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BACKGROUND: In order to study the effect of adsorption of surfactant at the two interfacial layers on emulsion stability, the kinetically stable water‐in‐oil‐in‐water (W/O/W) emulsion carriers were prepared using polyglycerol polyricinoleate (PGPR) and gum arabic (GA) as emulsifiers. The relationship between the adsorption of the surfactant and the stability mechanism of the emulsions was elucidated. RESULTS: When the contents of PGPR and GA were low, the interfaces between oil and the inner and outer water phases, respectively, could not be completely covered. However, when the concentration of PGPR was higher than 60 g kg−1, the excess PGPR was adsorbed on the interface between the oil phase and the outer water phase. When the concentration of GA reached 80 g kg−1, more GA was adsorbed to the oil‐in‐water interface. Moreover, the presence of PGPR on the interface could reduce the adsorption capacity of GA. Two types of kinetically stable emulsions were obtained by optimizing the interface composition (60 g kg−1 GA/80 g kg−1 PGPR and 60 g kg−1 PGPR/80 g kg−1 GA). The kinetically stable W/O/W emulsions prepared in this study were successfully used to encapsulate a hydrophilic vitamin (vitamin B12) with an encapsulation efficiency (EE) of 80% and release efficiency (RE) of 95%. The interfacial adsorption GA can accelerate the hydrolysis of fat. CONCLUSION: Overall, this study provides a new strategy for the preparation of W/O/W emulsions, which might be beneficial for application in food, cosmetic, chemical, and pharmaceutical industries. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

• Polyglycerol polyricinoleate affects stability by changing the viscosity and interfacial layer of emulsion. • The effects of different homogenization methods on the microstructure and stability of emulsion were analyzed. • The microscopic motion and diffusion of emulsion droplets were analyzed by the diffusing wave spectroscopy (DWS). • The droplet coalescence and Ostwald ripening curing behavior of water-in-oil emulsion during storage were analyzed. The aim of this study was to investigate the effect of the preparation methods and the concentration of polyglycerol polyricinoleate (PGPR) on the stability of the water-in-oil (W/O) emulsion. By comparing two different emulsions preparation methods, high-speed shear (16000 rpm) and high-pressure homogenization. We were found that high-speed shear treatment could reduce the particle size of the emulsion more effectively, thus significantly improving the stability of the emulsion. In addition, the effect of PGPR concentration on the stabilization mechanism of the emulsion was also discussed. The results showed that when the concentration of the PGPR was increased from 2 % to 6 %, it effectively prevented emulsion droplets polymerization and improved the stability of the emulsion. When the PGPR concentration was further increased to 10 %, the physical properties of the emulsion were mainly characterized by an increase in viscosity, which further enhanced the stability of the emulsion. In experiments involving the encapsulation of VB12, the encapsulation efficiency (EE) exceeded 95 %, and the retention efficiency (RE) exceeded 85 % even after 21 days of storage, demonstrating excellent stability. This study provided new insights into the preparation of stable water–oil emulsions, particularly regarding the efficient encapsulation and long-term stability of nutrients, and held significant application value for the food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

The characterization of emulsions covered with cellulose particles prepared under varying hydrolysis durations investigated. The results showed that with the increasing hydrolysis durations, the particle size distribution profiles of emulsion stabilized cellulose particles shifted to a lower particle size. This was primarily because at longer hydrolysis durations, a larger number of particles per interfacial area were expected to be adsorbed at the interface of oil droplets. At hydrolysis durations of 6 and 10 h, the mean particle diameter of emulsion had an increase of 20–30 nm after 7 days and showed good stability with storage time, which can be attributed to a relatively thick interface layer. Emulsions stabilized by cellulose particles prepared at hydrolysis durations of 6 and 10 h showed good stability against changes in pH and NaCl concentration. These results can be useful for designing food and beverage Pickering emulsions with the improved bioavailability of functional nutrients. [ABSTRACT FROM AUTHOR]

Axiolitic shape nanocellulose particles were prepared using a combined mixed acid hydrolysis and ultrasonic treatment. The crystallinity, morphology and stability properties of cellulose were characterized to investigate the mechanism of nanocellulose formation and stability. It was found the hydrodynamic radius decreased from 205 nm to 89 nm, and the crystallinity index of the nanocellulose increased from 62.90% to 72.31% with an increase in hydrolysis time from 2 to 10 h. Sulfate esters and sulfonate group were present in the nanocellulose, and released more C OH groups after hydrolysis. The ζ-potential of cellulose decreased from −11.5 to −43.8 mV after 10 h of hydrolysis. These results illustrated the amorphous characteristic of cellulose was removed after acid hydrolysis and ultrasonic treatment. The higher ζ-potential and relatively small cellulose particles caused a more stable suspension, suggesting that electrostatic interactions played an important role in maintaining the stability and dispersibility of the nanocellulose particles. [ABSTRACT FROM AUTHOR]

In this work, three methods were used for preparation of the emulsion. The mean particle diameter, ζ-potential, microstructure and stability of the emulsions coated by ovalbumin (OVA) and gum arabic (GA) were evaluated. The complexes (OVA/GA) and multilayer (OVA-GA) emulsions showed smaller droplet diameter (about 330 nm) above pH 3.3 and had a relatively good storage stability compared to the multilayer (GA-OVA) emulsion. Meanwhile, different stabilization mechanisms were identified. In the complexes (OVA/GA) emulsions, the OVA and GA formed complexes firstly that created an interface layer on the surface of the droplets. For the multilayer (OVA-GA) emulsion, the OVA adsorbed on the surface of the droplets, and then GA formed a double-layer structure by electrostatic interaction between the GA and the OVA. The multilayer (GA-OVA) emulsions showed a larger mean particle diameter due to the poor adsorption capacity of the GA compared with OVA. All emulsions revealed good thermal stability and no obvious change was observed. The experimental results demonstrated that the OVA/GA complexes could be used to prepare stable emulsion structures, which may be useful in the beverage industry. [ABSTRACT FROM AUTHOR]

Soy polysaccharide is a new source of hydrocolloids that demonstrated some unique functions, such as improving the emulsifying property of proteins. Citral is an essential oil that shows promise as an alternative to antibiotics for livestock such as chickens. However, lack of effective delivery methods has limited its application in livestock production. The objectives of this study were to develop and characterize, in vitro and in vivo, a citral product encapsulated with a soy protein-soy polysaccharide Maillard reaction product (SPPMP) through spray drying technology. During initial formulation screenings, SPPMP significantly outperformed the physical mixture of soy protein and soy polysaccharide (SPP). A formulation comprising 10.4% SPPMP and 13% citral was selected for further evaluation. When tested in the simulated gastrointestinal system, the SPPMP-microparticles retained over 75% of citral after the gastric phase and released the citral completely during the intestinal phase. The release of citral from the SPPMP- and SPP-microparticles in the simulated gastrointestinal system followed the zero-order kinetics at the early phase (0–180 min), and a first order non-linear BoxLucasl kinetics at the later phase (>180 min). The release kinetic parameters were significantly better for SPPMP-microparticles compared to SPP-microparticles (p < 0.05). When tested in vivo, a threefold increase in citral concertation was detected in the intestinal digesta obtained from chickens fed with SPPMP-microparticles compared to chickens fed with non-encapsulated citral. Good long-term stability of citral in SPPMP-microparticles was observed. The current study demonstrates that SPPMP is a suitable encapsulation wall material for intestinal delivery of citral and potentially other similar hydrophobic compounds. [Display omitted] • Citral was encapsulated by soy protein-polysaccharide Maillard conjugate (SPPMP). • Maillard conjugation improved the resistance of soy protein to gastric digestion. • Spray-dried citral in SPPMP microparticles showed good stability during storage. • SPPMP encapsulation enhanced intestinal delivery of citral in experimental chickens. [ABSTRACT FROM AUTHOR]

This study investigated the complexes formed between ovalbumin (OVA) and gum arabic (GA) and their ability to stabilize oil-water emulsions. The stability of the emulsions stabilized by the OVA/GA complexes was evaluated by measuring storage time (1–7 days), salt concentration (0–100 mM NaCl), and heat (40–90 °C, 30 min) stability at pH 3.8–7.0. The results showed that the stability of the OVA-stabilized emulsion was greatly improved by an OVA/GA ratio of 1:2 and acidic pH. Above or below 1:2, the emulsion was unstable due to depletion or bridging flocculation. Emulsions saturated with OVA/GA complexes were stable with changing pH, storage time, and heat treatment (up to 90 °C). However, the OVA/GA complexes did not improve the stability of the emulsions when salt concentrations were varied. The experimental results demonstrated that OVA/GA complexes could be used to prepare stable emulsion structures, which may be useful in the beverage industry. [ABSTRACT FROM AUTHOR]

The emulsion stabilized by loose and branched particles was easy to flocculate and cream. And compact particles formed a stable interfacial membrane, which could resist hydrophobic interaction and flocculation. [Display omitted] • Relationship between particle characteristics and emulsion properties was analyzed. • Compactness and stability of particle depend on protein content in a certain range. • Compact particles could resist hydrophobic interaction and flocculation. • The important role of particle compactness in emulsion stability has been proved. A protein/polysaccharide colloidal particle was prepared via combined complex coacervation and heat-induction. When the ratio of ovalbumin (OVA) to carboxymethylcellulose (CMC) was at 1:2, loose flexible particles (low D f) with low surface hydrophobicity were obtained. Conversely, dense and compact particles (high D f) were easily formed at a higher OVA/CMC ratio. Only in the appropriate OVA/CMC ratio, pH will have a greater impact on the colloidal particles. At the pH value of 4.4, the OVA/CMC ratio had a greater impact on the colloidal particles compared to pH. The emulsion stabilized by loose particles had a mean particle size of 3888 nm and was easily flocculated and creamed. On the other hand, compact particles formed a stable emulsion, which had a higher exponent of Δ r2 (0.867) and could resist flocculation during the 7 days storage. As such, the results showed that stable emulsion could be realized by utilizing compact particles as emulsifiers. [ABSTRACT FROM AUTHOR]

To analyze the influence of different preparation methods on the interfacial adsorption behavior of biological macromolecular colloidal particles, three types of emulsions were prepared in this work. Furthermore, the stability mechanisms of the emulsions prepared via different preparation methods were also described. The result showed that the emulsions with relatively high viscosity or relatively severe aggregation displayed longer decay time. The viscoelastic data indicated that all emulsions formed a weakly viscous gel structure, while the MSD data shows that the movement of the droplets was unrestricted by the "cage" structure. The emulsions treated by ultrasonic emulsification possessed a smaller particle size and good stability as compared to those treated by high-speed shearing process and high-pressure homogenization. For the emulsions stabilized by biological macromolecular colloidal particles, a moderate energy input (ultrasonic emulsification) and a longer-acting duration were necessary. Thus, these results provided new concepts for the development and utilization of emulsions in the food industry. [Display omitted] • Diffuse Wave Spectroscopy is used to detect the microstructure of emulsion. • The relatively tight cage structure promotes the stability of emulsion. • High pressure homogenization leads to flocculation of colloidal particles emulsion. • The ultrasonic emulsification is the best method for colloidal particle emulsion. • Colloidal particles emulsion requires moderate energy input and longer acting time. [ABSTRACT FROM AUTHOR]

OVA (ovalbumin)/CMC (sodium carboxymethylcellulose) nanoparticles are prepared by combining complex coacervation and thermal induction. The effect of different parameters on stability of OVA/CMC nanoparticles (different ratios, pH, temperature, salt concentration and storage time) is investigated. And then the loading and stabilizing mechanism of particles on curcumin are further analyzed. After heating, OVA and CMC in particle could further cross-linking and a highly salt-tolerant and ultra-long stable nanoparticle can be formed. OVA/CMC nanoparticle with the loose structure of wool ball could effectively load curcumin with the loading content and loading efficiency of 36.40 and 95.40%, 36.30 and 92.82%, 36.0 and 94.48% for the ratios of 1:2, 1:1 and 2:1, respectively. Curcumin-loaded of OVA/CMC nanoparticles show good DPPH· scavenging activity, Ferric-reducing ability and ABTS+ scavenging activity compared with curcumin/water. The results can be useful for designing food and beverage particle with improving bioactive substances functional properties. • OVA/CMC nanoparticles were prepared by combining complex coacervation and thermal induction. • Nanoparticles showed ultra-long stability and high salt concentration tolerance. • OVA/CMC nanoparticles with concave/convex structure exhibited good curcumin load capacity. • Curcumin-loaded nanoparticles showed and improved antioxidant activity than free curcumin in water. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Active component delivery system was fabricated by anti-solvent precipitation. • A stable interfacial film is formed in GA-zein-curcumin due to an electrostatic effect. • GA-zein-curcumin system showed good stability under certain environment conditions. Abstract To evaluate the performance of biopolymer fabricated nanoparticle under commercial processing conditions, the stability of gum Arabic (GA)-zein-cur (curcumin) colloidal system was recorded and analyzed. The results showed that GA-zein-cur system is colloidal stable in the pH range of 5–8, however, encapsulated curcumin degraded rapidly as long as the pH changes. As for processing temperature, more than 70 °C will affect the spatial structure of zein and leading to the leak or exposure of encapsulated curcumin which result in the degradation of curcumin. Na+ has no significant effect on colloidal and chemical performance of nanoparticles while Fe3+ could penetrate the zein nanosphere and compromise curcumin. Results of our work imply that the protein-based core-shell delivery system has advantages in solubilizing the hydrophobic compounds and has certain ability to protect the encapsulated material against the unfavorable environment. [ABSTRACT FROM AUTHOR]

Egg white protein is a kind of protein resource with distinctive nutritional value and functional properties, while performing weak emulsifying stability under neutral and alkaline conditions, limiting application in food industry. This study, we investigated the effect of enzyme on characteristics of egg white protein (EWP) and synergistic efficiency of pectin addition on properties (thermal stability, salt resistance and antioxidant activity) of emulsions stabilized by original or hydrolyzed EWP. The EWP solutions were incubated at pH 7.0, under 50 °C for 2 h, with various amount of enzyme (0%, 0.5%, 1%, 2%, and 4%) added in. With enzyme concentration increased, more ovotransferrin and ovalbumin were hydrolyzed, and more hydrophobic amino acids exposed to polar environment, especially tyrosine. In addition, the DPPH and ABTS radical scavenging activity of EWP increased with enzyme concentration increased. Pectin addition can effectively improve the stabilization of the emulsion droplets, inducing smaller effective diameter and polydispersity index. In comparison, the emulsions stabilized by hydrolyzed EWP with 0.3% pectin behaved better thermal and salty stability, while with poorer antioxidant capacity attributed to weaker intermolecular interactions. The rheological measurement showed that the viscosity of hydrolyzed EWP stabilized emulsion was relatively lower and G′ was more dependent on frequency, indicating weaker cross-links among droplets. The results may provide theoretical guidance for application of enzymatic and polysaccharide blends in improving protein functionality. [ABSTRACT FROM AUTHOR]

The effect of pure gum (PG) on the properties of oil-in-water emulsions prepared with whey protein isolate (WPI) was studied at different pH (3–7). The mean particle diameters, turbidity, rheological properties and stability of the emulsions stabilized by the WPI/PG mixture were evaluated. The results showed that the emulsion prepared with WPI/PG had a small particle size and good stability, because the WPI/PG mixture created a relatively thick surface layer, reducing interactions between droplets through steric repulsion. All the emulsions exhibited shear-thinning behaviors at tested shear rates in the range 0.1–300 s −1 , the apparent viscosity of WPI/PG emulsions increased with increasing the PG concentration under different pH. A viscosity hysteresis phenomenon was observed in the process of heating up, which meant that the apparent viscosity was not a single-valued function of temperature. The emulsions prepared with WPI/PG (pH 3, 6% PG) were more resistant to environmental stress than those coated with WPI/arabic gum (AG). The experimental results have implications for the development of emulsion-based delivery systems for use in food and beverage products. [ABSTRACT FROM AUTHOR]