A review of oil and water retention in emulsified meat products: The mechanisms of gelation and emulsification, the application of multi-layer hydrogels.

Emulsified meat products are key deep-processing products due to unique flavor and high nutritional value. Myosin dissolves, and protein aggregation and heat-induced gelation occur after myosin unfolds and hydrophobic groups are exposed. Myosin could form interfacial protein membranes and wrap fat globules. Emulsified fat globules may be filled in heat-induced gel networks. Therefore, this review intends to discuss the influences of heat-induced gelation and interfacial adsorption behavior on oil and water retention. Firstly, the mechanism of heat-induced gelation was clarified from the perspective of protein conformation and micro-structure. Secondly, the mechanism of emulsification stability and its factors affecting interfacial adsorption were demonstrated as well as limitations and challenges. Finally, the structure characteristics and application of multi-layer hydrogels in the gelation and emulsification were clarified. It could conclude that the characteristic morphology, spatial conformation and structure adjustment affected heat-induced gelation and interfacial adsorption behavior. Spatial conformation and microstructure were adjusted to improve the oil and water retention by pH, ionic strength, amino acid, oil phase characteristic and protein interaction. Multi-layer hydrogels facilitated oil and water retention. The comprehensive review of gelation and emulsification mechanisms could promote the development of meat products and improvement of meat processing technology.

The modulatory roles and regulatory strategy of starch in the textural and rehydration attributes of dried noodle products.

Noodles are popular staple foods globally, and dried noodle products (DNPs) have gained increasing attention due to recent changes in consumer diet behavior. Rapid rehydration and excellent texture quality are the two major demands consumers make of dried noodle products. Unfortunately, these two qualities conflict with each other: the rapid rehydration of DNPs generally requires a loose structure, which is disadvantageous for good texture qualities. This contradiction limits further development of the noodle industry, and overcoming this limitation remains challenging. Starch is the major component of noodles, and it has two main roles in DNPs. It serves as a skeleton for the noodle in gel networks form or acts as a noodle network filler in granule form. In this review, we comprehensively investigate the different roles of starch in DNPs, and propose strategies for balancing the conflicts between texture and rehydration qualities of DNPs by regulating the gel network and granule structure of starch. Current strategies in regulating the gel network mainly focused on the hydrogen bond strength, the orientation degree, and the porosity; while regulating granule structure was generally performed by adjusting the integrity and the gelatinization degree of starch. This review assists in the production of instant dried noodle products with desired qualities, and provides insights into promising enhancements in the quality of starch-based products by manipulating starch structure.

Gel network comprising UV crosslinked PLGA-b-PEG-MA nanoparticles for ibuprofen topical delivery.

Ibuprofen is a non-steroidal anti-inflammatory drug for the treatment of Rheumatoid Arthritis and osteoarthritis. In this study, we prepared topical gel network for enhancement of ibuprofen penetration, maintenance of controlled release and increased patient compliance. Nanoparticles containing ibuprofen were prepared by means of emulsion formation/solvent diffusion method using synthesized copolymer. Nanoparticles were then conjugated with aminoethylmethacrylate, resulting in ibuprofen-loaded nanoparticles in PLGA-b-PEG-MA structure. Ibuprofen-loaded gel networks were developed by crosslinking nanoparticles via UV exposure. Suitability for topical application has been assessed through characterization of particle size, zeta potential, morphology, encapsulation efficiency, in vitro release, cytotoxicity and enhancement of in vitro wound healing. The mean diameter of nanoparticles was measured as 230 ± 20 nm. Gel network formulations with higher particle size (2800 ± 350 nm) and zeta potential (39.8 ± 9.2 mV), depending on conjugation of methacrylate within copolymeric structure, and having encapsulation efficacy of 73.6 ± 2.8% were prepared. The in vitro release of ibuprofen was sustained for more than 7 hours. Gel network improved collagen synthesis, type I collagen mRNA expression and fibrosis in dose dependent manner. Based on this, we can conclude that PLGA-b-PEG gel network might be a promising systems for the local delivery of ibuprofen in RA patients.

Gel network shampoo formulation and hair health benefits.

OBJECTIVE: The objective of this work was to create a shampoo formula that contains a stable ordered gel network structure that delivers fatty alcohols inside hair. METHODS: X-ray diffraction (SAXS and WAXS), SEM and DSC have been used to confirm formation of the ordered Lß gel network with fatty alcohol (cetyl and stearyl alcohols) and an anionic surfactant (SLE1S). Micro-autoradiography and extraction methods using GC-MS were used to confirm penetration of fatty alcohols into hair, and cyclic fatigue testing was used to measure hair strength. RESULTS: In this work, evidence of a stable Lß ordered gel network structure created from cetyl and stearyl alcohols and anionic surfactant (SLE1S) is presented, and this is confirmed via scanning electron microscopy images showing lamella layers and differential scanning calorimetry (DSC) showing new melting peaks vs the starting fatty alcohols. Hair washed for 16 repeat cycles with this shampoo showed penetration of fatty alcohols from the gel network into hair as confirmed by a differential extraction method with GC-MS and by radiolabelling of stearyl alcohol and showing its presence inside hair cross-sections. The gel network role in delivering fatty alcohol inside hair is demonstrated by comparing with a shampoo with added fatty alcohol not in an ordered gel network structure. The hair containing fatty alcohol was measured via the Dia-stron cyclic fatigue instrument and showed a significantly higher number of cycles to break vs control. CONCLUSIONS: The formation of a stable gel network was confirmed in the formulated shampoo, and it was demonstrated that this gel network is important to deliver cetyl and stearyl alcohols into hair. The presence of fatty alcohol inside hair was shown to deliver a hair strength benefit via cyclic fatigue testing.

Oscillatory rheometry for elucidating the influence of non-network biopolymer aggregation on pectin-gelatin composite gels.

Gel networks formed from biopolymers have intrigued rheological interest, especially in the food industry. Despite ubiquitous non-network biopolymer aggregation in real gel food systems, its fundamental rheological implications remain less understood. This study addresses this by preparing pectin-gelatin composite gels with dispersed or aggregated biopolymers and comparatively analyzing viscoelastic responses using rheometry. Subtle discrepancies in non-network biopolymer states were revealed through oscillatory shearing at different frequencies and amplitudes. Biopolymer aggregation in the network notably influenced loss tangent frequency dependency, particularly at high frequencies, elevating I3/I1 values and sensitizing the yield point. Non-network biopolymers weakened Payne effects and gel non-linearity. A combination of strain stiffening and shear thinning nonlinear responses characterized prepared gel systems. Aggregation of pectin and gelatin enhanced shear thinning, while strain stiffening was notable in highly aggregated pectin cases. This study enhances understanding of the link between non-network structural complexity and viscoelastic properties in oscillatory rheometry of food gels.

Effect of starch granule size on the properties of dough and the oil absorption of fried potato crisps.

Starch is a key element in fried potato crisps, however, the effect of starch granule size on oil absorption of the product have yet to be fully investigated. The study explored the impact of starch granule size on both the dough characteristics and oil absorption in potato crisps. The dough composed of small-sized potato granules showed more compact and uniform network system. Additionally, X-ray Microscope analysis showed that potato crisps prepared with small-sized potato granules had limited matrix expansion and fewer pores, cracks, and voids. The small-sized potato and small-sized wheat starches granule addition crisps displayed a significantly greater average cell thickness (52.05 and 53.44 µm) than other samples, while exhibiting notably lower average porosity (61.37 % and 60.28 %) compared to other samples. Results revealed that potato crisps with medium and small potato granules had 12.91 % and 21.92 % lower oil content than those containing large potato starch. Potato crisps with B-type wheat starch showed 16.36 % less oil absorption than those with A-type wheat starch. Small-sized starches significantly influence the dough structure and contribute to the reduction of oil absorption in fried products. The generated insights may provide monitoring indexes for cultivating potato varieties with low oil absorption.

Effect of psyllium husk powder on the gelation behavior, microstructure, and intermolecular interactions in myofibrillar protein gels from Andrias davidianus.

The interaction between proteins and soluble dietary fibers plays a vital role in the development of animal-derived foods. Herein, the effects of different contents (0-3.0%) of round-bracted psyllium husk powder (PHP) on the gelation behavior, microstructure, and intermolecular interactions of Andrias davidianus myofibrillar protein (MP) were investigated. Rheological and chemical forces suggested that PHP (1.5%-2.0%) enhanced the functional properties of MP at low ionic strength, thereby increasing the viscoelasticity of mixed gels. SDS-PAGE revealed that PHP reinforced the cross-linking and aggregation of protein molecules. Circular dichroism spectroscopy, low-field nuclear magnetic resonance, and scanning electron microscopy demonstrated that PHP induced the transformation of α-helix (decreased by 14.85%) to an ordered ß-sheet structure (increased by 81.58%), which was more favorable for the formation of dense network structure and improved (10.53%) the water retention of MP gels. This study provided new insights for PHP to effectively meliorate the heat-induced gelling properties of MP.

Undaria pinnatifida gel inks for food 3D printing are developed based on the colloidal properties of Undaria pinnatifida slurry and protein/colloidal/starch substances.

Currently, people eat Undaria pinnatifida (UP) in a single way, and processing homogeneity is serious. However, UP has not gained any traction in the 3D printing industry to date. This study explored the incorporation of soy protein isolate (SPI), pea protein (PP), xanthan gum (XG), guar gum (GG), corn starch (CS), and potato starch (PS) into UP slurry liquid, the primary component of the study, to formulate a UP gel ink. The UP gel 3D printing ink system based on UP paste was established and characterized. The results show that hydrogen bonds are formed, and three-dimensional gel network structure is formed in all UP gel inks. UP gel inks containing high concentrations of SPI and GG exhibited good texture and rheological qualities and good 3D printing effect, with storage modulus (G') values of 8440.405 ± 3.893 and 8111.730 ± 3.585 Pa. The loss of modulus (G″) values were 1409.107 ± 3.524 and 1071.673 ± 3.669 Pa. Unfortunately, the properties of other UP gel inks are not suitable, resulting in poor 3D printing results. The food 3D printing method developed in this study provides valuable insights for expanding food 3D printing material choices and achieving high-value applications of UP.

Nanorod/nanodisk-integrated liquid crystalline systems for starvation, chemodynamic, and photothermal therapy of cancer.

Indocyanine green (ICG), glucose oxidase (GOx), and copper(II) sulfate (Cu)-installed hybrid gel based on organic nanorod (cellulose nanocrystal [CNC]) and inorganic nanodisk (Laponite [LAP]) was developed to perform a combination of starvation therapy (ST), chemodynamic therapy (CDT), and photothermal therapy (PTT) for localized cancers. A hybrid CNC/LAP network with a nematic phase was designed to enable instant gelation, controlled viscoelasticity, syringe injectability, and longer in vivo retention. Moreover, ICG was introduced into the CNC/LAP gel system to induce hyperthermia of tumor tissue, amplifying the CDT effect; GOx was used for glucose deprivation (related to the Warburg effect); and Cu was introduced for hydroxyl radical generation (based on Fenton-like chemistry) and cellular glutathione (GSH) degradation in cancer cells. The ICG/GOx/Cu-installed CNC/LAP gel in combination with near-infrared (NIR) laser realized improved antiproliferation, cellular reactive oxygen species (ROS) generation, cellular GSH degradation, and apoptosis induction in colorectal cancer (CT-26) cells. In addition, local injection of the CNC/ICG/GOx/Cu/LAP gel into the implanted CT-26 tumor while irradiating it with NIR laser provided strong tumor growth suppression effects. In conclusion, the designed hybrid nanorod/nanodisk gel network can be efficiently applied to the local PTT/ST/CDT of cancer cells.

Entrapment of Glucose Oxidase and Catalase in Silica-Calcium-Alginate Hydrogel Reduces the Release of Gluconic Acid in Must.

Glucose oxidase (GOX) and catalase (CAT) were co-immobilized in silica-calcium-alginate hydrogels to degrade must glucose. The effect of the enzyme dose (1.2-2.4 U/mL), the initial must pH (3.6-4.0), and the incubation temperature (10-20 °C) on the glucose consumption, gluconic acid concentration, pH, and color intensity of Verdejo must was studied by using a Box-Behnken experimental design and comparing free and co-immobilized enzymes. A reduction of up to 37.3 g/L of glucose was observed in co-immobilized enzyme-treated must, corresponding to a decrease in its potential alcohol strength of 2.0% vol. (v/v), while achieving a slight decrease in its pH (between 0.28 and 0.60). This slight acidification was due to a significant reduction in the estimated gluconic acid found in the must (up to 73.7%), likely due to its accumulation inside the capsules. Regarding the operational stability of immobilized enzymes, a gradual reduction in glucose consumption was observed over eight consecutive cycles. Finally, co-immobilized enzymes showed enhanced efficiency over a reaction period of 48 h, with an 87.1% higher ratio of glucose consumed per enzyme dose in the second 24 h period compared with free enzymes. These findings provide valuable insights into the performance of GOX-CAT co-immobilized to produce reduced-alcohol wines, mitigating excessive must acidification.

Effect of cellulose on gel properties of heat-induced low-salt surimi gels: Physicochemical characteristics, water distribution and microstructure.

The processing of surimi products requires the addition of high levels of salt, which makes it a high-salt food that poses a risk to human health. The search for exogenous additives to reduce the salt content of surimi products while ensuring their quality characteristics is crucial. Therefore, the effect of different species of cellulose on enhancing the quality characteristics of low-salt surimi gels was investigated and the best-modified cellulose was identified. Carboxymethyl cellulose (CMC), hydroxypropyl methylcellulose (HPMC), and microcrystalline cellulose (MCC) were selected for this study to compare with high-salt control and low-salt control. The results showed that cellulose could induce conformational transitions of proteins and promote the formation of an ordered and dense surimi gel network and the minimum porosity of 15.935% was obtained in the MCC-treated group. The cellulose-treated group conferred good textural properties to the surimi gels, significantly improved gel strength and water retention capacity (p < 0.05), and reduced the amount of water lost after cooking treatment (p < 0.05). Low-field NMR results showed that cellulose reduced the release of water, converting more free water to immobile water, thus increasing the water proton density. The higher energy storage modulus G' in the presence of cellulose indicated a more stable surimi gel system dominated by springiness. In summary, cellulose could confer better quality characteristics to low-salt surimi gels and MCC performance was superior to other cellulose species. This study helps the understanding of the mechanism of cellulose-surimi action on the development of high-quality low-salt surimi gels.

Formation, stability and the application of Pickering emulsions stabilized with OSA starch/chitosan complexes.

We demonstrated the formation, structure and stability of Pickering emulsions stabilized by octenyl succinic anhydride starch (OSA-S)/chitosan (CS) complexes and explored their potential as templates for porous materials. Sufficient oil fraction (Φ > 50 %) was decisive for stable emulsions, whereas the complex concentration (c) significantly affected the gel network of emulsions. An increase in Φ or c led to tighter droplet arrangement and enhanced network, which improved the self-supporting characteristics and the stability of emulsions. The stacking of OSA-S/CS complexes at the oil-water interface influenced the emulsion properties, forming typical microstructure with small droplets embedded in interstices of large droplets, and bridging flocculation occurred. Porous materials prepared using emulsions (Φ > 75 %) as templates exhibited semi-open structures with pore size and network varying with different Φ or c. There was no structure collapse due to the interconnectivity of complexes. Our work provides comprehensive information on OSA-S/CS complex-stabilized Pickering emulsions.

Silica-Calcium-Alginate Hydrogels for the Co-Immobilization of Glucose Oxidase and Catalase to Reduce the Glucose in Grape Must.

Higher temperatures due to climate change are causing greater sugar production in grapes and more alcoholic wines. The use of glucose oxidase (GOX) and catalase (CAT) in grape must is a biotechnological green strategy to produce reduced-alcohol wines. GOX and CAT were effectively co-immobilized by sol-gel entrapment in silica-calcium-alginate hydrogel capsules. The optimal co-immobilization conditions were achieved at a concentration of the colloidal silica, sodium silicate and sodium alginate of 7.38%, 0.49% and 1.51%, respectively, at pH 6.57. The formation of a porous silica-calcium-alginate structure was confirmed by environmental scanning electron microscopy and the elemental analysis of the hydrogel by X-ray spectroscopy. The immobilized GOX showed a Michaelis-Menten kinetic, while the immobilized CAT fits better to an allosteric model. Immobilization also conferred superior GOX activity at low pH and temperature. The capsules showed a good operational stability, as they could be reused for at least 8 cycles. A substantial reduction of 26.3 g/L of glucose was achieved with encapsulated enzymes, which corresponds to a decrease in potential alcoholic strength of must of about 1.5% vol. These results show that co-immobilized GOX and CAT in silica-calcium-alginate hydrogels is a promising strategy to produce reduced-alcohol wines.

Texturing of Soy Yoghurt Alternatives: Pectin Microgel Particles Serve as Inactive Fillers and Weaken the Soy Protein Gel Structure.

Soy-based yoghurt alternatives were highly requested by consumers over the last few years. However, their texture does not always fulfil consumers' demands as such yoghurt alternatives are often perceived as too firm or too soft, sandy, or fibrous. In order to improve the texture, fibres, for example, in the form of microgel particles (MGP), can be added to the soy matrix. MGP are expected to interact with soy proteins, creating different microstructures and, thus, different gel properties after fermentation. In this study, pectin-based MGP were added in different sizes and concentrations, and the soy gel properties after fermentation were characterised. It was found that the addition of 1 wt.% MGP influenced neither the flow behaviour nor the tribological/lubrication properties of the soy matrix, regardless of the MGP size. However, at higher MGP concentrations (3 and 5 wt.%), the viscosity and yield stress were reduced, the gel strength and cross-linking density decreased, and the water-holding capacity was reduced. At 5 wt.%, strong and visible phase separation occurred. Thus, it can be concluded that apple pectin-based MGP serve as inactive fillers in fermented soy protein matrices. They can, therefore, be used to weaken the gel matrix purposely to create novel microstructures.

Effects of different modified starches and gums on the physicochemical, functional, and microstructural properties of tapioca pearls.

The effects of different modified starch and gums on the physicochemical, functional, and microstructural properties of tapioca pearls were investigated. The addition of starch acetate (SA) and carboxymethylcellulose (CMC) improved the springiness, hardness, cooking properties, and overall acceptability of pearls. Samples added with CMC presented higher peak viscosities, breakdown viscosities, onset gelatinization temperature, and lower enthalpy of gelatinization values compared to control pearls. Furthermore, Rheology and LF-NMR results indicated that all five kinds of modifiers promoted the formation of tighter network structures in products. SEM showed that the addition of SA and hydroxypropyl distarch phosphate (HDP) could fill the voids in the internal gel network of the pearls, thus promoting the formation of a continuous phase network. This study proved SA, HDP, and CMC as modifiers could have tremendous potential to improve the quality of pearls before and after cooking.

Gel network amplifies Nano-Scale adsorption at Solid/Liquid interface to Sub-Millimeter-Scale.

HYPOTHESIS: We have proposed a spreading-flow model of the solvent movement in a gel, which states that the solvent flows along the gel network segment much easier than in any other direction. An excess amount of the solvent component adsorbed on a flat solid surface in a gel will be transferred over the macroscopic gel network by the spreading-flow. Then, by measuring the concentration distribution of each solvent near the solid surface at the sub-millimeter scale, it should be possible to evaluate adsorption occurring on the nanometer scale. EXPERIMENTS: Confocal Raman microscopy was employed to map the concentration distributions of mixed solvents of p-xylene, mesitylene, and octanenitrile gelled by 12-hydroxystearic acid near the atomically flat mica surface. The measured concentration profiles were analyzed by the spreading-flow theory to construct adsorption isotherms. FINDINGS: Nearly all isotherms follow power laws with similar exponents, which is consistent with the van der Waals multilayer adsorption with weak adsorbate-adsorbent interactions. The present study demonstrates the concept of gel network amplification and its usefulness for probing nano-phenomena using macro-technology.

Fabrication and stabilization mechanisms of Pickering emulsions based on gliadin/arabinoxylan complexes.

In the present work, the Pickering emulsions with enhanced oxidation stability were fabricated using gliadin (G)/arabinoxylan nanoparticles (GANPs). The influence of different G/AX ratios on the properties of GANPs and corresponding physicochemical characteristics of Pickering emulsions were investigated. Results indicated that the droplet size and ζ-potential of Pickering emulsions declined with the decrease of G/AX ratios. Pickering emulsion with the smallest G/AX ratio (1:4) exhibited excellent oxidative and coalescence stability due to the formation of viscoelastic gel network, which was supported by confocal laser scanning microscopy (CLSM) images. Furthermore, the increase of salt ions in a lower concentration (0-0.2 M) was conducive to the flocculation of the droplets, while further increasing the NaCl concentration impaired the emulsion stability. Such elements revealed that G/AX complex is a promising stabilizer of Pickering emulsions with prominent antioxidant activity, which have favorable potential applications in protecting the functional properties of polyunsaturated fatty acids (PUFAs).

3D-printing of oxidized starch-based hydrogels with superior hydration properties.

High-hydration hydrogels based on carbohydrate polymers and green preparation methods have attracted intensive research focus recently. Driven by the attractive functions of starch, oxidized maize starch (OMS) was chosen and the related hydrogel (3D-OMS) was constructed by hot-extrusion 3D printing (HE-3DP). Meanwhile, the effect of different OMS concentrations (11 %-19 %) on its printability, structure and hydration properties were systematically investigated. The results showed that the formation of porous structure during HE-3DP environment contributed to rapid water absorption and well water holding capacity of 3D-OMS. Interestingly, as the OMS concentration increased from 11 % to 19 %, the 3D-OMS presented great hydration properties, with its maximum water absorption capacity and water holding capacity reaching 3013.43 % (11-OMS) and 93.53 % (19-OMS), respectively. Among them, 13 % was the best concentration for HE-3DP. Besides, 3D-OMS also exhibited good biodegradability and cytocompatibility. These results demonstrated potential for developing new starch-based biomedical hydrogel with great hydration properties through HE-3DP technology.

Effects of micro-/nano-scaled chicken bones on heat-induced gel properties of low-salt pork batter: Physicochemical characteristics, water distribution, texture, and microstructure.

The effect and mechanism of micro-/nano-scaled (MCB/NCB) chicken bones on improved gel properties of low-salt (0.5%) pork batters (LSPB) were investigated. Results showed that the Ca2+ released from MCB/NCB induced protein conformational transition of LSPB from α-helix and ß-turn to random coil, which facilitated the orderly protein aggregation, resulting in the formation of denser and more uniform gel network. The better-organized gel network not only improved the textural properties and gel strength, but also contributed to the cooking loss reduction, water release decline, water state transition from free water into more immobilized water, and proton density increase, resulting in better sensory attributes. NCB showed more preferable effects on the property improvement of LSPB gels than MCB, because of its smaller particle size, less redness and yellowness, higher dispersibility, and higher Ca2+ release. This study could help promote the high-value utilization of poultry by-product bones and development of low-salt meat products.

Polymer networks produced by marine diatoms in the northern Adriatic sea.

Using high resolution molecular technique of atomic force microscopy, we address the extracellular polymer production of Adriatic diatom Cylindrotheca closterium analyzed at the single cell level and the supramolecular organization of gel phase isolated from the Northern Adriatic macroaggregates. Our results revealed that extracellular polysaccharides freshly produced by marine diatoms can self-assemble directly to form gel network characteristics of the macroscopic gel phase in the natural aquatorium. Based on the experiments performed with isolated polysaccharide fractions of C. closterium and of macroaggregates gel phase, we demonstrated that the polysaccharide self-assembly into gel network can proceed independent of any bacterial mediation or interaction with inorganic particles.