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Stable water in water (W/W) emulsions of guar rich droplets dispersed in an amylopectin rich continuous phase (G/A) and the inverse (A/G) can be achieved by adding gelatin and inducing microphase separation of the latter by cooling. In this research, the effect of gelatin on the emulsion stability was further studied by storing the emulsions at 10, 20 and 25 °C. The visual aspect, the microstructure, and the viscosity of the emulsions were investigated at different times during storage at different temperatures and pH. It was found that depending on the conditions, the gelatin phase wetted the interface or formed small discrete microdomains that adsorbed at the interface and dispersed in the bulk phases. The observed differences in morphology and stability are related to the interplay of the rates of aggregation, phase separation of gelatin, which itself depend on the gelatin concentration, temperature and pH. Emulsions could be prepared in this manner that were stable for at least one week and remained visually homogeneous. We believe that this is a promising method to stabilize W/W emulsions as long as the components of the emulsion are incompatible with aggregated gelatin. • Water in water (W/W) emulsions were stabilized by adding gelatin. • Microphase separation of gelatin in the W/W emulsions was induced by cooling. • Either a gelatin layer or discrete gelatin domains formed at the W/W interface. • The stability is related to the rates of gelatin aggregation and phase separation. • The stability could be tuned by gelatin concentration, temperature and pH. [ABSTRACT FROM AUTHOR]

Plant protein-based diets (e.g., egg or meat alternatives) have emerged as a promising approach for developing healthy and sustainable food systems. Mayonnaise, a formulated sauce prepared by mixing vegetable oil, egg yolk, vinegar and salt, is probably one of the most widely used condiments in the world today. In this paper, wheat gluten (WG) as an available and low-cost plant protein ingredient was used to prepare and stabilize oil-in-water high internal phase emulsions (HIPEs) as mayonnaise replacers via emulsification–evaporation method. Firstly, WG was dissolved into aqueous acetic acid/ethanol (55/45, v/v, pH 3.0) solution to form phase-separated WG particles, and then HIPEs were prepared through homogenization of high sunflower oil fraction (75 wt%) with WG particles suspension at 80 °C after evaporating ethanol completely. Compared with egg-based mayonnaise, HIPEs (especially for 1.0 wt% WG) exhibited very similar droplet size distribution, rheological behavior, near-perfect thixotropic recovery, and tribological property. These results demonstrated that HIPEs and mayonnaise might have similar sensory property and perceived texture such as creaminess, smoothness, and sliminess. The confocal laser scanning microscopy (CLSM) indicated that close-packed oil droplets could allow them to form homogeneous oil-in-protein network microstructure in HIPEs and mayonnaise, which might contribute to high viscoelasticity, consistency, and correct texture. In addition, thermal stability of HIPEs was much better than that of the mayonnaise. Design and construction of WG-stabilized oil-in-water HIPEs may provide a potential strategy for preparing mayonnaise replacers. [ABSTRACT FROM AUTHOR]

Highlights: [•] WPU surface sizing agents are synthesized with IPDI, PCL, DMPA and EDA. [•] Viscosity increases as NCO/OH molar ratio or DMPA content increases. [•] Particle size increases with NCO/OH molar ratio but decreases with DMPA content. [•] WPU emulsions show different properties as the chemicals-adding sequence varies. [•] The sized papers have much better physical properties than the unsized ones. [Copyright &y& Elsevier]

Highlights: [•] WPU emulsions as surface sizing agents are synthesized with TDI and IPDI. [•] Particle size increases as the NCO/OH and TDI/IPDI molar ratio increase. [•] Viscosity increases as the NCO/OH molar ratio and DMPA content increase. [•] Water resistance increases as the NCO/OH and TDI/IPDI molar ratio increase. [•] The sized papers have much better mechanical properties than the unsized ones. [Copyright &y& Elsevier]

Water-in-water emulsions were formed by mixing aqueous solutions of the neutral polysaccharides guar and amylopectin. The effect of adding gelatin B on emulsions, both of a dispersed guar rich phase in a continuous amylopectin phase and the inverse, were investigated using confocal scanning laser microscopy as a function of the gelatin concentration between 0.25 and 1.5 wt% and the pH between pH 4 and pH 6. Gelatin was found to phase separate upon cooling below about 25 °C in a narrow pH range around pH 5 both in the pure guar phase and in the pure amylopectin phase forming distinct spherical domains. The phase diagram was established as a function of the gelatin concentration and the pH. In the emulsions, the gelatin phase separated first at the interface between the two phases forming a continuous layer at the droplet surface. In some conditions the layer persisted, but in others it broke up into distinct domains. Excess gelatin phase separated in the bulk amylopectin phase, particularly when it was the continuous phase. The gelatin redispersed into the bulk phases when the emulsions were heated to 30 °C. [Display omitted] • Gelatin phase separates during cooling in guar and amylopectin solutions. • Phase separation depends on the pH and is favored by aggregation of gelatin. • W/W/W emulsions can be formed in-situ using guar/amylopectin/gelatin. • Gelatin forms distinct domains or a continuous layer around dispersed droplets. • The formation of the gelatin layer on cooling is reversed by heating. [ABSTRACT FROM AUTHOR]

• PAH/PAA films are coated heavy onto electrospun PAN fibers with layer-by-layer at single pH 5.5. • Heavy LBL-coated membrane exhibits excellent underwater superoleophobicity and self-cleaning property. • The oil stained membrane with extremely high contact areas exhibits high oil removal efficiency. • High flux and efficiency of the oil/water separation could be remained with intermittent pressure. Electrospun polyacrylonitrile fiber membranes (EPFMs) are coated with multilayer films that assembled by layer-by-layer (LBL) technique through alternating deposition of polyallylamine hydrochloride (PAH) and polyacrylic acid (PAA). To obtain the heavy polyelectrolyte (PE) layer consisting of PAH and PAA, single pH value was replaced with alternative pH during LBL processes stabilizing the PAH/PAA layer without significant desorption. The heavy zwitterionic-like LBL coating of PAH/PAA film on the EPFM surface presents complete oil repellency while wetted in water (i.e., underwater superoleophobicity), so that allows to efficiently remove oil stains on dry EPFM by water. Removal of oil staining from a fibrous surface with high contact area demands to build up extremely strong bonding with water in both pristine and oil-wetted states. The PAH/PAA-coated EPFMs exhibit excellent self-cleaning from fibers even already wetted by oil. Generally, there is a maximum permeation volume during oil/water emulsion separation, because the blocked oil accumulates as a hydrophobic layer to block water passing through. These PAH/PAA-coated EPFMs are resilient to oil accumulation with intermittent pressure during the oil/water separation to remain the high permeation flux (over 30,000 L m−2 h−1 bar−1), still an pressing challenge in this area. [ABSTRACT FROM AUTHOR]

Abstract: The interfacial covalent cross-linking of emulsions can greatly enhance their tolerance to environmental stresses, and also contribute to formation of a new class of food products (e.g., oil gel, oil powder, and capsules). Algal oil is rich in ω-3 polyunsaturated fatty acids, while heat treatment makes it particularly susceptible to oxidation. In this study, microfluidization initiated interfacial covalent cross-linking of gliadin particles to stabilize emulsion as a novel technology to facilely construct structured algal oil product without any thermal or chemical treatment. The coarse emulsions with high algal oil volume fraction ( φ oil= 50%) stabilized by acidic gliadin particles were firstly homogenized using IKA homogenizer, and then emulsions were immediately subjected to mild alkaline pH-shifting processes. Finally, microfluidization initiated cross-linking of gliadin via intermolecular disulfide bonds to prepare stable structured emulsions. The droplet size distribution, FTIR, and SDS-PAGE of emulsions clearly verified that cross-linking was initiated by hydrophobic interaction under mild alkaline conditions, and interfacial disulfide cross-linking of gliadins was triggered by microfluidization. The viscoelastic and mechanical properties of emulsions showed homogenization pressure-dependent behavior. In addition, with increasing homogenization pressure, the increased oxidative stability with reduced lipid hydroperoxides and volatile hexanal of emulsions was also observed. Facile construction of cross-linking by microfluidization may provide a novel technology platform for gliadin based delivery system or edible oil structuring with functional characteristics. [ABSTRACT FROM AUTHOR]

This study aimed to decipher the specific role of the interfacial particle network and digestive metabolites within the glycation-tailored interaction mechanism based on the egg white microgel particles (EWGP)-integrated O/W emulsions. Results showed that the bridging extent of the interfacial particle network was significantly reinforced via the increased fibrous aggregates and the improved particles' surface activity (surface hydrophobicity and interface tension) after glycation with d -ribose (<2 wt‰). Besides, the more bridged interfacial network introduced the preferable physicochemical stability, viscoelastic properties, and curcumin retention to emulsions against UV-radiation, in vitro digestion, and storage at 25 °C. Moreover, glycation facilitated the accumulation of larger protein fragments (>10 kDa) and non-ionized long-chain free fatty acids, probably participating in the micellization and secondary stabilization of emulsions with the sustainable bioaccessibility enhancement of curcumin (10–25%) during digestion (1–6 h). Therefore, these findings would be enlightening in intuitively and delicately tailoring the physicochemical stability and delivery properties of emulsion systems according to the characteristics of interfacial particle network and digestive metabolites. Meanwhile, this research would facilitate the direct formulations of native protein matrices (e.g., fresh egg white) in various emulsions-based functional foods for satiation perception and physiological regulation. [Display omitted] • Glycation endowed EWGP with a fibrous cluster array for emulsions stabilization. • Glycation tailored the stabilization and delivery properties of emulsions. • Glycation enhanced the bridging extent of the interfacial network of emulsions. • Interfacial bridging extent was positively correlated with emulsion's stability. • Emulsion's larger digestive metabolites might be vital to its delivery properties. [ABSTRACT FROM AUTHOR]

The rheological behavior of fats or fat replacers is shaped by the interaction among colloidal assemblies giving rise to a specific structural network. We hypothesize that the capillary protein oleogels formation we proposed, in which colloidal protein particles are used as initial building blocks to form space-spanning networks, has linear and nonlinear rheological behaviors similar to fat crystal networks as represented in fractal rheo-mechanical models. Capillary protein oleogels and repulsive high internal-phase emulsions (HIPEs) differing in microstructure categories were therefore assembled for a systematic comparison, as both serve as motivating exemplars for fat replacement. Confocal laser scanning microscopy (CLSM) were employed to distinguish the structural characteristics. By employing both small- (SAOS) and large-amplitude oscillatory shear (LAOS) rheology via Chebyshev polynomial analysis, we examined the linear and nonlinear responses of capillary oleogels and HIPEs under relevant deformations. Differing from the caging effects of droplets within HIPEs, the hierarchical networks with attractive protein particles of capillary oleogels are responsible for interpreting the rheological characteristic parameters in SAOS rheology, and for enhancing resistance to deformation in LAOS due to the coexistence of interparticle interactions and cluster characteristics. The capillary oleogels with attractive protein particles show a similar behavior to that of the fat self-assembled fractal flocs or aggregates in the fractal rheo-mechanical models. These results give us hope that by tailoring the nano- and mesoscale structural organization within a fat replacer in a specific way, there is potential for achieving proper functionality in food products, such as plastic flow behavior. [Display omitted] • Capillary attractive oleogels and repulsive HIPEs were assembled for a systematic comparison in rheology. • Capillary oleogels reveal a two-step yielding signature under deformation. • Intracycle strain stiffening in capillary oleogels results from the coexistence of interparticle interactions and cluster characteristics. • The capillary oleogels show a similar behavior to that of the fat in the fractal rheo-mechanical models. [ABSTRACT FROM AUTHOR]

3D printing has been applied to create nutritious foods with tailored textures for the elderly. However, the edible materials that possess the elastoplastic properties and shear-thinning behavior required for direct-write 3D printing are limited. In this study, we developed a simple approach to fabricate Spirulina emulsion gels as edible 3D printable material by exploiting depletion attraction between emulsion droplets. By controlling the volume ratio of continuous and oil phases, mixing highly viscous Spirulina slurry and vegetable oil could form self-standing oil-in-water emulsion gels with elastoplastic rheological properties. Also, adding food polysaccharides into the continuous phase could act as depletants to drive the formation of emulsion gels. Auto-fluorescence spectroscopy and microscopy were employed to characterize the interfacial protein compositions of the emulsion, showing that phycobilisome (PBS) particles might play a dominant role in the formation of Spirulina emulsions. The depletion attraction could drive the adsorption of PBS particles onto the droplet interface, and the particle-armored droplets in the dispersed phase connected into a percolating droplet cluster, resulting in arrested dynamics and gelation. Overall, this novel approach can be applied by exploiting depletion attraction and opens up possibilities for using high-solids viscous food slurries to produce personalized 3D-printed foods. [Display omitted] • Self-standing emulsion gel is formed by mixing Spirulina slurry with vegetable oil. • PBS particles may play a dominant role in the formation of Spirulina emulsion. • Depletion attraction drives the adsorption of PBS particles onto droplet interface. • Particle-armored droplets are connected into a percolating cluster for gelation. • Polysaccharides as depletants modify the rheological properties of Spirulina emulsion. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effect of dispersion states of azone in gels on the transdermal permeation of levamisole hydrochloride (LH). LH hydroalcoholic gels containing azone of different dispersion states were prepared by varying the contents of azone and Tween 80, and the in vitro transdermal permeation of LH across excised rat skin was evaluated. Depending on the content of azone, mixed solvents, and solubilizer used, azone presented as dissolved molecules, solubilized in micelles, and fine or coarse emulsion droplets in gels. Dramatically increased transdermal permeation of LH within the azone contents between 0.25% and 0.75% indicated high transdermal enhancement efficiency of the molecular or micellar azone, and extra azone that existed as oil droplets did not fully exert transdermal penetration enhancement of LH. Although solubilizer (Tween 80) can greatly increase the solubility of azone, only small amount of Tween 80 (0.5%) in the gel significantly increased the steady-state flux of LH. Addition of extra amount of Tween 80 (>0.5%) reduced the amount of azone distributed in the skin, and thus decreased the transdermal drug permeation. The results partly elucidated the versatile effects of the dispersion states of azone on the transdermal permeation of hydrophilic drug from semisolid gels. [ABSTRACT FROM AUTHOR]

Double emulsion is the most common multiple emulsion with compartmentalized internal structure. It can be used for delivery of both hydrophilic and hydrophobic bioactives and fat reduction in foods. However, conventional approach for stable double emulsion preparation often requires high dosage of synthetic surfactants (e.g., polyglycerol polyricinoleate, PGPR) and complicated two-step emulsification process. Herein, we report a facile approach to create stable double emulsion using particular emulsifier of edible chitosan/soy β-conglycinin (7S) complex nanoparticles via one-step emulsification. By modulating chitosan/7S complex ratio of particles and algal oil content in oil phase, water-in-oil-in-water (W/O/W) Pickering double emulsion was generated in most cases. The dominant mechanism for one-step generation of Pickering double emulsion can be attributed to the polyunsaturated fatty acids (PUFA) in algal oil. The binding of PUFA on particle surface contributes to hydrophobization of the chitosan/7S complex nanoparticles, leading to stabilization of W/O interface. Moreover, stability of the resultant Pickering double emulsions is correlated to particle contact angle. When using nanoparticles with chitosan/7S complex ratio of 1:2 and oil phase containing 40 wt% algal oil, particle contact angle at O/W interface is near 90°, which is the optimum condition to produce highly stable Pickering double emulsion. This facile approach for the fabrication of stable double emulsion is promising for a wide range of applications, particularly in food field. [Display omitted] • A W/O/W Pickering double emulsion was fabricated via one-step emulsification strategy. • Edible chitosan/7S complex particles were used as the interfacial stabilizers. • PUFA in algae oil could modulate particle wettability. • The resultant W/O/W Pickering double emulsion was stable over 50 days. [ABSTRACT FROM AUTHOR]

Herein, we reported a facile method to fabricate ultra-stable, surfactant- and antimicrobial-free Pickering emulsions by designing and modulating emulsions’ interfaces via zein/chitosan colloid particles (ZCCPs). Highly charged ZCCPs with neutral wettability were produced by a facile anti-solvent procedure. The ZCCPs were shown to be effective Pickering emulsifiers because the emulsions formed were highly resistant to coalescence over a 9-month storage period. The ZCCPs were adsorbed irreversibly at the interface during emulsification, forming a hybrid network framework in which zein particles were embedded within the chitosan network, yielding ultra-stable food-grade zein/chitosan colloid particles stabilized Pickering emulsions (ZCCPEs). Moreover, stable surfactant-free oil gels were obtained by a one-step freeze-drying process of the precursor ZCCPEs. This distinctive interfacial architecture accounted for the favourable physical performance, and potentially oxidative and microbial stability of the emulsions and/or oil gels. This work opens up a promising route via a food-grade Pickering emulsion-template approach to transform liquid oil into solid-like fats with zero trans -fat formation. [ABSTRACT FROM AUTHOR]

Abstract: Soybean oil bodies and oleosins are known to be useful in foods and other emulsion systems. The influence of NaCl addition (0–500 mM), thermal processing (30, 60, 90 and 120 °C, 30 min), and freeze-thaw cycling (−20 °C, 24 h/30 °C, 2 h) on the stability of uncoated and ι-carrageenan coated soybean oil body emulsions at pH 3 and 7 was analyzed using particle electrical charge, particle size distribution, creaming stability and confocal laser scanning microscopy measurements. The stability of the uncoated emulsions to NaCl addition depended on pH, which was attributed to electrostatic screening effects. For NaCl, the uncoated emulsions were relatively stable from 0 to 150 mM at pH 3, but aggregated at ≥ 50 mM at pH 7; however, the ι-carrageenan coated emulsions at pH 3 and 7 were stable at all NaCl concentrations. The thermal stability of uncoated and ι-carrageenan coated emulsions may be relative to pH and holding temperature. Both uncoated and ι-carrageenan coated emulsions were stable at pH 7, whereas the uncoated emulsions at pH 3 became unstable when heated above 90 °C, but the ι-carrageenan coated emulsion droplets at pH 3 only extensively coalesced at 120 °C. The ι-carrageenan coated emulsions at pH 3 and 7 exhibited little droplet aggregation after three freeze-thaw cycles in the presence of sucrose. These results suggest that ι-carrageenan coated soybean oil body emulsions have similar or improved stability compared to uncoated emulsions and may be utilized as functional soy products in the food and other industries. [Copyright &y& Elsevier]

[Display omitted] • GA nanofibrils are effective and robust stabilizer to make soft-solid emulsion foams. • Stability and structural properties of emulsion foams were controlled by oil phase polarity. • Emulsion foam with polar castor oil had denser network microstructure, higher mechanical strength, and lower friction coefficients. • Volatile limonene oil weakened structural stability and lubrication ability of emulsion foams. Novel supramolecular nanofibrils assembled from food-grade saponin glycyrrhizic acid (GA) are effective building blocks to make complex multiphase systems, e.g., emulsion foams. In this work, the effects of different oil phases (castor oil, sunflower oil, dodecane, and limonene) on the formation, stability and structural properties of long-lived emulsion foams prepared by GA nanofibrils (GNs) were investigated. The obtained results showed that soft-solid emulsion foams (4 wt% GNs) can be fabricated, independently of oil phase, and their structural properties, viscoelasticity, and tribological properties can be well tuned by oil phase polarity. Compared to the GNs aqueous foams, the presence of jammed emulsion droplets in the liquid channels and at the surfaces of bubbles can provide a higher bubble stability for emulsion foams. For more polar oil phase (castor oil), GNs showed a higher affinity to the oil–water interface with a lower interfacial tension, thus forming smaller oil droplets and bubbles, which leads to the higher mechanical strength, denser network microstructures, and lower friction coefficients of emulsion foams. However, the limonene foam exhibited weak storage stability and rheological properties, as well as the relatively low lubrication, which may be related to the formation of oil droplet aggregates and clusters induced by the volatility of limonene. GN-based emulsion foams are thermoresponsive, independently of oils, and the temperature-switchable process for the destabilization and regeneration of foams can be controlled and repeated. These emulsion foams based on natural saponin nanofibrils with tunable properties have potential sustainable applications in foods, pharmaceuticals, and personal care products. [ABSTRACT FROM AUTHOR]