Food-grade emulsion gels are increasingly being used to create food products with innovative properties and functional attributes. However, the rapid expansion of research in this area has outpaced the establishment of standardized methodologies, leading to challenges in reproducibility and cross-study comparability. This review addresses this critical gap by providing a comprehensive set of methodological guidelines for the reliable preparation, characterization, and evaluation of food-grade emulsion gels intended for gastrointestinal-targeted nutrient delivery. Initially, systematic approaches for emulsion gel preparation are reviewed, focusing on formulation parameters and processing conditions that dictate the structure and function of these products. A multi-scale framework for physicochemical characterization of emulsion gels is then presented, encompassing structural, rheological, mechanical, thermal, and fluid-holding properties. Guidelines for testing the performance of emulsion gels under simulated food matrix and storage conditions are then given, including methods to monitor bioactive degradation. Furthermore, best practices for evaluating the gastrointestinal behavior of emulsion gels using standardized in vitro digestion models, and subsequent biological evaluation using cell-based assays, animal models, and human trials are discussed. This review concludes that standardized fabrication, characterization, digestion, and reporting protocols are critical for improving reproducibility and comparability across studies and for advancing food-grade emulsion gels toward reliable functional food applications.
This work evaluated the influence of oil type (sunflower vs. fish oil) and hydroxypropyl methylcellulose (HPMC) concentration on the properties of oleogels obtained by the emulsion-templated method. Oil-in-water emulsions were prepared and air-dried to produce oleogels containing 2.9-5.8% (w/w) HPMC. All oleogels exhibited solid-like behaviour, with viscoelastic moduli increasing with polymer concentration, and showed a high thermal stability. At a comparable HPMC content, fish oil oleogels developed stiffer networks than those obtained with sunflower oil. Texture analysis indicated a linear increase in hardness with HPMC content across both oils, while cohesiveness and adhesiveness were more influenced by oil nature. Oil-binding capacity (OBC) increased markedly with polymer content, exceeding 90% in most systems. However, fish oil oleogels consistently showed lower retention. Colour parameters were only slightly affected by HPMC concentration and were mainly determined by the intrinsic colour of each oil. Overall, both oil type and polymer concentration were shown to be critical factors determining the structural, mechanical, and functional characteristics of HPMC-based oleogels, providing useful information for the development of structured lipid systems as potential substitutes for conventional solid fats.
Photothermal therapy (PTT) has emerged as a promising medical strategy for controlled and targeted drug delivery, due to its ability to trigger rapid release while minimizing damage to surrounding environments. Among different near-infrared (NIR)-responsive nanomaterials, carbon materials are of particular interest due to their multifunctional properties, with graphene oxide (GO) being a powerful photothermal therapy agent that can accelerate stimuli-responsive drug release. Herein, novel stimuli-responsive hydrogels based on polyvinyl alcohol (PVA), gelatin (Gel) and GO, loaded with natural quercetin (Q) were developed and evaluated for their physico-chemical properties, antibacterial and antifungal activities, photothermal Q release, and cellular metabolic activity. Upon NIR laser irradiation, after 10 min, Q was released twice as fast compared to conventional drug release without stimulation. The rapid release of Q by applying light radiation highlights the suitability of these hydrogels for controlled drug delivery applications. The PVA:Gel:GO/Q-hydrogels exhibited strong antimicrobial and antifungal performance (≥90% microbial reduction at higher GO concentrations). Furthermore, a significant reduction in S. aureus adhesion and invasion indicates the sample's potential to mitigate bacterial infections. The PVA:Gel:GO/Q formulations exhibited high biocompatibility in Human Dermal Fibroblasts (HDF), demonstrating that Q improves the safety of PVA:Gel:GO-loaded hydrogels. These results offer promising potential for PVA:Gel:GO/Q hydrogels as advanced materials for photothermal-triggered drug delivery and antimicrobial applications.
In the current study, bioactive-loaded hydrogels were developed with k-carrageenan (1%), and water was replaced with infusions of Urtica dioica L., which modulated the polymer chains to create more robust networks. Urtica dioica L. infusions were obtained with different infusion durations (5 or 10 min) or plant-to-water ratios (0.4, 1, or 2 g/100 mL). The hydrogels were characterized for stability by assessing the syneresis rate and textural and rheological attributes. To elucidate the influence of the infusion on the mechanisms of k-carragenan, temperature ramp tests were applied and FTIR spectra were acquired. Replacing water with Urtica dioica L. infusions for obtaining k-carrageenan hydrogels led to lower syneresis rates (3.34 ± 0.03% and 6.67 ± 0.33%), while the hydrogels showed increased hardness, but lower resilience and cohesiveness. The rheological parameters confirmed the reinforcement; higher G' and gelling temperatures were registered compared to the reference. While FTIR spectra showed that the primary chemical backbone remained intact, the physicochemical changes indicate a strong physical synergy between nettle polyphenols and the κ-carrageenan chains. Of all samples, the highest antioxidant potential value of 94.66% was exhibited by the infusion obtained in 15 min with a ratio of plant material of 2/100 g. These findings demonstrate that plant-to-water ratios and infusion times are critical parameters for tuning the physical properties and biological efficacy of hydrogels for medical or food applications.
Carbon quantum dots (CQDs) and stimuli-responsive hydrogels are advanced functional materials whose hybridization yields CQD-enhanced stimuli-sensitive hydrogels, opening new interdisciplinary avenues for smart material applications. This review systematically summarizes the latest advances in these composites, focusing on synthetic strategies, structure-property modulation mechanisms, and practical applications. Distinct from existing reviews that either investigate CQDs or hydrogels independently or discuss their composites in a single research field, this work features core novelties in integration strategy, application scope and critical analysis: it systematically compares the advantages, limitations and applicable scenarios of three typical CQD-hydrogel integration approaches (physical entrapment, in situ synthesis, covalent conjugation), comprehensively covers the multi-field application progress of the composites and conducts in-depth cross-field analysis of their common scientific issues and technical bottlenecks. By incorporating CQDs, the composites achieve remarkable performance optimizations: 40% improved mechanical toughness, sub-ppm-level heavy metal-sensing sensitivity, and over 80% organic dye photocatalytic degradation efficiency, addressing pure hydrogels' inherent limitations of insufficient strength and single functionality. These enhancements enable sophisticated applications in biomedical field (real-time biosensing, controlled drug delivery), environmental remediation (pollutant detection/degradation), energy storage, and flexible electronics. The synergistic interplay between CQDs and hydrogels facilitates precise single/multi-stimulus responsiveness (pH, temperature, light), a pivotal advance for precision medicine and intelligent environmental monitoring. Despite promising progress, the large-scale practical application of CQD-hydrogel composites still faces prominent challenges: the difficulty in scalable fabrication with the uniform dispersion of CQDs in hydrogel matrices, poor long-term stability of most composites under physiological cyclic stress (service life < 6 months in practical tests), and low accuracy in discriminating multi-stimuli in complex real-world matrices. Future research should prioritize biomass-based eco-friendly CQD synthesis, machine learning-aided multimodal responsive systems, and 3D bioprinting for scalable manufacturing.
Chitin-based hydrogels have emerged as a versatile and sustainable material with significant potential in biomedical, environmental, and energy applications. Derived from the abundant biopolymer chitin, these hydrogels exhibit exceptional biocompatibility, biodegradability, and tunable physicochemical properties. This review highlights advances in chitin-based hydrogels, focusing on solvent systems, crosslinking strategies, and structural modifications to enhance mechanical strength, swelling, and stimuli responsiveness. Key applications include wound healing, drug delivery, tissue engineering, and environmental remediation, where their high-water retention, enzymatic degradability, and eco-friendly nature are particularly advantageous. Furthermore, innovations such as nanoparticle incorporation and chemical derivatization (e.g., carboxymethylation, hydroxypropylation) have expanded their utility in energy devices and smart sensors. Despite these advances, challenges remain in optimizing the energy efficiency of production methods for industrial scalability. This review provides a comprehensive overview of the current state of chitin-based hydrogels, offering insights into future directions for research and development in this promising field.
Konjac glucomannan (KGM) is a naturally derived polysaccharide known for its biocompatibility and gel-forming ability and has gained increasing attention in biomaterial and drug delivery research. However, the rheological behavior of KGM gels at clinically relevant concentrations for periodontal use has not been thoroughly investigated. In this study, KGM gels at 0.8%, 1.0%, and 1.2% (w/v) were prepared and evaluated using oscillatory and steady shear rheology. Rheological analysis revealed increased viscoelastic strength with increasing polymer content, with the 1.2% formulation showing the highest storage modulus, viscosity, and shear stress values across strain, frequency, and temperature ranges. All formulations demonstrated pronounced shear-thinning behavior and dominant elastic characteristics (G' > G″), indicating stable gel network formation and favorable injectability. The viscoelastic profile remained stable near physiological temperature (37 °C), implying that the gel network can preserve mechanical integrity under intraoral conditions. Gamma irradiation at 15 kGy effectively achieved sterility without visible macroscopic instability, although a qualitative reduction in viscosity was observed. Collectively, these findings indicate that increasing KGM concentration improves mechanical robustness and viscoelastic stability, with the 1.2% gel demonstrating the most favorable rheological profile for potential localized periodontal application.
Hybrid supramolecular-nanocomposite hydrogels based on polyethylene glycol (PEG), β-cyclodextrin-adamantane host-guest interactions, and silica nanoparticles represent an important class of hierarchical soft materials with tunable viscoelastic and transport properties. This review critically analyzes recent progress in cyclodextrin-silica hybrid PEG hydrogels, focusing on the mechanistic coupling between stiffness, stress relaxation, and molecular transport arising from the interplay between reversible supramolecular crosslinks and nanoparticle-induced confinement effects. Particular attention is given to how host-guest exchange kinetics regulate dynamic bond rearrangement and affinity-mediated retention of hydrophobic cargo, while silica nanoparticles enhance mechanical reinforcement and modify diffusion pathways through tortuosity and interfacial polymer-particle interactions. The analysis highlights how nanoparticle size, loading level, and surface functionalization influence relaxation spectra and network topology, as well as how environmental stimuli may affect supramolecular bond stability and overall material performance. Comparison with alternative inorganic fillers and mesoporous silica architectures further clarifies the specific advantages of silica in achieving balanced mechanical stability and controlled transport behavior. Overall, current evidence indicates that hybrid CD-silica networks enable partial decoupling of stiffness, relaxation dynamics, and diffusion, although complete independence remains constrained by fundamental polymer physics relationships. These insights support the development of predictive structure-property frameworks for advanced biomedical and controlled release applications.
Sol-gel processing provides an unusually controllable route to nanoporous solids, making silica aerogels the leading reference systems for extremely low thermal conductivity due to their high porosity, nanoscale pore sizes, and tunable solid frameworks. Under near-ambient conditions, thermal transport is multi-scale and multiphase, arising primarily from coupled solid conduction through the skeletal network and gas conduction within the pore space. Accordingly, aerogel design has emphasized suppressing solid-phase transport by reducing network connectivity, increasing tortuosity, and enhancing boundary scattering, while also limiting gaseous conduction through the control of pore size and gas pressure. This critical review provides an integrated overview of these mechanisms and the theory-to-experiment toolbox used to quantify the separate and combined contributions of the solid and gas phases to the effective thermal conductivity. We link key structural and environmental parameters (porosity, pore size distribution, density, backbone morphology, and pressure) to dominant transport regimes and the assumptions embedded in common models. Classical approaches, including effective-medium and percolation-based models, are assessed alongside phonon-scaling descriptions that incorporate characteristic length scales. Particular attention is given to the Knudsen effect and pressure-sensitive gas-conduction models, which are central to interpreting performance at atmospheric conditions and under vacuum or low-pressure operation. This review highlights inconsistencies across datasets and modeling practices, identifies persistent knowledge gaps, and outlines practical directions toward processable structure-property guidelines for manufacturing aerogels with targeted thermal performance, with regard to conduction-dominated heat transport mechanisms.
Aligned CS/Rx aerogels were fabricated by inducing non-directional ice growth (freeze-molding) followed by low-temperature curing, resulting in monoliths with interconnected channels, a high void fraction, and moldability. The swelling index (S%) was calculated to be 1029, the apparent density 0.496 g·cm-3, and the estimated porosity 90% based on micrographic analysis. Aerogels have mechanical behavior Shore A hardness greater than 25. Batch metal removal tests were performed (10 mL, 100 mg·L-1 Cr(VI), 0.19 g adsorbent, 24 h, and pH 5-5.5), and the material achieved 95% metal removal. Additional kinetic and isothermal results were obtained using CS85R15 on a packed column (20 to 140 mg·L-1, 1000 mL Cr(VI), 0.80 g adsorbent, 24 h, and pH 5-5.5). Equilibrium data were consistent with a heterogeneous surface hosting a specific site, as reflected in the joint Freundlich/Langmuir fit (qmax 100.8 mg·g-1 for Langmuir). This confirmed the preservation of chitosan functionalities (-OH/-NH) after processing, while XPS detected chromium on the surface with signals consistent with the partial reduction of Cr(VI) to Cr(III) on the aerogel surface. This highlights the relevance of adsorption-based technologies for water remediation, where high-porosity and low-density materials allow for short diffusion pathways and capture electrostatics by protonated amines and redox conversion of hazardous substances. The soft-cure freeze-molding technique is simple, scalable, and compatible with packed-bed/column operation, providing a material platform for tailoring the microstructure (sheets and channels) and surface chemistry to regenerable sorbents for industrial wastewater treatment.
The rapid emergence of antibiotic-resistant bacteria represents one of the most critical challenges in modern healthcare and has stimulated intense research into alternative antimicrobial strategies. Antibacterial hydrogels have emerged as versatile biomaterials due to their high water content, tunable physicochemical properties, and ability to function as multifunctional platforms for drug delivery and tissue regeneration. This review analyzes recent advances in antibacterial hydrogel systems through a conceptual framework based on three complementary pillars: biological antibacterial agents, inorganic functional components, and structural material engineering. Biological strategies, particularly bacteriophage-based approaches, provide highly specific antibacterial activity capable of targeting multidrug-resistant pathogens and disrupting bacterial biofilms. Inorganic components such as hydroxyapatite nanoparticles contribute additional functionalities including drug adsorption, modulation of the ionic microenvironment, and osteoconductive behavior relevant for bone-related infections. Structural design strategies based on electrospinning enable the fabrication of fibrous architectures that enhance mechanical stability, regulate therapeutic release, and mimic extracellular matrix organization. The integration of these three pillars within multifunctional hydrogel platforms offers promising opportunities for developing advanced antibacterial biomaterials capable of addressing infection control while supporting tissue regeneration.
Bioadhesive materials capable of operating under aqueous conditions are of considerable interest for biomedical and materials science applications. Peptide-based systems represent an attractive platform for such materials due to their structural tunability, inherent biocompatibility, and ability to form supramolecular networks through noncovalent interactions. In this work, a focused library of tyrosine-containing dehydropeptides was designed and synthesized to investigate how molecular architectures influence self-assembly, hydrogel formation and adhesive properties. The peptides were synthesized using a solution-phase Boc strategy and systematically varied with respect to N-terminal protection and C-terminal functionality. The N-protected dehydropeptides formed supramolecular hydrogels through multiple gelation triggers, including pH reduction and heating-cooling cycles. Rheological characterization confirmed the formation of viscoelastic networks with tunable mechanical properties, with storage moduli reaching tens of kilopascals depending on peptide structure. Scanning electron microscopy revealed dense fibrous nanostructures consistent with supramolecular hydrogel formation. The N,C-deprotected dehydropeptides displayed reduced gelation propensity but formed cohesive films with measurable adhesive performance toward hydrophilic substrates. Lap-shear tests demonstrated high shear strengths for the hydrophilic films, highlighting their structural robustness under stress. Overall, this study provides insights into the structure-property relationships governing tyrosine-containing dehydropeptide assemblies and demonstrates their potential as minimalistic building blocks for supramolecular adhesive materials.
This study examined the structural, rheological, and digestive properties of plant-based emulsion-filled gels (EFGs) formulated for dysphagia-friendly nutrition. EFGs were created using a pea protein-κ-carrageenan (PP-κ-CAR) matrix that incorporated oil droplets stabilized by pea protein (EFG-PP), soy lecithin (EFG-PP/LEC), or mono-/diglycerides (EFG-PP/MDG). All formulations met the International Dysphagia Diet Standardisation Initiative Level 6 requirements and showed improved viscoelastic properties compared to the hydrogel control. The interfacial composition determined how the oil droplets influenced the gel network, with droplets in EFG-PP and EFG-PP/MDG contributing to greater reinforcement, whereas those in EFG-PP/LEC resulted in a weaker and more deformable structure. Among the formulations, EFG-PP/LEC demonstrated the most suitable properties for dysphagia management, including the lowest yield stress, softest texture, and highest protein hydrolysis (54%) and free fatty acid release (7.35 µmol/mL). These effects were associated with weaker oil-matrix interactions and greater enzymatic accessibility. The findings highlight the importance of interfacial design in tailoring EFG structure and digestibility for safe, energy-dense diets for individuals with dysphagia.
Peptide-based supramolecular hydrogels have emerged as promising biomaterials due to inherent biocompatibility, tunable self-assembly, and structural similarity to the extracellular matrix. This work describes the design, synthesis and characterization of a library of symmetrical bolaamphiphiles based on dehydropeptides, systematically varying both the dehydroamino acid residue and the linker. Aromatic and aliphatic dicarboxylic acids with distinct rigidities were employed to elucidate their influence on molecular self-assembly, hydrogelation, and functional performance. Hydrogel formation was triggered using a pH-responsive approach, and critical aggregation and gelation concentrations were determined. Morphological analysis by transmission electron microscopy revealed dense fibrillar networks with nanometer-scale fiber diameters, while rheological studies demonstrated viscoelastic behavior, tunable mechanical strength, and, in selected systems, efficient self-healing properties. The incorporation of phenylalanyldehydrophenylalanine significantly enhanced hydrogel formation, highlighting the importance of π-π interactions and hydrophobicity. Biological evaluation using HaCaT keratinocytes confirmed low cytotoxicity across the series. A representative injectable hydrogel exhibited sustained release of the anticancer drug methotrexate, governed predominantly by Fickian diffusion. These results establish clear structure-property-function relationships and demonstrate the potential of symmetrical bolaamphiphilic dehydropeptides as versatile platforms for controlled drug delivery.
The author Anand Vishwas Deshmukh was not included as an author in the original publication [...].
Pesticides are a major cause of water contamination, making this issue a major environmental and public health concern. In this context, the development of advanced and effective remediation materials is needed. In this study, a titanium-functionalized magnetic silica aerogel (AG-Ti@Fe3O4-SA) was successfully prepared via microfluidics and evaluated for water decontamination. The structural and compositional features of the aerogel were determined using XRD, FT-IR, RAMAN, SEM, TEM, BET, and DLS, confirming the formation of the aerogel with dispersed Fe3O4-SA nanoparticles and the successful incorporation of titanium within the aerogel matrix. Regarding decontamination potential, the aerogel was tested against a pesticide mixture, yielding pesticide-dependent removal efficiencies (16-100%). Notably, the aerogel exhibited a high affinity for organophosphorus pesticides and a moderate affinity for polar compounds, whereas bulky hydrophobic pesticides showed lower adsorption. In vitro, the aerogel induced a moderate decrease in HaCaT cell viability after 48 h of exposure, accompanied by a slight increase in lactate dehydrogenase release, while HEK293 cells remained largely unaffected, indicating a cell-type-dependent biological response. Overall, the findings from this screening-level study recommend AG-Ti@Fe3O4-SA aerogel as a promising selective adsorbent for pesticide removal.
Thermal interface materials (TIMs) are essential for addressing heat dissipation challenges in high-performance electronic devices. Among various TIMs, thermal conductive gels exhibit significant potential in high heat flux applications due to their excellent flexibility and superior gap-filling capability. Current research primarily concentrates on the fabrication and performance characterization of novel thermal conductive gels, while comparatively little attention has been devoted to the optimization of processing parameters. Furthermore, existing characterization methods often fail to accurately replicate real-world operating conditions, resulting in discrepancies between laboratory measurements and actual performance. An orthogonal experimental design was adopted to systematically elucidate the influence of filler ratio, wetting time, and silicone oil viscosity on the bonding strength of thermal conductive gels. The filler ratio exerts the most significant influence, followed by silicone oil viscosity and wetting time. Subsequently, the thermal conductivity and thermal resistance of both commercial thermal conductive gels and the as-prepared gels were characterized using the steady-state heat flow method and the double-interface method, respectively. Under the optimized preparation conditions (filler ratio of 88%, silicone oil viscosity of 600 cP, and wetting time of 14 h), the self-developed thermal conductive gel exhibits a thermal conductivity of 3.75 W·m-1·K-1 and a bonding strength of 0.248 MPa, outperforming commercial counterparts and demonstrating promising application potential. It was further concluded, through comparisons of curing rheology and long-term reliability evolution with commercial counterparts, that the self-developed thermal conductive gel possesses enhanced stability and reliability. This study provides a practical reference for the development and engineering application of high thermal conductivity, low thermal resistance gels.
This study investigated the linear and nonlinear viscoelastic properties of cherry Jell-O® samples through oscillatory shear methods including small-amplitude (SAOS), medium-amplitude (MAOS), and large-amplitude (LAOS) experiments. Cherry Jell-O® showed solid-like gel behavior (tanδ < 1) up to γ0:160%. The sample transitioned into nonlinear behavior above γcri: 16% and was classified as type III (weak strain overshoot). Chebyshev coefficients revealed that the samples exhibited strain-stiffening (e3/e1 > 0) and shear-thickening (v3/v1 > 0) intracycle behavior in the nonlinear region. Both elastic and viscous Lissajous-Bowditch curves showed distortions from elliptical trajectories in the nonlinear region. FTIR spectra showed LAOS deformation-induced structural changes, particularly in the Amide I and Amide II regions. Tanδ decreased below 1 upon the removal of the LAOS deformation. These findings showed that although LAOS deformation induced molecular changes in the cherry Jell-O® samples, their elasticity was largely preserved by a strong, resilient network.
Rotator cuff tendon injury (RCTI) is aggravated by the pro-inflammatory milieu elicited by TLR4 and TREM1 signaling. Hence, tendon tissue engineering approaches require considerations that address these inflammatory episodes to benefit active regenerative responses. The objective of this study was to engineer and evaluate the immunocompatibility of a tendon-mimetic hydrogel composed of a chitosan-polyvinyl alcohol (PVA) blend incorporated with Collagen-I and to assess LR12 delivery for addressing TREM1-driven inflammation in RCTI management. A chitosan-PVA-HEMA-Acrylic acid (CPHA) hydrogel was synthesized by blending the linear natural polysaccharide chitosan and linear synthetic polymer PVA in an aqueous phase, followed by incorporation and redox chain growth with HEMA using acrylic acid (AA). Interpenetration of Collagen-I in CPHA yielded the CPHA-C hydrogel. CPHA and CPHA-C hydrogels displayed ample surface functional moieties provided by the co-polymers, exhibited excellent porosity as revealed by SEM imaging (28.65 ± 6.85 and 41.56 ± 18.00, respectively, for CPHA and CPHA-C), and were amphiphilic, as evident by contact angle analysis (~70 for CPHA and CPHA-C). Both hydrogels displayed a progressive release profile for the TREM1-inhibitory peptide LR12 for 7 days, whereas the LR12-loaded CPHA hydrogel exhibited increased TREM1 inhibition in LPS-challenged RAW264.7 macrophages. CPHA and CPHA-C hydrogels were immunocompatible and masked the oxidative damage in RAW264.7 macrophages, as evident by decreased levels of mitochondrial superoxide and ROS. Additionally, the CPHA hydrogel displayed an increased TGFβ/TLR4 ratio (0.24), whereas the CPHA-C (-0.52) system showed a decreased ratio upon exposure to tenocytes and macrophages. Overall, the findings highlight the potential of CPHA and CPHA-C hydrogels as candidates for tendon regenerative applications.
Dysphagia and age-related oral processing limitations are rising with population aging and the growing burden of neurological diseases. Texture-modified diets remain the most common non-pharmacological intervention, yet conventional pureeing and thickening often yield meals with low visual appeal, variable textures, and diluted nutrient density, which contribute to reduced intake and malnutrition risk. Extrusion-based three-dimensional food printing, especially when combined with gel-derived edible inks, offers a digital route to standardize geometry, portioning, and texture while enabling individualized nutrition and sensory design. In the past three years, the field has progressed from simple single-ingredient pastes to engineered soft-matter systems including emulsion gels, high-internal-phase emulsion gels, Pickering-stabilized gels, bigels, and multi-material constructs enabled by dual and coaxial printing. These advances are underpinned by improved rheological windowing, microstructure engineering, and post-print gelation strategies such as ionic crosslinking, thermal setting, enzymatic bridging, and pH-triggered network formation. Meanwhile, dysphagia-oriented product development has matured from "shape recovery" demonstrations toward clinically relevant texture targets, leveraging the IDDSI tests to anchor swallowability. This review synthesizes the recent literature across materials science, food engineering, and clinical nutrition to connect gel microstructure to extrusion performance, post-processing stability, and oral processing outcomes that are relevant to older adults and dysphagia patients. We propose design principles for gel network selection, phase structuring, and process control that simultaneously satisfy print fidelity and swallowing safety targets.