysaccharide, diutan gum in aqueous solution have been systematically investigated. It is found that molecular aggregates of diutan gum can be formed at a very low concentration (0.12 g/L), and the mechanism of thickening by diutan gum is proposed. The viscosity retention rate of diutan gum changes little when increasing the temperature from 298 K to 348 K or in a high salinity solution (55.5 g L(-1)). Gel structure can be formed in the diutan gum solution, owing to the finding that the dynamic modulus has an exponential relationship with the concentration. The gel properties of diutan gum are not sensitive to temperature, and are virtually independent of cationic environment (Na(+) and Ca(2+)). The temperature/salt tolerance of the diutan gum solution is mainly attributed to its perfect double helix molecular conformation, the location of the side chains of its molecules, and its water retention capacity., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Human blood plasma is a material used to generate tissue equivalents due to presence of fibrinogen. However, gels formed using human blood plasma has weak mechanical properties. In this study, different mixtures of sodium alginate and blood plasma were performed and evaluated. By determining ζ potential can be established the stability of the plasma-alginate mixture and by dynamic rheology can determine the most suitable parameters for the gelation of the above mixtures, when calcium chloride is used as a crosslinker. Experimental results evidence an increment in ζ potential at alginate concentrations of 0.8% and 1.6% with a resulting pseudoplastic behavior of evaluated mixtures, which described the homogenization of the mixture. On the other hand, mixtures were gelled by using aspersion of calcium chloride and characterized by dynamic rheology. Solid behavior is dominant in all range of frequency sweep test between 0.1Hz and 100Hz. Finally, the ultimate tensile strength of a gel reach 6.36938±0.24320kPa, which is enough for manual handling of the gel. Between the tasks of the gel would be used for cell entrapment, for controlled release of drugs or in the manufacture of wound dressings., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Fruit processing by-products could represent a sustainable ingredient for developing innovative dairy products. The present study was conducted to develop a novel functional yogurt by adding bilberry pomace powder (BPP) at 0.5%, 1.0%, and 1.5% (w/w) levels in stirred-type yogurt production to confer color and to increase the dietary fiber and polyphenol content. Physicochemical properties of the yogurt samples, including color parameters, titratable acidity, pH, water holding capacity (WHC), and syneresis, as well as textural and rheological properties, were evaluated in yogurts on the 1, 14, and 28 days of refrigerated storage (4 °C). In addition, total phenolic content, total anthocyanin content, and radical scavenging activity were determined in yogurts, and sensory analysis was conducted. The results showed that BPP is a valuable source of polyphenols, dietary fiber, and oils rich in n-3 polyunsaturated fatty acids (n-3 PUFAs, n-6/n-3 ratio = 0.91). The incorporation of BPP imparted an attractive purple color to the yogurts, increased WHC, and reduced syneresis. Moreover, the addition of BPP improved the rheological properties, demonstrating that a more dense and stable yogurt gel network structure was obtained than the control. The yogurt enriched with 1.0% BPP received the highest scores for color, consistency, taste, and overall acceptability. Hence, bilberry pomace powder might be used as an ingredient to improve the nutritional and functional value of yogurts. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chinese herbs are a huge treasure trove of natural products and an important source of many active molecules. The theory of traditional Chinese medicine compatibility (TCMC) is widely applied in clinical practice, but its mechanism is still ambiguous. This study aims to open a new window for this predicament by studying the interaction between the main active ingredients from a drug pair. Carrier-free assembly of natural products improves the shortcomings of traditional nanodelivery systems and opens a new path for the development of new nanomaterials. The drug pair "Pueraria and Hedyotis diffusa" has been commonly used in clinical practice, with a predominant therapeutic effect. This study is devoted to the study of the binary small molecule co-assembly of the main active molecules from the drug pair. In this study, we introduce a carrier-free composite gel, formed by the co-assembly of puerarin (PUE) and deacetylasperulosidic acid (DAA) via non-covalent bonds including π–π packing, intermolecular hydrogen bonding, and C=O π interactions. With a strain point 7-fold higher than that of P gel, the P − D gel exhibited favorable rheological properties. The survival rate of SW1990 cells in the P − D group was only 21.39% when the concentration of administration reached 200 μM. It thus demonstrated activity in inhibiting SW1990 cells' survival, suggesting potential in combating pancreatic cancer. Furthermore, this research offers a valuable concept for enhancing the mechanical properties and bioactivity of hydrogel materials through the utilization of a multi-component natural small molecule co-assembly approach. More importantly, this provides new ideas and methods for the treatment of pancreatic cancer and the analysis of traditional Chinese medicine compatibility theory. [ABSTRACT FROM AUTHOR]

Jam, as a common processed fruit product, has a long history of consumption and is widely loved by consumers due to its diverse products and rich nutrition. The texture of traditional jam can only be formed under high sugar (55%–75%) and highly acidic (pH 2.0–3.5) conditions, which is a challenge for the production of low-sugar jam. In addition, the texture of jam is vulnerable to damage during transport and storage, leading to jam quality deterioration. Food thickeners, food additives that increase the viscosity, consistency and gel strength of liquid foods, are widely used for promoting the formation of the texture of low-sugar jam and maintaining its stability during transport and storage. In this article, the deterioration phenomenon and formation theory of jam texture are reviewed. The thickening or gelling mechanism of food thickeners (e.g., pectin) and their application in jam are described with a focus on the effects of food thickeners on the sensory attributes, texture, rheological properties, and microstructure of jam. Moreover, several possible future research directions are proposed, aiming to provide ideas for the development and application of thickeners in jam.

Hypothesis: Capillary suspensions offer a new approach to generate novel materials. They are ternary liquid-liquid-solid systems characterized by particles connected by liquid bridges of one fluid suspended in a second immiscible bulk fluid. The viscosity of the bulk liquid can be modulated to customize the structure and rheological properties of capillary suspensions. Experiments and simulations: Using experiments and numerical simulations, we investigated capillary suspensions in the pendular state, using silica particles and water as a bridging liquid. To modulate the viscosity of the bulk fluid, we use different ratios of either dodecane and diisononyl phthalate, or silicone oils with varying chain lengths as bulk liquids. The rheological behavior was characterized using the maximum storage and loss moduli and the yielding behavior. This was related to structural changes of the systems, which was visualized using confocal laser scanning microscopy. In addition, we used Molecular Dynamics (MD) simulations to gain more insights into the behavior of two particles connected by a liquid bridge for various bulk liquids. Findings: Experiments show that higher bulk liquid viscosity reduces strength, yield stress, and yield strain in capillary suspensions, which is partly attributed to a reduced inter-connectivity of the percolating network. This is caused by the breakup of liquid bridges occurring at shorter distances in the presence of highly viscous bulk liquids, as indicated by numerical simulations.   [ABSTRACT FROM AUTHOR]

In this study, the effects of four Hofmeister salts (KCl, NaCl, CaCl2 and MgCl2) at different concentrations (0.02, 0.04 and 0.06 mol/L) on gel properties and rheological properties of soy protein isolate (SPI) were systematically explored. The results showed that the addition of salt ions could improve the gel strength of SPI, but higher concentrations (0.04 and 0.06 mol/L) of CaCl2 and MgCl2 reduced the gel stickiness of the samples. In the dynamic rheological test, each salt ion increased the storage modulus (G’) and loss modulus (G”) of the samples to varying degrees. Higher concentrations of CaCl2 and MgCl2 caused excessive aggregation of SPI, whereas lower concentrations of CaCl2 and MgCl2 exerted an opposite effect. In the temperature sweep test, CaCl2 and MgCl2 changed the trend of G’ and G”, while KCl and NaCl simply increased G’ and G” without changing their trend. In the steady rheological test, higher concentrations of CaCl2 and MgCl2 reduced the apparent viscosity and shear force of the samples, while an opposite effect was observed under the other salt conditions. The decreasing order of the effects of higher concentrations of salt ions on the apparent viscosity and shear force was K+ > Na+ > Mg2+ > Ca2+. In summary, at specific salt ion concentrations (0.04 and 0.06 mol/L), the changes in gel and rheological properties of SPI were consistent with the Hofmeister effect.

Summary: The purpose of this experiment was to explore the improvement of tussah pupa powder on the deterioration of pork batter emulsion gel by using proteomics, distribution of moisture, rheological properties and surface hydrophobicity. The results showed that the myosin decomposed as the heating temperature increased; as the increase of the addition proportion of tussah pupa powder at each sterilisation temperature point, compared to the control group, the pH of a pork batter emulsified gel showed a significant increased trend (P < 0.05); the low molecular weight proteins or formed oligomers of tussah pupa powder could be used as fillers to participate in the formation process of gel network; the vitellogenin of tussah pupa powder could form a 'skeleton' in the pork batter system; as the sterilisation temperature at 100 °C (30 min) and 110 °C (30 min), the surface hydrophobicity was the largest as the addition amount 2%. In short, the tussah pupae powder could improve the deterioration characteristics of the pork batter emulsified gel by influencing the pH, surface hydrophobicity and the formation of gel network of pork batter system. This research provided theoretical support for improving the process property of the meat products. [ABSTRACT FROM AUTHOR]

This study aimed to produce apple and carrot juice-based healthy snacks with unique sensory properties of selected fruit and vegetable with a 3D food printer. It was thought that these snacks will be an alternative for those who do not like to consume fruits and vegetables in their natural form and/or for people who cannot consume fruits and vegetables due to their texture (elders, people with swallowing difficulty). Minimum starch concentration required for gelation of apple and carrot juice was determined as 5%. Rheological properties of disintegrated gels were determined and these disintegrated gels were processed in 3D printer. Apple and carrot juice-based 3D products with 97% printability and 98% stability were obtained. According to sensory analysis results, general acceptance scores remained below medium value. Moreover, physicochemical and thermal properties of the products were determined, and effects of printing speed and filling rate on printing quality were examined. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to prepare water-in-oil-type gelled protein emulsions. Sorghum, chickpea, and barley proteins were extracted from the seed flours with an alkaline procedure, and 2% protein solutions were used as an aqueous phase with Span 20 emulsifier to create sunflower oil emulsion gels. Prepared gels were analysed for main physicochemical properties, polymorphism, and rheology. Results showed that stable emulsion gels were creamy-greenish in colour and had mechanical stability. They included β and β′ type fat crystals. Rheological analyses indicated that they were soft-gel-like preparates, having certain levels of structural recovery ability after shear. These emulsion gels could be spreadable-fat-like products or shortening alternatives in processed foods. They might provide an extra advantage due to plant protein content. Food application studies are anticipated in future studies. [ABSTRACT FROM AUTHOR]

Summary: Debranched starch (DBS) is widely used for the preparation of retrograded resistant starch type 3 due to its linear molecular feature. Upon application, interactions of the DBS with food ingredients can cause rheological and textural changes in cooked foods. This study aimed to investigate the individual effects of salt, sucrose and native starch at varying concentrations on gelation and rheological behaviour of debranched cassava starch (DBCS). Adding salt (NaCl; 0.5%–2.0% w/w) delayed gel formation. Frequency sweep tests of these gels indicated an apparent elastic solid‐like behaviour with or without salt. However, the gel weakened with increasing salt concentration. This result was confirmed by reduced gel hardness and gumminess. Unlike salt, adding sugar (sucrose; 5%–15% w/w) and native cassava starch (0.5%–20.0% w/w) enhanced gel formation. Gels incorporating sucrose or native starch displayed elastic solid‐like behaviour and had higher stiffness than the control. However, the dependence of their elastic moduli on frequency differed. The G′ and G″ of DBCS gels with native starch fluctuated with frequency. Texture analysis confirmed that the gels incorporating sucrose or native starch had higher strength than the control. In conclusion, salt delays gelation and reduces gel strength while sucrose and native starch show the opposite effects. Further research on the effects of other food ingredients especially protein and lipid as well as mixed ingredients on DBS gel properties is needed to gain a better understanding of DBS gel behaviours in real food systems. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Agarose forms a homogeneous thermoreversible gel in an aqueous solvent above a critical polymer concentration. Contrary to the prevailing consensus, recent confirmations indicate that agarose gels are also stable in non-solvents like acetone and ethanol. A previous study compared gel characterisations and behaviours in water and ethanol, discussing the gelation mechanism. In the current work, the ethanol gel is exchanged with water to explore the potential reversibility of the displacement of water in agarose. Initially, the structure is characterised using 1H NMR in DMSO-d6 and D2O solvents. Subsequently, a very low yield (0.04) of methyl substitution per agarobiose unit is determined. The different gels after stabilisation are characterised using rheology, and their physical properties are compared based on the solvent used. The bound water molecules, acting as plasticizers in aqueous medium, are likely removed during the exchange process with ethanol, resulting in a stronger and more fragile gel. Next, the gel obtained after the second exchange from ethanol back to water is compared with the initial gel prepared in water. This is the first time where such gel has been characterised without undergoing a phase transition when switching from a good solvent to a non-solvent, and vice versa, thereby testing the reversibility of the solvent exchange. Reversibility of this behaviour is demonstrated through swelling and rheology experiments. This study extends the application of agarose in chromatography and electrophoresis. [ABSTRACT FROM AUTHOR]

This study investigated a nanostructured lipid carrier (NLC)-gel system containing luteolin (LUT), a potential drug delivery system for the treatment of psoriasis. LUT-NLC was prepared by solvent emulsification ultrasonication method. The particle size was 199.9 ± 2.6 nm, with the encapsulation efficiency of 99.81% and drug loading of 4.06%. X-ray diffractometry (XRD), Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) were used to characterize the LUT-NLC. The NLC was dispersed in Carbomer 940 to form the NLC based gel. The rheological characteristics of LUT-NLC-gel showed an excellent shear-thinning behavior (non-Newtonian properties) and coincided with the Herschel-Bulkley model. LUT-NLC-gel (78.89 μg/cm2) exhibited better permeation properties and released over 36 hours than LUT gel (32.17 μg/cm2). The dye-labeled LUT-NLC presented intense fluorescence in the epidermis and dermis by the visualization of fluorescence and confocal microscopy, and it could accumulate in the hair follicles. The effect of LUT-NLC-gel on imiquimod-induced psoriasis mice was evaluated by psoriasis area severity index scoring, spleen index assay, histopathology, and inflammatory cytokines. These results confirmed that LUT-NLC-gel with high dose (80 mg/kg/day) remarkably reduced the level of inflammatory and proliferation factors such as TNF-α, IL-6, IL-17, and IL-23 in both skin lesions and blood. LUT-NLC-gel improved the macroscopic features. Therefore, the LUT-NLC-gel had great potential as an effective delivery system for skin diseases. [ABSTRACT FROM AUTHOR]

Fruit processing by-products could represent a sustainable ingredient for developing innovative dairy products. The present study was conducted to develop a novel functional yogurt by adding bilberry pomace powder (BPP) at 0.5%, 1.0%, and 1.5% (w/w) levels in stirred-type yogurt production to confer color and to increase the dietary fiber and polyphenol content. Physicochemical properties of the yogurt samples, including color parameters, titratable acidity, pH, water holding capacity (WHC), and syneresis, as well as textural and rheological properties, were evaluated in yogurts on the 1, 14, and 28 days of refrigerated storage (4 °C). In addition, total phenolic content, total anthocyanin content, and radical scavenging activity were determined in yogurts, and sensory analysis was conducted. The results showed that BPP is a valuable source of polyphenols, dietary fiber, and oils rich in n-3 polyunsaturated fatty acids (n-3 PUFAs, n-6/n-3 ratio = 0.91). The incorporation of BPP imparted an attractive purple color to the yogurts, increased WHC, and reduced syneresis. Moreover, the addition of BPP improved the rheological properties, demonstrating that a more dense and stable yogurt gel network structure was obtained than the control. The yogurt enriched with 1.0% BPP received the highest scores for color, consistency, taste, and overall acceptability. Hence, bilberry pomace powder might be used as an ingredient to improve the nutritional and functional value of yogurts.

Boza is an indigenous, traditional, low-alcohol and highly viscous beverage prepared by fermenting cereals. Its thick and gel-like consistency make it suitable for consumption via spoon. Although boza is a nutritious beverage, its protein content is very low (<2%). A new type of boza was developed by incorporating nonfat dry milk (NFDM) to elevate the protein content of the beverage. Different NFDM amounts (10 to 40% w/v) were added to determine the best concentration and fermentation time based on the refractive index and pH values at room temperature (0–48 h). The best sample was further characterized by rheological analyses and Fourier transform infrared (FTIR) spectroscopy. The sample with 10% NFDM was the best, as fermentation was successfully performed, and further addition of NFDM increased the initial pH. The refractive index and pH decreased from 21.9 ± 0.1 to 11.8 ± 0.1 and 5.77± 0.50 to 4.09 ± 0.35 during fermentation, respectively. The samples exhibited shear-thinning, solid-like behavior, and a gel-like structure. FTIR analysis by independent modeling of class analogy (SIMCA) demonstrated that unfermented slurry and the fermented product could be effectively differentiated. With the addition of 10% NFDM, the increase in the protein content of the boza medium became significant. [ABSTRACT FROM AUTHOR]

Nanopapers fabricated from cellulose nanofibers (CNFs) drastically swell to form hydrogels when they are in contact with water. This gelation makes contrast with conventional papers that simply deform without drastic volume increase. While the volume increase is qualitatively obvious from the macroscopic visual inspection, its quantitative understanding is nontrivial because of the difficulty in the detection of the boundary between the nanopaper hydrogel and the residual or extra water. In this study, we use single particle tracking (SPT) to reveal the swelling-based gelation phenomenon of cellulose nanopapers. The diffusive dynamics of probe particles uncovers the transient process of swelling, and equilibrium analysis reveals the dependence of volume increase fundamentally dependent on the amount of water to be in contact with the nanopapers. Comparison with the aqueous CNF dispersion without drying reveals the difference in the texture of the nanopaper hydrogels from them. [ABSTRACT FROM AUTHOR]

The effect of γ-irradiation of the gelling agent Carbomer 141G, which is lightly crosslinked polyacrylic acid, on the rheological properties of gels based on the carbomer has been studied. It has been found that an increase in the dose of γ-irradiation in air has a destructive effect on the polymer, leading to a decrease in rheological parameters, such as viscosity, yield strength, and hysteresis area. Irradiation of the carbomer in air with doses greater than 300 kGy leads to a significant decrease or the complete loss of its gel-forming properties. At the same time, irradiation of the carbomer with the same dose in vacuum causes as small a decline in viscosity as 2% compared to the initial systems. It has been established that the optimal gelling agent for obtaining stable antibacterial gels is the carbomer irradiated with a dose of 30 kGy. [ABSTRACT FROM AUTHOR]

Objective: Improve 3D printing performance and gel properties of silver carp surimi system. Methods: By optimizing 3D printing parameters, the 3D printing process is associated with material rheological properties and 3D printing performance. The effects of sodium chloride addition on rheological properties, 3D printing properties, gel strength, moisture properties and microstructure of silver carp surimi were investigated. Results: The addition of sodium chloride decreased the loss modulus of surimi in a dose-dependent manner, but significantly improved the shear recovery performance, reduced the cooking loss of surimi system and increased the water retention of surimi system. The best gel strength and the densest microstructure of silver carp were obtained when the sodium chloride content was 2.5%. Conclusion: Adding proper amount of sodium chloride can improve the 3D printing performance and gel properties of surimi products.

The rheological and viscoelastic properties of hybrid formulations composed of vehicles designed for cutaneous topical application and loaded with ultradeformable liposomes (UDL) were assessed. UDL were selected for their established ability to transport both lipophilic and hydrophilic compounds through the skin, and are applicable in pharmaceuticals and cosmetics. Formulations underwent flow analysis and were fitted to the Herschel–Bulkley model due to their prevalent non-Newtonian behavior in most cases. Linear viscoelastic regions (LVR) were identified, and G′ and G″ moduli were determined via frequency sweep steps, considering the impact of temperature and aging. The formulations exhibited non-Newtonian behavior with pseudoplastic traits in most cases, with UDL incorporation inducing rheological changes. LVR and frequency sweep tests indicated predominantly elastic solid behavior, with G′ higher than G″, at different temperatures and post-production times. Tan δ values also illustrated a predominant solid-like behavior over liquid. This study provides pivotal insights into the rheological and viscoelastic features of topical formulations, emphasizing the crucial role of meticulous vehicle and formulation selection when incorporating UDL or analogous liposomal drug delivery systems. [ABSTRACT FROM AUTHOR]

A new class of active organic crosslinking agents for the vulcanization of NBR based on halogenmethyl-containing compounds has been found, allowing improvement significantly in the rheological and structural parameters of NBR. Gel content and Mooney viscosity in binary systems after plastification on rollers were studied. The sol fraction of cross-linked NBR (SKN-40+TCMCC) was found to be characterized by a bimodal MWD. Abnormally high value of W/ns of sol fractions is associated with the bimodal nature of their MWD and indicates the presence of gel in the elastomer. The value of η of the sol fractions in cross-linked NBR was found to be insignificant. The sol fraction of cross-linked HCPX elastomer was shown to have lower values of the specified parameters and lower content of highmolecular-weight fractions. The branching density ρ of macromolecules of sol fraction of cross-linked NBR was 1.90-2.3·10-3, i.e. on average corresponded to one monomer unit and two hundred branching nodes per molecule. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this review, today's state of the art in the rheology of gels and transition through the yield stress of yielding liquids is discussed. Gels are understood as soft viscoelastic multicomponent solids that are in the incomplete phase separation state, which, under the action of external mechanical forces, do not transit into a fluid state but rupture like any solid material. Gels can "melt" (again, like any solids) due to a change in temperature or variation in the environment. In contrast to this type of rheology, yielding liquids (sometimes not rigorously referred to as "gels", especially in relation to colloids) can exist in a solid-like (gel-like) state and become fluid above some defined stress and time conditions (yield stress). At low stresses, their behavior is quite similar to that of permanent solid gels, including the frequency-independent storage modulus. The gel-to-sol transition considered in colloid chemistry is treated as a case of yielding. However, in many cases, the yield stress cannot be assumed to be a physical parameter since the solid-to-liquid transition happens in time and is associated with thixotropic effects. In this review, special attention is paid to various time effects. It is also stressed that plasticity is not equivalent to flow since (irreversible) plastic deformations are determined by stress but do not continue over time. We also discuss some typical errors, difficulties, and wrong interpretations of experimental data in studies of yielding liquids. [ABSTRACT FROM AUTHOR]

The process of phase separation in elastic solids and viscous fluids is of fundamental importance to the stability and function of soft materials. We explore the dynamics of phase separation and domain growth in a viscoelastic material such as a polymer gel. Using analytical theory and Monte Carlo simulations, we report a domain growth regime in which the domain size increases algebraically with a ripening exponent α that depends on the viscoelastic properties of the material. For a prototypical Maxwell material, we obtain α = 1, which is markedly different from the well-known Ostwald ripening process with α = 1=3. We generalize our theory to systems with arbitrary power-law relaxation behavior and discuss our findings in the context of the longterm stability of materials as well as recent experimental results on phase separation in cross-linked networks and cytoskeleton. [ABSTRACT FROM AUTHOR]

In this work we built up and tested diffusion cells designed to obtain polysaccharide hydrogels by ionotropic gelation. The objective was to obtain gel samples that emulated the wall material of encapsulation beads but, unlike them, have appropriate size and shape for measurement of their structural properties, since these are of paramount importance for the protection, carry and delivery of bioactive compounds. Three polysaccharides widely used for encapsulation and with different gelation mechanisms were tested: kappaliota-carrageenan (which gels mainly in the presence of K+ ions), and sodium alginate and low methoxyl pectin (which both gel in the presence of Ca2+ ions). The diffusion cells consisted of two nitrocellulose membrane filters supported between three rings made by 3D printing. They were filled with the polysaccharide solution, hermetically tightened with screws and nuts, and submerged into the saline solution. The membrane filters effectively avoided the loss of the polysaccharide solution but allowed the diffusion of the ions (either Ca24 or K+) into the polysaccharide solutions to promote their gelation. Firm, self-standing gels were obtained, and their rheological and mechanical properties were successfully measured. Samples of different shapes and sizes could be obtained with this technique, for other types of measurement. [ABSTRACT FROM AUTHOR]

Anchote is a tuber crop indigenous to Ethiopia. Starch hydration properties and important gel characteristics which include: color, gel rheological properties (at 2, 4, 6, 8, and 10% starch:water w/w) and gel texture evolution (at 10% starch:water w/w), during 0 to 192 h storage (at 4 °C), of anchote starches isolated from four anchote cultivars (Desta 01, Desta 24, white and red) were evaluated and compared with potato and cassava starches (PS and CS). The lightness (L*) and whiteness scores of the anchote starch ranged up to >95, with slight differences among the cultivars, making them pure starches. Swelling power (SP) and water solubility index (WSI) of the anchote starches increased with increasing cooking temperature (40, 50, 60, 70, 80 and 90 °C), and their rate of increase varied significantly with the control starches, as follows: CS < anchote starches < PS. Anchote starch gels resisted higher stresses before breaking their structure and showed higher elasticity with lower (tan δ)1 values than PS and CS gels. They also had greater viscoelastic moduli even at lower concentrations than the PS and CS gels, and their stability increased with increasing concentration. The study of the gels' texture evolution during storage revealed that anchote starch gels had significantly higher (≥40%) initial and final (after 192 h) hardness and were less adhesive than the PS gel. Despite some significant differences in the studied starch gel quality parameters among the starches from the anchote cultivars, the results suggested their promising potential as additional new materials in the development of food products, specifically as a functional ingredient for the formulation of gel-like products. [ABSTRACT FROM AUTHOR]

Natural rubber, given its natural origin, is not composed exclusively of polyisoprene chains, but also of so-called non-rubber components such as proteins or phospholipids. Such compounds are responsible for gel formation - insoluble phase if natural rubber (NR) is in a proper solvent. Gel is one of the causes why the behavior of NR is non-standard during processing. The gel content is determined by various methods, while it is not examined in detail which method has a stronger relation to the rheological behavior of rubber. Three different methods (filtration, dissolution in toluene for three different times and Soxhlet extraction) used for determining the gel content of NR are compared in this paper. Analytical (ash content, molar mass measurement, ...) and rheological (Mooney viscosity, rubber process analyzer measurements, ...) measurements are performed and their results are correlated with the gel content values. [ABSTRACT FROM AUTHOR]

Aronia melanocarpa polyphenols (AMP) have good nutritional values and functions. This study aimed to explore the printability and storage properties of AM gels in 3D food printing (3DFP). Therefore, 3DFP was performed on a loaded AMP gel system to determine its textural properties, rheological properties, microstructure, swelling degree and storage performance. The results revealed that the best loading AMP gel system to meet the printability requirements of 3DFP processing was AM fruit pulp:methylcellulose:pea albumin: hyaluronic acid = 100:14:1:1. Compared with other ratios and before 3DFP processing, the best loading AMP gel system processed by 3DFP exhibited the lowest deviation of 4.19%, the highest hardness, the highest elasticity, the least adhesion, a compact structure, uniform porosity, difficulty in collapsing, good support, a high degree of crosslinking, and good water retention. Additionally, they could be stored for 14 d at 4 °C. After post-processing, the AMP gel had a favorable AMP release rate and good sustained release effect in gastrointestinal digestion, which conformed to the Ritger–Peppas equation model. The results revealed that the gel system had good printability and applicability for 3D printing; as well, 3DFP products had good storage properties. These conclusions provide a theoretical basis for the application of 3D printing using fruit pulp as a raw material. [ABSTRACT FROM AUTHOR]

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Boza is an indigenous, traditional, low-alcohol and highly viscous beverage prepared by fermenting cereals. Its thick and gel-like consistency make it suitable for consumption via spoon. Although boza is a nutritious beverage, its protein content is very low (w/v) were added to determine the best concentration and fermentation time based on the refractive index and pH values at room temperature (0–48 h). The best sample was further characterized by rheological analyses and Fourier transform infrared (FTIR) spectroscopy. The sample with 10% NFDM was the best, as fermentation was successfully performed, and further addition of NFDM increased the initial pH. The refractive index and pH decreased from 21.9 ± 0.1 to 11.8 ± 0.1 and 5.77± 0.50 to 4.09 ± 0.35 during fermentation, respectively. The samples exhibited shear-thinning, solid-like behavior, and a gel-like structure. FTIR analysis by independent modeling of class analogy (SIMCA) demonstrated that unfermented slurry and the fermented product could be effectively differentiated. With the addition of 10% NFDM, the increase in the protein content of the boza medium became significant.

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

PLGA-based in situ forming implants (ISFI) often require a high amount of potentially toxic solvents such as N methyl-Pyrrolidone (NMP). The aim of the present study was to develop lipid in-situ-forming oleogels (ISFOs) as alternative delivery systems. 12-Hydroxystearic acid (12-HSA) was selected as the oleogelling agent and three different oleoformulations were investigated: (a) 12-HSA, peanut oil (PO), NMP; (b) 12-HSA, medium-chain triglycerides (MCT), ethanol; (c) 12-HSA, isopropyl myristate (IPM), ethanol. The effects of the 12-HSA concentration, preparation method, and composition on the mechanical stability were examined using a texture analysis and oscillating rheology. The texture analysis was used to obtain information on the compression strength. The amplitude sweeps were analyzed to provide information on the gel strength and the risk of brittle fractures. The frequency sweeps allowed insights into the long-term stability and risk of syneresis. The syringeability of the ISFOs was tested, along with their acute and long-term cytotoxicity in vitro. The developed ISFOs have the following advantages: (1) the avoidance of highly acidic degradation products; (2) low amounts of organic solvents required; (3) low toxicity; (4) low injection forces, even with small needle sizes. Therefore, ISFOs are promising alternatives to the existing polymer/NMP-based ISFIs. [ABSTRACT FROM AUTHOR]

The aim of the study is to develop and evaluate the printability of k-carrageenan inks enriched with callus tissue of lupin (L. angustifolius) and to determine the effect of two lupin calluses (LA14 and LA16) on the texture and digestibility of 3D-printed gel. The results demonstrated that the enriched ink was successfully 3D printed at concentrations of 33 and 50 g/100 mL of LA14 callus and 33 g/100 mL of LA16 callus. The feasibility of 3D printing is extremely reduced at higher concentrations of callus material in the ink. The hardness, cohesiveness, and gumminess of the 3D-printed gel with LA16 callus were weakened compared to the gel with LA14 callus. The results of rheological measurements showed that an increase in the content of LA16 callus interfered with the formation of a k-carrageenan gel network, while LA14 callus strengthened the k-carrageenan gel with increasing concentration. Gel samples at different concentrations of LA14 and LA16 calluses formed a spongy network structure, but the number of pores decreased, and their size increased, when the volume fraction occupied by LA14 and LA16 calluses increased. Simple polysaccharides, galacturonic acid residues, and phenolic compounds (PCs) were released from A-FP gels after sequential in vivo oral and in vitro gastrointestinal digestion. PCs were released predominantly in the simulated intestinal and colonic fluids. Thus, incorporating lupin callus into the hydrocolloid ink for food 3D printing can be a promising approach to developing a gelling material with new mechanical, rheological, and functional properties. [ABSTRACT FROM AUTHOR]

[Display omitted] A novel range of microgel particles of different internal cross-linking densities can be created by covalently cross-linking sugar beet pectin (SBP) with the enzyme laccase and mechanically breaking down the subsequent parent hydrogels to sugar beet pectin microgels (SBPMG) via shearing. The bulk rheological properties of suspensions of the different SBPMG are expected to depend on the microgel morphology, elasticity (crosslinking density) and volume fraction respectively. The rheology of both dilute and concentrated dispersions of SBPMG were studied in detail via capillary viscometry and shear rheometry, supplemented by information on particle size and shape from static light scattering, confocal microscopy and electron microscopy. For dilute suspensions of SBPMG , data for viscosity versus effective volume fraction (ɸ eff) falls on a 'master' curve for all 3 types of SBPMG. In the more concentrated regime, the softer microgels allow greater packing and interpenetration and give lower viscosities at the same ɸ eff , but all 3 types of microgel give much higher viscosities than the equivalent concentration of 'non-microgelled' pectin. The firmer microgels can be concentrated to achieve elasticities equivalent to the original parent hydrogel. All SBPMG suspensions were extremely shear thinning but showed virtually no time-dependence. [ABSTRACT FROM AUTHOR]

The phase equilibrium shift caused by changes in polymer-liquid compatibility under the influence of external or internal factors is discussed as the main mechanism of gel formation. Wherein, it is assumed that the gel is a solid, non-flowing soft substance formed due to incomplete phase decomposition of a solution. The sol-gel transition occurs through the intermediate stage of the formation of a viscoelastic yielding medium. The liquid-yielding medium-gel transition results in fundamental changes in the rheological properties of the substance. Therefore, the study of the kinetics of the evolution of rheological properties at various stages of gelation is an important tool for understanding this phenomenon. The review contains a discussion of recent publications and the formulation of some challenging problems. [Display omitted] [ABSTRACT FROM AUTHOR]

In the present study, we used electron beam irradiation (EBI) assisted preparation of citric acid esterification konjac glucomannan (CA-KGM), and the changes in the physicochemical properties and gel properties of KGM were explored. Transparency, thermal stability, and water-binding capacity were enhanced in KGM treated with EBI and citric acid, but the water content, absorption, solubility, molecular weight, and viscosity were decreased. Citric acid reacted with KGM to form CA-KGM, destroying its crystalline region and reducing its relative crystallinity of CA-KGM. The intermolecular interactions of the modified KGM sols were weakened, resulting in a change in their rheological properties. In addition, EBI and citric acid help to inhibit browning, improve texture properties, and enhance water retention of KGM gels. This study provides a new route for the efficient production of low-viscosity KGM, which is conducive to broadening the application scope of KGM in the food, pharmaceutical industry, agriculture, packaging materials, and other field. [ABSTRACT FROM AUTHOR]

In this study, we investigated the effect of electron beam (EB) irradiation-assisted hydrogen peroxide preparation of oxidized KGM (OKGM) on its physicochemical properties. The results showed that treating KGM with EB irradiation and hydrogen peroxide affects the moisture content of KGM, reducing its water absorption, solubility, molecular weight, and viscosity and improving its transparency, thermal stability, and water-binding capacity. The chemical structure of OKGM has changed. There was no significant change in the crystal structure of KGM before and after modification. EB irradiation helps further enhance the effect of oxidative treatment on the rheological properties of KGM. In addition, the browning condition, textural properties, and water retention of the OKGM gels were significantly improved, and the ones pretreated by EB irradiation showed further improvement. In conclusion, EB irradiation can assist hydrogen peroxide in improving the physicochemical properties of KGM, which can further enhance the quality of OKGM. [Display omitted] • EB irradiation is beneficial to enhance the oxidation treatment of KGM by H 2 O 2. • EB irradiation enhances changes in the physical and chemical properties of OKGM. • EB irradiation enhances the effect of H 2 O 2 on the improvement of KGM gel properties. [ABSTRACT FROM AUTHOR]

In redox flow batteries (RFBs), semi-solid flow cells incorporate solid particles in the same medium than the electrolyte in the form of slurry to increase energy efficiency. However, rheological properties of the fluid hosting the solid particles need to favor particle stability and pumping process within the RFB. In this study, the materials used to formulate a gelled polymer electrolyte (GPE), which will be used as a suspending fluid for dense zinc microparticles in a zinc slurry-air RFB, were analyzed. It was found that when using polyacrylic acid and attapulgite gelling agents together, a yield stress behavior was obtained. This satisfactory result was accomplished even in harsh alkaline conditions (pH > 14), representative of the battery operation conditions in which the chemical stability of gelling agents is threatened. Yield stress values were obtained by fitting experimental data to the Herschel-Bulkley model, and results were compared to those obtained by creep tests. Results indicate that the GPEs presented in this study are good candidates to host zinc microparticles for a zinc slurry-air RFB. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Potato starch gel foods are appreciated for their distinctive taste; however, they face challenges such as high paste viscosity, susceptibility to aging, and poor cold-storage stability, limiting their industrial production. This study aimed to enhance potato starch characteristics by investigating the effects of alum, chitosan, carboxymethyl chitosan, and quaternized chitosan on its pasting, rheological, and textural properties. Results revealed that the addition of 1% chitosan, carboxymethyl chitosan, and quaternized chitosan significantly reduced the gelatinization viscosity of potato starch. Moreover, the addition of alum or chitosan provided better shear resistance and reduced shear-thinning behavior. The potato starch gel prepared with chitosan was harder than that prepared with alum. These findings highlight the influential roles of alum, chitosan, and their derivatives in potato starch and provide a theoretical foundation for their application in potato starch gel foods. [Display omitted] • Chitosan modifies rheology and texture properties of potato gels. • Feasibility of chitosan application in potato starch gel food stuffs by comparison with alum. • Determining the impact of modified chitosan on potato starch processing. • Chitosan forms hydrogen bonds; alum forms ionic and hydrogen bonds with potato starch. [ABSTRACT FROM AUTHOR]

Substitution of animal proteins by plant proteins to reduce the consumption of animal proteins is a trend in the field of food consumption. Heteroprotein complex coacervation (HPCC) as a simple and effective technique allows the combination of plant and animal proteins to form novel food materials. In the present work, soy protein isolate (SPI) and type-A gelatin (GA), which are commonly used in food proteins, were used as raw materials to explore their complex coacervation mechanism and the potential of the coacervate to be utilized as a gel. The results showed that the best complex coacervation was achieved at SPI:GA = 1:5, pH = 6.5, and that electrostatic interactions with hydrogen bonding were responsible for this process. The SPI spherical structure was encapsulated in the GA constitutive network structure, and the final polymer morphology took on a spherical-like shape. The final polymer is assembled into a weak gel with a network structure and has favorable viscoelasticity, creep recovery, and thermal stability. These properties of the SPI-GA coacervate may allow its potential use in novel materials for food. [Display omitted] • SPI is wrapped in a GA network to form a spherical coacervate. • Electrostatic interactions and hydrogen bonding were involved in coacervation. • SPI-GA coacervates have potential as a weak gel. • The gel has excellent viscoelasticity, creep recovery and thermal stability. [ABSTRACT FROM AUTHOR]

Whereas water–ethanol hybrid gels present an opportunity to realize aroma enhancement, translating hypothesis into practice is limited by poorly defined viscoelastic characteristics of those gels. In this work, the linear and non-linear rheological properties of water–ethanol hybrid pectin gels (WEPGs) were studied. Those WEPGs are physical gels in nature and the WEPG of 28.6% v/v ethanol differs basically from those of higher ethanol concentrations in the gel strength, resistance to deformation and non-linear properties. The retention of isopentyl acetate of WEPGs is dramatically improved by increasing the ethanol concentration to 33.3% v/v in the co-solvent system, but it is not further improved at 37.5% v/v. The cluster analysis reveals strong positive correlations between the isopentyl acetate release concentration and v3/v1 and absolute value of S/T ratio under 100% strain, suggesting the non-linear rheological responses of WEPGs have to be taken into account for which the enhancement of aroma is desired.

In this study, the influence of levan on the phase behavior and the thermally induced gelation of the mixed β-lactoglobulin—levan gels as a function of polymer content, molecular weight and ionic strength was characterized. For this purpose, rheology was used to study the mechanical properties of the gels and the water binding of the network structure was investigated by time domain nuclear magnetic resonance. Phase behavior and network type were analyzed by optical observation and electron microscopy. Levan enhanced the aggregation and gel formation of β-lg due to segregative forces between the polymer species. Segregation was caused by the excluded volume effect and was more pronounced at lower ionic strength, higher levan contents and higher levan molecular weights. The presence of levan increased the water binding of the gel networks. However, this effect decreased with increasing levan content. At high ionic strength and high levan content, phase separated gels were formed. While segregative forces enhanced network formation, and therefore, increased the gel strength of mixed gels at low ionic strength, levan had also antagonistic effects on the network formation at high ionic strength and high polymer contents. [ABSTRACT FROM AUTHOR]