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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]

Here we reported a food-grade Pickering emulsions with pH switchable properties based on soy peptides functionalized calcium phosphate particles (CaP). The nanometer crystalline CaP were synthesized according to the well-established wet chemical precipitation process followed by microfluidization treatment, and functionalized in situ with a pepsin released peptides of soy β -conglycinin. These peptides characterized with a large amount of carboxyl amino acid (Glu and Asp) residues, exhibit high affinity to CaP particles. The decoration of CaP particles with soy peptides enhanced their hydrophobic wettability and electrodynamics properties simultaneously. Hence, the surface modified CaP particles facilitate to construct interfacial crystal architecture and resulting stable Pickering emulsions and gels. The pH triggered switchable properties of the emulsion were established based on the pH-dependent dissolution-recrystallization transition of CaP. Stimuli-responsive Pickering emulsification will not only offer opportunity to create a sustainable way to improve oil and catalyst recovery, but also find interesting applications in food industry for phase release of the functional elements by on-demand strategies. The food grade status of both soy peptides and calcium phosphate might extend their applications for food industry. [ABSTRACT FROM AUTHOR]

In this work, a two-step strategy for fabricating soy protein-based microgel particles was introduced. Gel preparation and homogenization made up the two steps. Microgel particles with nano-scale size were obtained by homogenizing the hydrogel made from soy protein isolate (SPI) with the addition of microbial transglutaminase (MTGase). Colloidal stability, surface hydrophobicity and interfacial properties of the microgel particles were systematically investigated. We confirmed that the microgels had a more rigid conformation when compared to that of SPI, which was attributed to the covalent cross-links inside the microgels formed during gel preparation. By comparison with SPI, the microgel particles with three-phase contact angles more close to 90° exhibited lower surface activity, weaker intermolecular interactions at the interface. We found that most of the microgels adsorbed at the interface and stabilize Pickering type oil-in-water (O/W) emulsion at the pH around the isoelectric point of SPI. The resulting emulsion had good storage stability for 8 weeks. This preparation method, which requires simple operation and common devices, provides a new perspective of fabricating edible functional particulates for food industry. [ABSTRACT FROM AUTHOR]

Flavor is one of the most important criteria for consumer acceptance of food products, especially for low-fat food emulsions. In this study, we prepared structured flavoring oil-in-water (O/W) emulsions based on the crystallization behavior of β -sitosterol (Sito), a functional phytosterol, in the presence of emulsifier (sodium caseinate, SC and octenylsuccinate starch, OSS), These structured emulsions improved colloidal stability during long-term storage and delayed volatiles release under real time dynamic condition. However, the equilibrium static headspace analysis did not show significant differences in the affinities of hydrophobic volatile compounds with pure constitutes of unstructured and structured emulsions. This highlighted the importance of structural properties of the O/W interface in volatile release modulation. A modified gel trapping technology (GTT) combined with polarized light microscopy (PLM) and confocal laser scanning microscope (CLSM) were applied to characterize the microstructure at the oil-water interface, and it clearly showed the formation of a novel Sito crystal/OSA starch complex interface for OSS stabilized structured emulsion. This unique interfacial microstructure might contribute to the strong retention of volatile compounds due to steric barrier and enhanced affinity to those lipophilic volatiles. The formulated flavor emulsion with controlled volatile release profile was successfully prepared by simply blending the unstructured and structured flavoring emulsions. This work provides indications for potential applications of the formulation design in flavor emulsions and phytosterols structured emulsion as novel aroma delivery systems to improve flavor perception. [ABSTRACT FROM AUTHOR]

The sugar beet pectin/soy glycinin (SBP/SG) double network (DN) gel was synthesized by a two-step enzymatic-induced sequential cross-linking strategy. Laccase and microbial transglutaminase (mTGase) were successively employed to the SBP/SG dispersion, so as to induce the formation of the covalent cross-links among the SBP and SG molecules. Uniaxial compression measurements indicated that the DN gels exhibited greater mechanical toughness than the gels with corresponding single network which was only cross-linked by mTGase. Confocal laser scanning microscope (CLSM) and scanning electron microscopy (SEM) observation demonstrated that the phase separation behavior of the two biopolymers at different length scales resulted in the formation of a highly heterogeneous and hierarchical microstructure in the DN gel. The higher structural complexity and mechanical integrity derived from this architecture might be mainly responsible for the enhancement of the gel toughness. A significant decrease of the gel toughness and the disappearance of the hierarchical microstructure were observed in the DN gel prepared by SG and the modified SBP which was subjected to an acidic protease treatment to remove the protein components in SBP. This suggested that the amphiphilic property and the structural heterogeneity of SBP might be the dominant factor in the formation of the unique microstructure in the enzymatic cross-linked protein/polysaccharide DN gel system. These results suggested that the DN principle could widen the texture range of gel-like foods and offer food industry an attractive strategy for developing hierarchical gel architectures via manipulating complex phase separation behavior of protein and polysaccharide. [ABSTRACT FROM AUTHOR]

Abstract: A novel, safe and rapid method for preparing soy protein-based porous hydrogel was described in this work. The porous hydrogel was synthesized by high speed homogenizing in the presence of microbial transglutaminase (MTGase) that catalyzed the cross-linking of the proteins. Computed microtomography (μCT) was used to characterize the porous structure of the formed gels. The extent of cross-linking and mechanical properties of the hydrogel were also evaluated. The influence of MTGase addition, homogenizing speed and soy protein isolates (SPI) dispersion pre-heating temperature on the porosity and mechanical properties of the hydrogel was investigated. The amount of MTGase, which determined the degree of cross-linking, gelation time and gel strength, played a critical role in preparation. With this method, soy protein porous hydrogel with controllable porous architecture was able to be prepared in a fast and simple way. This porous structure provided a special texture and some potential applications such as nutrients and flavors carrier for the hydrogel. [Copyright &y& Elsevier]

Abstract: In this work, a novel two-step method for preparing food globular protein-based hydrogel with transparent appearance and stable network was described. First, soy glycinin dispersion (6% w/v) was heated at 95 °C for 30 min in order to obtain partial unfolding conformation and expose more residues for the following enzymatic cross-linking. An anionic polysaccharide, dextran sulfate (DS), was added before glycinin was heated, forming highly charged complexes with glycinin and maintaining the transparency of the dispersion. Microbial transglutaminase (MTGase) was introduced for gelation, creating a covalent network. Transparent cold-set hydrogels could be obtained when the weight ratio of DS to glycinin was over 1/200. It was found that larger amounts of DS and lower ionic strength were favorable for increasing the transparency of the gels. At pH 7.0, effects of DS amounts and ionic strength on the rheological and mechanical properties of the hydrogels were investigated. Hydrogels with distinctive textural properties could be obtained by different combinations of DS amount and ionic strength. Scanning electron microscopy observation indicated that the addition of DS could promote the formation of regular and stable gel network. [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]

Random aggregation character and beany flavor limit the application of soy protein products in drinkable and semi-solid protein-rich products that taste smooth and soft. A co-protein strategy was employed to prepare soy protein-based microparticles with improved heat stability and weak gelation ability in this work. Egg white protein (EWP), which served as a free sulfhydryl (SH) donor, was mixed with soy protein isolate (SPI). Microparticulation and spray drying were successively conducted on the mixture, and roughly spherical composite microparticles were obtained. The addition of EWP significantly increased the number of intermolecular disulfide linkage inside the microparticles, which was verified by the determinations of their free SH and cystine levels as well as their extractability in sodium dodecyl sulfate-containing buffers. When re-dispersed in deionized water at a neutral pH condition, most of the composite particles had a diameter ranged from 2 to 20 μm. Their size distribution analysis suggested that there was no significant particle aggregation occurred after this dispersion was heated at 95 °C for 30 min. The frequency-dependent storage moduli indicated that this heated dispersion with a protein concentration of 12 wt% was still a viscous liquid. The tribological test suggested that this dispersion also provided better lubrication for the contact between the soft rubber surfaces. The gas chromatography-mass spectrometry analysis showed that the flavor volatiles content in the composite microparticles was much lower than that in SPI. This might provide another perspective for preparing novel soy protein-based ingredients with improved functionalities for protein-rich foods. Image 1072 • A co-protein strategy was employed to prepare soy protein-based microparticles. • Mixture of egg white protein and soy protein was subjected to microparticulation. • More disulfide linkages formed inside the composite microparticles. • Composite particles had improved heat stability and weak gelation ability. • Flavor volatile content in the microparticles was significantly reduced. [ABSTRACT FROM AUTHOR]

Excess consumption of animal meat is negatively associated with human health benefits and environmental sustainability. In recent years, many academic institutions, large food manufacturers, and start-ups have attached great importance to the development of meat analogs, but there is still a major technical challenge to developing products with wide acceptance by consumers. To mimic the juiciness in meat products derived from the phase transition of animal fats, oleogel, in which vegetable oil was structured by a network made up of whey protein isolates (WPI) and water, was prepared in this work. It was integrated into a soybean protein gel induced by transglutaminase to set up a composite gel model for meat analog. The heated composite gels were then subjected to in vivo and in vitro oral processing experiments. The proportion of oil released from the gel matrix, the tribological properties of the simulated bolus, and the sensory attribute evaluation were investigated. The results indicated that the addition of oleogel significantly enhanced the oil release and improve the fat-related sensory attributes. The transition of the microstructure in the oleogel caused by heating and shearing might be responsible for its oil-release behavior. However, this effect could not be observed in the composite gel with the addition of emulsion gel. It suggested that the oleogel prepared in this work might be a potential component for improving the juiciness attributes of the meat analog, providing a new idea for elevating the quality and acceptability of the meat analog. [Display omitted] • A good idea was provided to developing meat analogs with wide acceptance. • Juiciness was firstly used to improve oral texture perception in meat analogs. • The oil release behavior was investigated using in vitro and in vivo methods. • Nearly 50% of the oil was released from meat analogs with the addition of oleogel. • The released oil improved the lubrication and fat-related sensory attributes. [ABSTRACT FROM AUTHOR]

Abstract Soy protein isolate (SPI, 1–4 wt%) was heated by conventional heat treatment (90 °C) and subcritical water treatment (SW, 120 °C). The aggregation degree, surface hydrophobicity, interfacial adsorption behaviors, foaming and emulsifying properties were characterized to evaluate the effects of aggregation degree on the foaming and emulsifying properties of proteins. SW treatment induced the formation of larger soluble aggregates dominated by intermolecular hydrophobic interactions. Compared to native SPI and SPI heated at 90 °C (SPI90), SW-treated SPI showed a higher surface activity at the air-water and oil-water interface due to lower aggregation degree and more flexible conformation. Obvious improvements of foam capacity and stability may be attributed to the formation of an interfacial layer with higher macromolecule interactions. Moreover, SW treatment effectively improved storage and freeze-thaw stability against emulsion coalescence due to the formation of a thicker multilayer, although higher flocculation degree was observed. These results suggest that SW treatment could be an effective technique to modify structural and functional properties of soy protein for stable foam and emulsion foods. Graphical abstract Image Highlights • Heating temperature and protein concentration affect protein aggregation behaviors. • Subcritical water-treated soy protein exhibited a higher surface activity. • The formation of gel-like interfacial layer improved foam capacity and stability. • A thicker multilayer provided an protection for oil droplets against coalescence. [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]

Interparticle forces that govern the assembly of particles adsorbed at fluid interfaces determine the rheology and microstructure of particle laden interface. In this study, natural small molecule, tannic acid (TA), was used to modify particle-particle interactions and assembly behaviors of food grade hydrophobic protein particle (zein nanoparticle) at air-water interface. For bare zein particle (ZP), the rapid adsorption and high interparticle forces led to the low coverage and formation of large ZP aggregates at the interface. The hydrogen-bonding of TA weakened the particle hydrophobicity and thus interparticle forces at fluid interfaces. Therefore, the adsorption process and assembly rate of ZTP at the interface obviously reduced, which also provided enough time for ZTP to rearrange into orderly interfacial networks. Furthermore, the Lissajous plots of surface pressure versus deformation are used to understand the surface rheological response to large mechanical deformation in terms of interfacial microstructure. The rheological response of interface stabilized by ZTP showed strain hardening during extension and strain softening during compression. These findings indicate that the interfacial rheology and microstructure of zein particle-laden interface can be tuned by changing the TA content. [ABSTRACT FROM AUTHOR]

Structuring liquid oils into solid fats without partially hydrogenated oils (PHOs) can decrease trans fats intakes, now become emergent technical challenge and demanding task. This paper presented a simple and economic strategy for structuring liquid oils by using wheat gluten (WG) stabilized oil-in-glycerol emulsion gels. The WG was firstly dissolved in edible glycerol at 130 °C, and emulsion gels were then prepared through homogenization of high corn oil volume fraction (φ oil = 60%) with the glycerol suspension of WG at room temperature. Both WG and edible glycerol are widely available low-cost food ingredients. Confocal laser scanning microscopy (CLSM) images clearly indicated the formation of WG protein percolating oil-in-glycerol emulsion gels. Gel trapping technology (GTT) and interfacial tension decay were applied to characterize the adsorbed monolayer and the absorption behavior of wheat proteins (WG, gliadin-rich fraction, and glutenin-rich fraction) at the oil-glycerol interface. The results revealed that gliadin played a dominant role in the formation of interfacial architecture, but the synergistic interfacial effects of glutenin and gliadin were also observed. The WG based emulsion gels exhibited higher elastic, shear thinning behavior, good thixotropic recovery, and heat stability, which showed the potential application in alternatives for plastic fat, such as spreads, and other delivery systems for functional ingredients without PHOs. [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 extremely high requirements for the design of food matrices with suitable rheological properties. Starch exhibits considerable potential as a material for 3D printing. However, there is limited research available on the direct fabrication of oleogels using starch granules as building blocks. In this study, we developed a simple approach to fabricate plant-based oleogels as edible 3D printable materials by exploiting capillary forces between starch granules. When a small amount of water (less than 5 wt%) was added to starch granules dispersed in an oil phase, a pendular bridging network was formed between the starch granules. The rheological properties of the starch-oil suspension were significantly changed, transitioning it from a fluid-like to a gel-like state. The rheological properties of the oleogel could be altered by varying the starch granule volume fraction, the amount of water added, the structure of starch granules, and the oil-water interfacial tension. Confocal laser microscopy imaging demonstrated that starch granule oleogels exhibit three distinct structural states: pendular state, pendular bridge network, and capillary aggregation. Furthermore, the presence of water was identified as a liquid bridge between starch granules. Additionally, starch granule oleogels exhibited excellent thermal stability and freeze-thaw stability. Overall, this approach enhances the feasibility of preparing starch oleogels and provides valuable insights for the personalized 3D printing of oleogels. [Display omitted] • Starch granule based oleogels were successfully prepared through capillary attraction. • Untreated native starch granules were firstly used in the preparation of oleogels. • The oleogel network was formed by granules connected through meniscus bridges. • Modulating rheological properties of the oleogel via added water or starch content. [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]

Plant protein-based hydrogels have enormous potential applications, and their great functional properties and sustainability are considered the best alternatives to reduce the environmental burden of animal protein resources. However, heat-induced plant protein-based hydrogels often exhibit a rough and opaque network structure, limiting their application in various scenarios where gel transparency is crucial. In this study, transparent hydrogels were successfully prepared using deamidated soy protein isolate (SPI) modified by protein-glutaminase (PG). Compared with the non-transparent SPI hydrogel, the deamidated SPI hydrogel possessed a soft and intricate chain-like network, exhibiting excellent light transmittance and certain mechanical strength. The results indicated that deamidation treatment unfolded the structure of SPI, shifting the protein conformation from ordered to disordered, and leading to the transformation of large insoluble protein aggregates into small soluble aggregates. In addition, deamidation treatment effectively inhibited the thermal aggregation rate and aggregation counts of SPI. This was attributed to the conversion of glutamine to glutamic acid, which enhanced the electrostatic repulsion between protein molecules. The present work offers a promising approach for preparing highly transparent plant protein-based hydrogels, which are conducive to developing the next generation of plant protein-based functional materials to replace existing petroleum-based materials. [Display omitted] • Transparent soy protein hydrogel is successfully prepared without the addition of any gelling agents. • The deamidation reaction depolymerizes the insoluble soy protein aggregates. • Deamidation treatment inhibits the thermal aggregation of soybean protein. • Deamidated soy protein exhibits a more flexible gel network structure. [ABSTRACT FROM AUTHOR]

Edible protein-based oleogels have garnered extensive attention in food formulation, driven by the desire for enhanced nutritional profiles and improved texture perception. This is facilitated by the nutritional value of the starting ingredient proteins, coupled with high consumer acceptance. However, there exists limited knowledge regarding the connection between the microstructural properties of gels and their macroscopic rheological properties, especially concerning their potential as fat replacers in food products. The present study reveals a simple means of modulating the microstructural properties and macroscopic mechanical features of capillary whey protein oleogels, as well as their aesthetic properties. This is achieved by using whey protein variants with diverse morphologies, such as fibers, particles, and fractal clusters, or by varying the water fraction (s) and the protein concentration (φ) in the formula. Rheological scaling properties and confocal laser scanning microscopy (CLSM) were employed to investigate the structural contribution of protein particles within the gel network. Furthermore, the study explores the practical applications of the derived oleogels, particularly in terms of spreadability or shortening as a potential alternative to margarine, within real food matrices. The spreadability of capillary oleogels with a protein concentration (φ) at 0.16 and 0.18 was comparable to that of commercial margarine. Meanwhile, the capillary oleogel-cake exhibited similarity to the margarine cake in textural parameters and sensory acceptability. This suggests that these capillary whey protein oleogels hold promise for applications in bakery products as margarine alternatives with low levels of saturated/ trans -fat content. [Display omitted] • Capillary oleogels can be formed by using whey protein variants with diverse morphologies. • Capillary oleogels fabricated with different particle shape have diverse mechanical features and aesthetic properties. • The microstructural of capillary oleogels can be tuned by adjusting the water fraction or the protein concentration. • Capillary whey protein oleogels hold promise for applications as margarine alternatives. [ABSTRACT FROM AUTHOR]

Salt reduction strategies in liquid foods remains a significant challenge. The oral perception of Na+ is strongly dependent on its salivary penetration and mucosal adsorption. To understand the mechanism of Na+ saltiness enhancement modulated by polysaccharide, protease hydrolysis (trypsin and acid protease) was used to modify the molecular conformation of Gum Arabic (GA), a highly branched polyanionic polysaccharide. The salivary permeation, mucosal retention in mucin layer, and salty taste of Na+ were investigated. Saltiness-enhanced effect of GA is strongly influenced by its molecular conformation. Compared to native GA, protease-hydrolyzed GA exhibited a higher saltiness-enhanced effect due to more rapid Na+ diffusion in saliva and stronger mucosal retention. Protease-hydrolyzed GA, especially acid protease-hydrolyzed GA (GA-AcPr), exhibited lower zeta potential (from original −22.5 to −27.96) and stronger Na+ loading capacity. The obvious decreases in molecular weight (M w) and the radius of gyration (R g) were observed for trypsin-hydrolyzed GA (GA-Trypsin), which may be responsible for the higher Na+ diffusion effect of GA-saliva solution due to decreased molecule twine around each other. GA-AcPr exhibited looser and highly branched conformation, as evidenced by a more pronounced "U-shaped" curve and higher R g /R h. Moreover, Quartz crystal microbalance with dissipation (QCM-D) results verified stronger affinity between GA-AcPr and mucin, indicating that the saltiness-enhanced effect of GA-AcPr may be mainly achieved by increasing adhesive retention of Na+. These results would be useful to better understand the structure-function relationship of polysaccharides and the taste perception of Na+. [Display omitted] • Proteolytic-hydrolyzed GA improved saltiness perception of Na+. • Higher saltiness perception was associated with increased diffusion rate of Na+. • Enhanced Na + retention in the mucosa leads to an improved perception of saltiness. • Saltiness-enhanced effect of GA is strongly influenced by molecular conformation. [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]

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]

Soybean soluble polysaccharide (SSPS) is anionic polysaccharide extracted from the by-product of isolated soy protein production. In this study, a simple and eco-friendly procedure had been developed to prepare high-molecular-weight octenyl succinic esters of SSPS (OSA-SSPS) via the esterification between SSPS and octenyl succinic anhydride (OSA). The absolute molecular weights of OSA-SSPS and SSPS were 620 kDa and 53 kDa, respectively. OSA-SSPS had some similar properties to SSPS, such as microstructure and viscosity of 1 wt% concentration. However, compared to SSPS, OSA-SSPS showed different milk protein stabilization properties. The stabilizing behavior of OSA-SSPS was better than that of SSPS at pH range of 3.8–4.6, and poorer at pH 3.6. The model mixture of OSA-SSPS had smaller particle sizes at pH range of 3.8–4.6 and larger absolute negative charges at pH 2.0–10.0. In addition, from the molecular diameter measured by DLS and AFM image, the surface concentration of OSA-SSPS was larger than that of SSPS, which indicated that the thicker OSA-SSPS layer produces larger steric repulsion to milk protein particles. The mechanism for the greater ability of OSA-SSPS to stabilize milk proteins was proposed on the basis of the results discussed in this research. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate for the first time the use of gliadin colloid particles (GCPs) as an effective particulate stabilizer of oil-in-water emulsions of natural oils and water. For this purpose, we fabricated GCPs through a facile anti-solvent precipitation procedure and demonstrated their uses in the formation of Pickering emulsions as well as Pickering high internal phase emulsions (HIPEs). We found that unmodified GCPs can produce stable, surfactant-free o/w emulsions with microscale droplet sizes under experimental mixing conditions at pH 4 and above. In contrast, the emulsions were not stable against coalescence at ∼pH 3.0. The microstructures, e.g., interfacial framework, GCPs partition between the continuous phase and interfacial region, and state of the droplets, of Pickering emulsions as a function of pH were visualized by optical microscopy and confocal laser scanning microscopy (CLSM), confirming that in addition to Pickering stabilization, the GCPs-based network and/or dispersed droplets-based network also contributed to the stabilization of the emulsions, in a pH-dependent manner. Clear correlations exist between colloid properties of the GCPs dispersions and the emulsion characteristics. Interestingly, stable surfactant-free Pickering HIPEs were fabricated by a facile shearing emulsification. This study opens a promising route based on Pickering HIPEs to transform liquid oils into viscoelastic emulsion gels with zero trans-fat and less saturated fat. The Pickering HIPEs possess promising potentials to replace solid fat in food formulations, which outline new directions for future fundamental research. [ABSTRACT FROM AUTHOR]

In this work, we developed multilayer bacterial cellulose (BC)-zein films based on the strong BC film as the outer layers and the electrospun zein fibers as the inner layer, to improve the water resistance properties of hydrophilic BC films. The water resistance properties were evaluated by dynamic water absorption measurement and mung beans storage test. The obtained results showed that the incorporation of electrospun zein fibers made the relatively thin and flexible multilayer films become stiffer, while the zein interlayer did not markedly affect the thermal stability and surface properties of films. Compared to pure BC films, the BC-zein films exhibited significantly better water resistance properties, especially under longer zein deposition time (90 and 120 min). This improvement could be mainly due to the inherent hydrophobicity of zein protein. These findings provide the possibility of adopting a multilayer film strategy for the development of BC packaging films with enhanced water resistance properties by incorporating a high barrier interlayer of electrospun zein fibers. [ABSTRACT FROM AUTHOR]

Colloidal complexation of zein hydrolysate (ZH) with tannic acid (TA) and the possibility of using the ZH-TA complex to construct a nanoemulsion system for alga oil delivery were investigated. Turbidity and fluorescence titration measurements demonstrated the complexation of ZH with TA, which leads to the formation of ZH-TA complex. Isothermal titration calorimetry further confirmed the complexation between ZH and TA was driven by the non-covalent interaction (e.g. hydrophobic interaction and hydrogen bonding). The emulsifying activity of ZH was considerably improved after the complexation with TA, which was responsible for the fabrication of alga oil nanoemulsions ( d = 120 nm). The emulsions stabilized by the ZH-TA complex showed a remarkable physical stability and high alga oil encapsulation efficiency. More importantly, the complexation of ZH with TA also endowed ZH-TA complex with high antioxidative properties. The alga oil nanoemulsions stabilized by ZH-TA complex showed an increased oxidative stability with reduced lipid hydroperoxides and volatile hexanal compared with that of stabilized by ZH alone. This study demonstrated that ZH-TA complex could be employed as an emulsifier in constructing a physical stable nanoemulsion delivery system, and opens up the possibility of utilizing peptides–polyphenol complex as efficient emulsifiers to improve the oxidative stability of O/W nanoemulsions. [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]