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The interaction of bubbles with phase interfaces is an important phenomenon in science and industry. In this paper, the variation in bubble behavior and the characteristics of surface liquid film formation and shedding at the oil–water interface are investigated using bubble visualization high-speed photography and numerical simulation. The results show that the bubble rise trajectories can be divided into three different sets when the bubbles rise in a system composed of two mutually incompatible liquids, and the bubble shapes are more stable in white oil compared to water. During the passage of the bubble across the oil–water interface, the water phase is entrained to form a liquid film covering the bubble. We found that the change in the bubble liquid film and the collapse process of the water column are closely related to the bubble size. The trends of Eotvos (Eo) numbers for bubbles of different diameters in the oil–water coexistence system are approximately the same, with the Eo numbers of larger bubbles being much larger than those corresponding to smaller bubbles, from the beginning to the end. After crossing the oil–water interface, the Eo number of larger-diameter bubbles keeps fluctuating over a long distance before finally stabilizing. The Eo number of small-diameter bubbles remains essentially stable after crossing the oil–water interface. [ABSTRACT FROM AUTHOR]

ABSTRACT Microbial-induced oil degradation (MIOD) has a wide range of applications, such as microbial enhanced oil recovery and bioremediation of oil pollution. However, our understanding of MIOD is still far from complete. Particularly, how is the dynamics of degradation process at the microscale level with a single-cell resolution remains to be disclosed. In this work, using hexadecane droplets in water as a model system, we have studied the dynamics of hexadecane degradation by different strains, including Pseudomonas aeruginosa PAO1, IMP68, O-2-2, and Dietzia sp. DQ12-45-1b, at the microscale. Based on visualization of MIOD, the dynamics of MIOD can be characterized by a three-stage process, including adhesion, adaptation, and degradation stages. Although different strains showed similar three-stage dynamics of MIOD, the effective degradation rate varied and followed an order of PAO1 > O-2-2 > IMP68 > DQ12-45-1b under aerobic conditions. Different oxygen conditions were also tested, and the dynamics of MIOD was slowed down under anaerobic conditions in comparison to under aerobic conditions. Further investigations at the degradation stage revealed that biofilms formed at the oil-water interface enhanced oil degradation, but a prerequisite for such enhanced degradation is proper stimulation of biofilm cells in the course of biofilm formation. The findings in this work provided a detailed picture on the dynamics of MIOD at the microscale and would be beneficial for better applications of MIOD.IMPORTANCEMicrobial-induced oil degradation is environmental friendly and economic and has become a promising technique in the fields of enhanced oil recovery and remediation of crude oil-polluted environments. For better applications of microbial-induced oil degradation, understanding the degradation dynamics particularly at the microscale is crucial. In this study, we investigated the degradation dynamics of hexadecane oil droplets incubated with different strains, including Pseudomonas aeruginosa PAO1, O-2-2, IMP68, and Dietzia sp. DQ12-45-1b at the microscale by employing microdroplet-based methods and bacterial tracking techniques. The findings in this study provided a detailed picture on the dynamics of microbial-induced oil degradation at the microscale, which will deepen our understandings on the biodegradation mechanisms of alkanes and shed insights for developing more effective biodegradation techniques.

AbstractTo investigate the effect of ionic strength and pH on the interfacial adsorption capacity and emulsion stability of soy hull polysaccharide (SHP), a series of SHP emulsions with 10% oil content was prepared with 0–0.30 mol/L Na+ at pH 3.0 and 5.0. The results of droplets size, zeta potential, dilatational rheological, and cryo-scanning electron microscopy analyses showed that the droplets of the emulsion at pH 3.0 were smaller and the system was more stable than at pH 5.0, and Na+ effectively shielded the negative charge on the SHP surface, leading to more SHP adsorption to the interface and increasing viscosity; whereas too much Na+ weakened the repulsive forces between droplets, making it easier for the droplets to merge with each other and causing emulsion destabilization. The best emulsification capacity of SHP was achieved at pH 3.0 with 0.10 mol/L Na+, in which 58.62 ± 0.49% SHP would adsorb to the interface, and kept high zeta potential of interface with −30.00 ± 0.27 mV. Meanwhile, the emulsion prepared under this condition had good storage stability and exhibited small droplet size of 2.425 ± 0.004 µm after 30 days. In conclusion, above indicators demonstrated that SHP-stabilized emulsions were influenced by pH and Na+, this provides theoretical and practical support for selecting the most suitable acid-base and ionic environment to prepare food emulsion by SHP, or other anionic polysaccharides. [ABSTRACT FROM AUTHOR]

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this research, we used molecular dynamics simulation to study the transformation of a mixture containing oil, water, and potassium perfluorooctanesulfonate (KPFOS) from a "disordered" state to an "aggregated" state. During the simulation, we observed that the PFOS− molecules spontaneously migrated to the interface between the oil and water phases. The hydrophilic sulfonate groups were oriented toward the water phase, while the lipophilic fluorocarbon chains were oriented toward the oil phase. By analyzing the number density and charge density distribution, we found that PFOS− and K+ ions predominantly accumulated at the oil–water interface, with some K+ ions dispersed within the solution. Moreover, PFOS− formed a stable monomolecular film at the interface, creating a distinct "transition region" with a specific thickness. The mean square displacement (MSD) results indicated that self-assembled micelles composed of PFOS−-facilitated efficient migration of oil molecules within the system, displaying robust migration abilities. Further analysis of the radial distribution function revealed a high probability of K+ ions being found near the oxygen atoms in PFOS− due to charge attraction. Separating K+ ions from PFOS− at the interface required overcoming very strong interaction forces, which limited their migration. Weak van der Waals interactions were observed between the fluorocarbon chains and toluene, while hydrogen bonding interactions occurred between the sulfonate groups and water molecules, as identified through independent gradient model based on Hirshfeld partition analysis. These findings shed light on the complex kinetic processes governing the behavior of oil–water-KPFOS mixtures, providing valuable insights for future studies in this field. [ABSTRACT FROM AUTHOR]

Effectively enhancing oil recovery can be achieved by reducing the viscosity of crude oil. Therefore, this paper investigated the viscosity reduction behavior of carbon nanotube viscosity reducers with different molecular structures at the oil–water interface, aiming to guide the synthesis of efficient viscosity reducers based on molecular structure. This study selected carbon nanotubes with different functional groups (NH2-CNT, OH-CNT, and COOH-CNT) for research, and carbon nanotubes with varying carbon chain lengths were synthesized. These were then combined with Tween 80 to form a nanofluid. Scanning electron microscopy analysis revealed an increased dispersibility of carbon nanotubes after introducing carbon chains. Contact angle experiments demonstrated that -COOH exhibited the best hydrophilic effect. The experiments of zeta potential, conductivity, viscosity reduction, and interfacial tension showed that, under the same carbon chain length, the conductivity and viscosity reduction rate sequence for different functional groups was -NH2 < -OH < -COOH. The dispersing and stabilizing ability and interfacial tension reduction sequence for different functional groups was -COOH < -OH < -NH2. With increasing carbon chain length, conductivity and interfacial tension decreased, and the viscosity reduction rate and the dispersing and stabilizing ability increased. Molecular dynamics simulations revealed that, under the same carbon chain length, the diffusion coefficient sequence for different functional groups was -NH2 < -OH < -COOH. The diffusion coefficient gradually decreased as the carbon chain length increased, resulting in better adsorption at the oil–water interface. This study holds significant importance in guiding viscosity reduction in heavy oil to enhance oil recovery. [ABSTRACT FROM AUTHOR]

[Display omitted] Two major protein families are present in rapeseed, namely cruciferins and napins. The structural differences between the two protein families indicate that they might behave differently when their mixture stabilises oil–water interfaces. Therefore, this work focuses on elucidating the role of both proteins in interface and emulsion stabilisation. Protein molecular properties were evaluated, using SEC, DSC, CD, and hydrophobicity analysis. The oil–water interface mechanical properties were studied using LAOS and LAOD. General stress decomposition (GSD) was used as a novel method to characterise the nonlinear response. Additionally, to evaluate the emulsifying properties of the rapeseed proteins, emulsions were prepared using pure napins or cruciferin and also their mixtures at 1:3, 1:1 and 3:1 (w:w) ratios. Cruciferins formed stiff viscoelastic solid-like interfacial layers (G s ′ = 0.046 mN/m; E d ′ = 30.1 mN/m), while napin formed weaker and more stretchable layers at the oil–water interface (G s ′ = 0.010 mN/m; E d ′ = 26.4 mN/m). As a result, cruciferin-formed oil droplets with much higher stability against coalescence (coalescence index, CI up to 10%) than napin-stabilised ones (CI up to 146%) during two months of storage. Both proteins have a different role in emulsions produced with napin-cruciferin mixtures, where cruciferin provides high coalescence stability, while napin induces flocculation. Our work showed the role of each rapeseed protein in liquid–liquid multiphase systems. [ABSTRACT FROM AUTHOR]

Gathering and transportation pipelines often appear shutdown condition due to damage, leakage, and other reasons. The reasonable maintenance time should be controlled by closely combined with the change law of the oil-water temperature in the pipeline. This paper established a multi-field coupling 3-D heat transfer mathematical model of the oil-water pipeline environment based on the two-phase shutdown pipeline as the research object. According to the changing law of the oilwater temperature field and flow field under a typical pipe diameter, the evolution behavior of the gelation layer in the pipe and the transformation process of heat transfer mode were analyzed, and the heat transfer characteristics between oilwater phase and its interface in the pipe were defined. With the liquid phase ratio of the oil phase changing the rule, reasonable maintenance time suggestions were given for gathering and transporting pipelines with different water content. [ABSTRACT FROM AUTHOR]

[Display omitted] Plant protein ingredients from similar sources can vary in functionality not only because of compositional differences, but also because of differences in their structure depending on their processing history. It is essential to understand these distinctions to develop novel food emulsion using plant proteins. It is hypothesized that differing interfacial properties can be attributed to their structures, aggregation, and colloidal states. The adsorption behavior of a commercial protein isolate, homogenized or non-homogenized, was compared to a mildly extracted isolate to evaluate the effect of aggregation state and structural differences. After characterization of the particle size and protein composition, the interfacial properties were compared. Atomic force microscopy provided evidence of interfaces packed with protein oligomers regardless of the treatment. Differences in adsorption kinetics and interfacial shear rheology depending on oil polarity suggested different interfacial structures. A polydisperse mixture of protein oligomers resulted in increased rearrangements and protein-protein interactions at the interface. Homogenization of commercial proteins resulted in a lower interfacial tension and less elastic interfaces compared to those of native proteins due to the presence of larger aggregates. This study highlights how the interfacial properties can be related to the protein aggregation state resulting from differences in processing history. [ABSTRACT FROM AUTHOR]

The waxy oil-water interface has become a topic issue in the field of a two-phase oil-water pipe flow. Although some progress has been achieved in the understanding of interfacial rheological properties of the water-in-oil emulsion (W/O), the effect of surfactants (the main constituents of petroleum crude oil) still remains unclear. To test whether the structure of hydrophobic chains of surfactants influences the waxy oil-water interface, we monitored interfacial rheological parameters under different nonionic surfactants (Span80/60/65) using a DWR interfacial shear rheometer. Among these surfactants, the oil-water interface of Span65 characterized by multi-hydrophobic chains had the largest interfacial viscosity and critical storage modulus. A weak strain overshoot interface of Span65 suggested that sorbitan tristearate molecules provided a dominant contribution to the interfacial rheological properties of the waxy oil-water interface with much fewer effects of the interaction between wax molecules and surfactants. However, Span60/80 with a single hydrophobic chain was coupled to wax molecules and reshaped the waxy oil-water interface structure, which replaced the original wax crystal position (the interfacial viscosity and critical storage modulus decrease) and yielded an interfacial structure (the critical strain increase). The wax-surfactant interactions of Span60/80 with different hydrophobic chain saturation were discussed. These interfacial properties are of practical importance for the technological operations in oil production. [ABSTRACT FROM AUTHOR]

The construction of organic–inorganic hybrid supramolecular polymers using polyoxometalate (POM) as building block is expected to bring new opportunities to the functionalization of supramolecular polymers and the development of novel POM‐based soft materials. Here, by using the orthogonal self‐assembly based on host–guest interactions and metal‐ligand interactions, we report the in situ construction of a novel POM‐based hybrid supramolecular polymer (POM‐SP) at the oil‐water interface, while the redox and competitive responsiveness can be triggered independently. Moreover, the binding energy of POM‐SP at the interface is sufficiently strong so that the assembly of POM‐SP jams, allowing the stabilization of liquids in nonequilibrium shapes, offering the possibility of fabricating all‐liquid constructs with reconfigurability. [ABSTRACT FROM AUTHOR]

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Ultrasound is widely used as a novel non‐thermal processing technique to improve protein properties. In recent decades, applying ultrasound‐assisted emulsification (UAE) to produce protein‐stabilized emulsion has attracted people's attention. Instead of applying ultrasound to treat a single protein solution, UAE treatment refers to the use of sonication to a mixture of protein and oil. The purpose of this study was to compare the different effects of ultrasound treatment on the properties of myofibrillar protein (MP) in the presence or absence of soybean oil. A suitable sonication power was selected based on the change in emulsion properties. RESULTS: 300 W sonication power was selected because of its most effectively decreased emulsion droplet size and increased absolute zeta potential. Sonication more significantly increased the protein carbonyl content and disulfide bonds of the MP–soybean oil sample compared with the MP sample. Due to the presence of oil, ultrasound could unfold more protein molecules, illustrated by a lower α‐helix content and intrinsic fluorescence intensity, and a higher surface hydrophobicity. Results of liquid chromatography–tandem mass spectrometry illustrated that sonication enhanced the myosin heavy chain and actin content at the soybean oil interface as well as accelerated the myosin light chain to separate from myosin in the MP–soybean oil system. CONCLUSION: Ultrasound treatment could lead to a higher level of protein oxidation and greater protein molecule exposure in the MP in the presence of oil system than in the oil‐free MP system. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This study investigated the effect of the combined use of sodium caseinate (CAS), commercial phosphatidylcholine (PC), and modified PCs on the physical and oxidative stability of 70% fish oil-in-water emulsions. Caffeic acid was covalently attached to both modified PCs (PCs originated from soy and eggs) in order to increase the antioxidant activity of PCs and investigate the advantage of bringing the antioxidant activity to the close proximity of the oil-water interface. Results showed that oxidative stability was improved when part of the PC was substituted with modified soy PC or egg PC. Emulsions containing a low concentration of modified PCs (10 wt.% of total PC) resulted in a prooxidative effect on the formation of hydroperoxides compared to emulsions with free caffeic acid. On the other hand, a decrease in the formation of volatile oxidation products was observed for emulsions containing higher levels of modified PCs (60 wt.% of total PC) compared to the emulsions with free caffeic acid added at its equivalent concentration. Increased concentrations of modified PCs provided better oxidative stability in high-fat emulsions, independent of the modified PC type. Moreover, when oxidation was initiated by producing singlet oxygen near a single oil droplet using a focused laser, fluorescence imaging showed that the oxidation did not propagate from one oil droplet to another oil droplet. [ABSTRACT FROM AUTHOR]

Whey proteins can form thin layers at the interface of non-miscible liquids like oil drops and water by emulsifying. The interfacial activity and the rheology of the interfacial films constitute a crucial aspect in assessing ingredients’ ability to form and stabilize emulsions. Although cow-origin whey protein concentrates (WPC) have been extensively used in the food industry, the WPC from buffalo (BWPC) still needs to be studied. In this context, the objective of this work was to explore the interfacial activity and the viscoelastic properties of BWPC at the oil-in-water (O/W) interfaces. WPC was used for comparison. With this purpose, BWPC and WPC were dispersed at 2.6x10-3 – 1.6% w/v in 10 mM phosphate buffer (pH 7) and equilibrat-ed at four °C for 24 h. Then, the equilibrium interfacial pressure (πeq) was registered through the Wilhelmy plate method. Additionally, adsorption dynamics at the O/W interface at protein concentrations of 0.5 and 1% were obtained over three h with a drop tensiometer. Subsequently, the rheological dilatational behavior (10% deformation amplitude and 0,1 Hz of angular frequency) was evaluated. Plate tensiometry showed that πeq of BWPC and WPC solutions increased from 9.9 to 16.7 mN/m and 11.5 to 15.0 mN/m, respectively, and conform protein concentration increased. An intersection between π – concentration isotherms was observed, indicating that below protein concentration of 1.3x10-2%, the πeq of WPC was higher than BWPC. This observation could be attributed to compositional differences and the possibility of generating different structural patterns in the interface. The drop tensiometer displayed that π increased with time for both protein concentrates, indicating the protein adsorption at the O/W interface. Interfacial rheology results indicated a gradual increase in the solid or elastic character (Ed) over time for both types of proteins, indicating more cohesive and packed structures. Ed of BWPC was higher than WPC at the lowest protein concentration, while the opposite also occurred. This behavior can be explained by considering that the higher the protein concentration, the stronger interactions among BPWC proteins occur. In conclusion, BWPC increased the interfacial pressure to a greater extent than WPC and concomitantly formed films with a higher solid character. These findings contribute to considering the use of BWPC as an efficient emulsifier agent with the benefits of adding value and minimizing the environmental impact of this byproduct.

Bile Salts (BS) adsorb onto emulsified oil droplets to promote lipolysis and then desorb, solubilizing lipolytic products, a process which plays a crucial role in lipid digestion. Hence, investigating the mechanism of adsorption and desorption of BS onto the oil–water interface is of major importance to understand and control BS functionality. This can have implications in the rational design of products with tailored digestibility. This study shows the adsorption and desorption curves of BS at air–water and oil–water interfaces obtained by pendant drop tensiometry. Three BS have been chosen with different conjugation and hydroxyl groups: Sodium Taurocholate (NaTC), Glycodeoxycholate (NaGDC) and Sodium Glycochenodeoxycholate (NaGCDC). Experimental results show important differences between the type of BS and the nature of the interface (air/oil–water). At the air–water interface, Glycine conjugates (NaGDC and NaGCDC) are more surface active than Taurine (NaTC), and they also display lower surface tension of saturated films. The position of hydroxyl groups in Glycine conjugates, possibly favors a more vertical orientation of BS at the surface and an improved lateral packing. These differences diminish at the oil–water interface owing to hydrophobic interactions of BS with the oil, preventing intermolecular associations. Desorption studies reveal the presence of irreversibly adsorbed layers at the oil–water interface in all cases, while at the air–water interface, the reversibility of adsorption depends strongly on the type of BS. Finally, dilatational rheology shows that the dilatational response of BS is again influenced by hydrophobic interactions of BS with the oil; thus, adsorbed films of different BS at the oil–water interface are very similar, while larger differences arise between BS adsorbed at the air–water interface. Results presented here highlight new features of the characteristics of adsorption layers of BS on the oil–water interface, which are more relevant to lipid digestion than characteristics of BS adsorbed at air–water interfaces. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the development of reserves, optimal technologies must be introduced to meet the regular increase in demand for hydrocarbons. Injection of low-salinity water is one of these technologies that have been shown to be effective in solving this problem. Accordingly, low-salt water is investigated as a potential method to increase terrigenous oil recovery. Based on modelling the flooding of solutions with different salinities, the effect of salt concentration on oil displacement efficiency during re-injection was assessed. Salinity reduction efficiency was examined by comparing oil recovery after flooding with high salinity water. Due to active interactions at the oil-water interface, including an increase in viscoelasticity, the oil recovery factor increased with a decrease in salinity. Oil recovery increased by 1.3 – 2% as water salinity decreased. [ABSTRACT FROM AUTHOR]

Nonionic emulsifiers (NE) are widely used in sponge cakes because they can effectively improve the foaming properties of whole egg liquids (WEL). The WEL are rich in protein, lipids and water, forming air-water and oil-water interface during whipping and foaming. However, different NE plays different roles in the interface. No systematic study has been conducted on the stabilization mechanism of WEL by NE. This study first investigated the effect of different NE on the foaming properties of WEL. It was found that WEL with sucrose ester-9 (SE-9) had the highest foam stability (FS) (92.52%), while that with Tween 80 had the lowest (75.55%). It was found that this was related to the higher interfacial protein substitution ability of Tween 80. Next, free triglyceride content and CLSM analysis confirmed that NE promoted the formation of more oil-water interfaces in the foam. Moreover, NE could improve FS by reducing droplet size and increasing viscosity. Finally, the higher surface activity of NE than proteins was demonstrated by interfacial adsorption kinetics and dilatation rheology. SE-9 interacted with proteins at the air-water interface to enhance interfacial rigidity, whereas adsorption of Tween 80 led to a decrease in the rearrangement rate. The results also showed that the formation of oil-water interfacial films was dominated by the adsorption of NE. This study illustrated how different NE stabilized air-water and oil-water interfaces, and the effect of synergistic/competitive interactions with proteins on the stability of the interfaces. This will provide new insights into the stability regulation of WEL foam. [Display omitted] • Tween 80 was not conducive to the stabilization of whole egg liquid (WEL) foam. • Nonionic emulsifiers (NE) promoted oil-water interface formation in WEL foam. • Tween 80 competed with proteins for adsorption at the air-water interface. • Sucrose ester-9 and proteins synergistically adsorb at the air-water interface. • Formation of the oil-water interfacial film was dominated by the adsorption of NE. [ABSTRACT FROM AUTHOR]

[Display omitted] • The interaction parameter between beads in the BGF/n-pentanol/dodecane/water system is established using the Blends method. • The self-assembly, interface, and microstructure of the microemulsion collector are studied by dissipative particle dynamics. • The polar groups of BGF are close to the water in the system, and the non-polar groups tend to be immersed in the dodecane. • N-pentanol molecules fill in the gaps between BGF in the dodecane-water interface. The formation process of microemulsion collectors for coal slime flotation and the underlying mechanisms governing their structure-related interfacial properties are challenging to observe visually by experiments. Dissipative particle dynamics (DPD) technology is employed to investigate the self-assembly process, interface formation, and microstructure of the microemulsion collector, which helps understand the microcosmic formation mechanism of microemulsion collectors and enriches the fundamental theory. The interaction parameter among the beads in the coarse-grained models of dodecane, water, n-pentanol, and BGF molecules was calculated utilizing the Blends method, and the DPD force field for the BGF/n-pentanol/dodecane/water (B-P-DW) system was established. The structure studies showed that the structural type of B-P-DW system transitions from water-in-oil (W/O) to bicontinuous (B.C.), and subsequently to oil-in-water (O/W) with the increase of water content. The self-assembly process of microemulsion collectors showed that the molecules within the B-P-DW system collided and aggregated with increasing simulation time. Specifically, water (or dodecane) molecules formed a rounded or rod-like structure dispersed phase, and dodecane (or water) molecules aggregated to form the continuous phase. Microstructure analyses revealed that BGF molecules exhibit preferential orientation upon adsorption at the oil–water interface within B-P-DW system. Specifically, the polar groups positioned proximal to the water, while the non-polar groups were predominantly immersed in the dodecane. Additionally, the interstitial spaces between BGF molecules were occupied by n-pentanol molecules. [ABSTRACT FROM AUTHOR]

Demulsification of stable W/O emulsions poses a challenge in crude oil processing. The terahertz pulse electric field is introduced to disrupt the hydrogen bond network between water molecules, enhancing water mobility in the oil phase and facilitating the rupture of the interface membrane for efficient oil-water separation. This presents a potential opportunity for economically streamlining of crude oil emulsions processing. [Display omitted] • The introduction of a THz pulse electric field disrupts the hydrogen bond network among water molecules. • The penetration ability of water molecules into the interfacial region between the two phases is heightened. • The THz pulse electric field reduces oil-water interface tension, facilitating efficient coalescence of water droplets. • Altered interface structure is evidenced by the weakening of the electric double-layer structure at the oil-water interface. Demulsifying highly stable W/O emulsions, composed of heavy oil and water, is crucial for simplifying crude oil processing, reducing production costs, and mitigating environmental pollution. In these emulsions, aromatic components in the oil phase stack via π-π interactions, while hydrogen bonds stabilize the water phase. This leads to the creation of a strong oil-water interface through electrostatic attraction, ultimately hindering water droplet coalescence and oil-water separation. In this study, a 1.0 THz pulse electric field is introduced to effectively disrupt the hydrogen bond network among water molecules by inducing hydrogen bond resonance. This disruption contributes to increased water mobility in the oil phase, weakened stability of the oil-water interface film, and facilitates efficient water droplet coalescence in the oil phase. The results show that throughout the demulsification process, the average number of hydrogen bonds per water molecule rapidly decreases from 1.41 to 1.08 within 100 ps. The upper and lower limits of hydrogen bond lifetimes decrease by 8.12 ps and 3.24 ps, respectively. This indicates a significant disruption in the stability of hydrogen bonds between water molecules. Concurrently, the terahertz pulse electric field disrupts the initially stable oil-water interface film of the emulsion system, leading to a noteworthy reduction in the oil-water interface tension from 54.3 to 39.2 mN·m−1. The self-diffusion coefficient of water molecules increases from 1.33 to 2.62 Å2·ps−1, signifying that water molecules are more inclined to penetrate the interfacial region between the two phases. Additionally, the terahertz pulse electric field induces alterations in the arrangement of water molecules, resulting in the rearrangement of electrons in the water phase and disrupting the originally stable electrical double layer structure of the oil-water interface. This study provides novel insights into the development of efficient and environmentally friendly electric demulsification technologies, holding significant potential for widespread industrial applications. [ABSTRACT FROM AUTHOR]

Biosurfactants are surface-active molecules obtained from natural sources and potential substitutes for various applications where their petrochemical counterparts dominate. Different efforts have been made to produce tailored and efficient biosurfactants, including rational design. However, there is limited information about the rational design of peptide-based biosurfactants and their interfacial behavior at the molecular level. In this work, the interfacial activity of two novel rationally designed peptides (Surf-UAC1 and Surf-UAC2) was evaluated by means of molecular dynamics (MD) simulations. Both peptides were in silico designed based on the properties of the amino acids. Their stabilities, conformations, mass density profiles, orientation, interaction energies, and average interfacial tension were assessed at the decane-water interface. Results were compared to those obtained with the widely used surfactant Tween 20®, simulated under the same conditions. Here, a new methodology based on a sequence of MD simulations is proposed. Results show that this methodology provides accurate interfacial tension data for the decane-water interface. The peptides are randomly adsorbed at low concentrations, but as the concentration increases, the interface becomes saturated, and an irregularly shaped peptide cluster is formed. This behavior strongly suggests that an adsorption barrier prevents the peptides from reaching the interface after interfacial saturation. Reorganization at the interface was evidenced. [Display omitted] • Peptides with surface activity were rationally designed in silico. • Biosurfactants were probed at liquid-liquid interfaces via Molecular Dynamics. • A novel methodology for the dynamic interfacial tension was developed and tested. • Hydrophilic/hydrophobic motifs are responsible for sorption and reorganization. [ABSTRACT FROM AUTHOR]

[Display omitted] Almost all Langmuir-Blodgett (LB) films were prepared with the classical Langmuir film balance, developed more than a century ago. To date, the success of the classical Langmuir film balance and the LB transfer technique is primarily restricted to the study of self-assembled monolayers at the air-water surface. It is challenging to study self-assembled monolayers at the oil-water interface, since the Langmuir film balance requires stacked oil and water layers. We hypothesize that a newly developed experimental method, called constrained drop surfactometry (CDS), is capable of preparing and characterizing LB films from the oil-water interface. We have developed a novel droplet-based LB transfer technique capable of preparing LB films from the oil-water interface. In conjunction with atomic force microscopy, we have demonstrated the capacity of the CDS in studying a natural pulmonary surfactant film self-assembled at the perfluorocarbon-water interface, and have compared to the LB films prepared from the air-water surface using the classical Langmuir film balance. Our findings have demonstrated a novel paradigm for studying self-assembled monolayers and for preparing LB films from the oil-water interface. The CDS holds great promise for expanding the applicability of the traditional LB transfer technique from the air-water surface to the oil-water interface. [ABSTRACT FROM AUTHOR]

Compared with the traditional transportation of high-viscosity crude oil, water annular transportation has the advantages of low energy consumption and no change in crude oil composition. With the continuous development of marine heavy oil transportation, submarine oil pipelines are inevitably subjected to vibration and impact, affecting the annular flow in the pipeline. In this paper, the VOF model in Fluent software is used to simulate the stability of oil-water annular flow in a horizontal pipeline under different amplitudes and the interface characteristic parameters of annular flow. In addition, the influence of vibration on oil-water annular flow in the horizontal pipeline under different marine environments is studied. The results showed that the vibration parameters have an influence on the flow of oil-water annular flow in the horizontal pipeline. Under the condition of constant inlet velocity, the eccentricity degree of oil core is analyzed to reveal the law that the stability of annular flow decreases with the increase of amplitude. The relationship between the eccentricity of oil core and the vibrational parameters of pipes are explored in this paper. At the same time, the unit pressure drop under the condition of pipe vibration and its mechanism are studied. These results could provide references for parameters optimization of heavy oil-water annular flow transportation under vibration conditions. [Display omitted] • Oil-water annular flow under the impact of marine swell is numerically simulated. • Annular flow stability is described by pressure drop and flow characteristics. • Different vibration properties affect the stability of the oil-water annular flow. [ABSTRACT FROM AUTHOR]

Bacteria forming biofilms at oil-water interfaces have diverse metabolism, they use hydrocarbons as a carbon and energy source. Kombucha is a fermented drink obtained from a complex symbiotic culture of bacteria and yeast, where acetic acid bacteria present in kombucha use sugars as a carbon source to produce cellulosic biofilms. We hypothesize that Komagataeibacteraceae in kombucha can adsorb to and use hydrocarbons as the sole energy source to produce cellulosic biofilms. Hence we characterized a kombucha culture, studied bacterial adsorption and cellulosic biofilm formation of kombucha at the n-decane or mineral oil-kombucha suspension interface. The cellulosic biofilms were imaged using fluorescence microscopy and cryo-scanning electron microscopy, and their time-dependent rheology was measured.Komagataeibacter, the dominant bacterial genus in the kombucha culture, produced cellulosic biofilms with reduced cellulose biomass yield at the oil-kombucha suspension interfaces compared to at the air-kombucha suspension interface. The presence of biosurfactants in the supernatant secreted by the kombucha microbes led to a larger and faster decrease in the interfacial tension on both oil types, leading to the formation of stable and elastic biofilm membranes. The difference in interfacial tension reduction was insignificant already after 2 h of biofilm formation at the mineral oil-kombucha suspension interface compared to kombucha microbes resuspended without biosurfactants but persisted for longer than 24 h in contact with n-decane. We also demonstrate that Komagataeibacter in kombucha can produce elastic cellulosic biofilms using hydrocarbons from the oil interface as the sole source of carbon and energy. Thus Komagataeibacter and kombucha shows the potential of this system for producing valued bacterial cellulose through remediation of hydrocarbon waste.

This study investigated the effect of the combined use of sodium caseinate (CAS), commercial phosphatidylcholine (PC), and modified PCs on the physical and oxidative stability of 70% fish oil-in-water emulsions. Caffeic acid was covalently attached to both modified PCs (PCs originated from soy and eggs) in order to increase the antioxidant activity of PCs and investigate the advantage of bringing the antioxidant activity to the close proximity of the oil-water interface. Results showed that oxidative stability was improved when part of the PC was substituted with modified soy PC or egg PC. Emulsions containing a low concentration of modified PCs (10 wt.% of total PC) resulted in a prooxidative effect on the formation of hydroperoxides compared to emulsions with free caffeic acid. On the other hand, a decrease in the formation of volatile oxidation products was observed for emulsions containing higher levels of modified PCs (60 wt.% of total PC) compared to the emulsions with free caffeic acid added at its equivalent concentration. Increased concentrations of modified PCs provided better oxidative stability in high-fat emulsions, independent of the modified PC type. Moreover, when oxidation was initiated by producing singlet oxygen near a single oil droplet using a focused laser, fluorescence imaging showed that the oxidation did not propagate from one oil droplet to another oil droplet.

Rubisco is the most abundant protein on earth and has gained extensive attentions as a novel food ingredient, such as an emulsifier. Extraction methods can significantly affect its molecular structures and consequently influence its oil-water interface and emulsion stabilization properties. This work aims to elucidate the role of the Rubisco molecular structure in stabilizing the oil-water interface and the multiphase system of emulsions. Ultrafiltration (mild) and acid precipitation-alkaline redispersion (extensive) were used to extract Rubisco from spinach leaves. Protein molecular properties were characterized by size exclusion chromatography (SEC), circular dichroism (CD), and fluorescence spectrometry. Subsequently, the oil-water interfacial properties, including the adsorption and rheological behavior in both small and large dilatational and shear deformations, and the emulsion stabilization properties of Rubisco were investigated. We found that acid precipitation-alkaline redispersion produced a Rubisco extract (RA) with extensive structural reassembling, compared to the one produced by ultrafiltration (RU), for which nativity was mostly retained. RA had two-fold higher surface hydrophobicity than RU, and this caused RA to adsorb faster to the oil-water interface and developed a stiffer solid-like interface (G i ' = 26 ± 3 mN/m) than RU (G i ' = 15 ± 2 mN/m), which was also more resistant to density changes in large dilatational deformations. Consequently, RA displayed higher emulsifying activity and emulsion stability to coalescence during bulk shear and storage. Additionally, structural reassembly resulted in a higher value of the zeta potential of RA, which made the emulsion more stable against flocculation, compared to RU. Our study demonstrates that structural reassembly might be a useful strategy to improve the behavior of plant proteins in oil-water interface and emulsion stabilization, and may stimulate the development of new plant protein-stabilized emulsion-based products. [Display omitted] • The pH shifting extraction reassembled the structure of Rubisco (RA). • RA had higher surface hydrophobicity and charge than mildly extracted one (RU). • RA adsorbed faster to O/W interface than RU and stabilized smaller oil droplets. • RA-stabilized O/W interface was stiffer and more resistive to large deformation. • RA-stabilized emulsions were more stable to coalescence in bulk shear and storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two carbon quantum dots featured distinct affinities for the oil phase and water phase were synthesized. • The effect of nanoparticle movement on oil–water interface and bulk properties were investigated. • The oil mobilization performance of two carbon dots were clarified from pore scale and core scale. Active colloid particles have been used in many fields due to their good performance in enhancing mass transport or modifying interfacial energy. Previous studies have shown that both nanoparticles adsorbed at oil–water interface and those dispersed in bulk fluid could enhance oil recovery during the oil production process. It is challenge to directly compare these results and clarify the effect of nanoparticle's location on oil detachment from rock surface because different kinds of nanofluids were used in those work. Herein, the oil mobilization performance by nanoparticles adsorbed at oil–water interface and dispersed in the bulk phase were investigated from the pore-scale to core-scale by using one material. Two fluorescent quantum nanodots with different affinities for oil and water phases were synthesized using the same materials but with different compositions and solvents. Their locations were observed under the laser confocal microscopy. The nanoparticles adsorbed at the oil–water interface not only presented a lower interface tension, but also demonstrated a notable capability to change the wettability from oil-wet to water-wet due to its strong tendency to rock surface. The particles-laden interface can also increase the stability and shear viscosity of formed emulsions. Furthermore, it featured a larger swept area of 6.6 % in microfluidic flooding and a higher displacement efficiency of 1.7 % in the core flooding experiments. All these findings indicate that the particle-adsorbed at the oil–water interface is more favorable for enhanced oil recovery. [ABSTRACT FROM AUTHOR]

Lentil protein isolate (LPI) was investigated for its potential as a plant protein-based emulsifier. LPI consists mainly of globulins with high molecular weights which are relatively slow to adsorb and stabilize oil-water interfaces. Smaller proteins, such as whey protein, can stabilize the interface much faster, quickly forming a viscoelastic film that slows down the rate of droplet recoalescence, leading to smaller droplets. To increase the rate of adsorption, LPI was enzymatically hydrolyzed by pepsin at 1.5% and 4.5% degree of hydrolysis (DH), to obtain small peptides. The behavior of these peptides was studied at the oil-water interface in comparison to whey protein isolate (WPI) and native lentil protein isolate (LPI). Interfacial properties were investigated using dilatational and interfacial shear rheology in the linear viscoelastic regime (LVE) and nonlinear viscoelastic regime (NLVE) and these were related to protein characteristics and emulsion formation. The 1.5% and 4.5%DH LPI showed high surface hydrophobicity, and consisted mainly of low molecular weight peptides, which contributed to faster adsorption kinetics and consequently covered the interface faster than LPI. In dilatation, the native and hydrolyzed LPI-stabilized interfaces had comparable stiffness and were clearly weaker than WPI-stabilized interfaces, which contrasts with the results in shear deformations, where the former both had higher stiffness than WPI. Both hydrolyzed LPI and WPI formed more brittle and less stretchable interfaces compared to native LPI in both dilatational and shear rheology. In emulsification tests, native LPI produces the largest droplets, and the 4.5% DH LPI and WPI have the smallest droplet size. But, bridging flocculation was observed when emulsions were prepared with both hydrolyzed LPI, which may be attributed to inter-droplet hydrophobic interactions between small polypeptides. This can be linked to an increase in the surface hydrophobicity of hydrolyzed LPI. Thus, the use of native LPI as a stabilizer in emulsion preparation is preferable over the hydrolyzed samples, despite its larger droplet size. [Display omitted] • Hydrolyzed lentil protein isolates (LPI) exhibit high surface hydrophobicity. • LPI formed soft 2d glassy interfaces, whey protein isolate (WPI) formed 2d gel interfaces. • Hydrolyzed LPI formed interfaces similarly dense to WPI. • Hydrolyzed LPI produced smaller emulsion droplets than native LPI. • Bridging flocculation occurred in emulsions stabilized by hydrolyzed LPI. [ABSTRACT FROM AUTHOR]

This study investigated the effect of different magnetic field treatments (0, 3, 6, 9, 12 mT) on the structure and emulsification properties of myofibrillar protein (MP). The results showed that the emulsion stabilized by MP with 3, 6, 9 mT magnetic field treatments possessed higher emulsifying ability, storage stability and apparent viscosity, since magnetic field induced the structural unfolding of MP and exposed the hydrophobic groups (the surface hydrophobic increased from 30.10 to 43.73 μg). Meanwhile, the magnetic field treatments decreased the MP particle size from 1752.00 to 1278.67 nm, which was favorable for the diffusion and adsorption of proteins at the oil-water interface, thus improving the MP emulsification ability and stability. Furthermore, the 9 mT magnetic field-treated MP had the best ability to emulsify oil droplets with a more uniform and smaller emulsion size from 28.593 to 23.443 μm. However, high-intensity magnetic field treatment (12 mT) caused MP particles to aggregate and the hydrophobic binding sites to be buried, which was not conducive to encapsulating oil droplets. • The mechanism of magnetic field improving the emulsification properties of MP was investigated. • Magnetic field reduced particle size and decreased the turbidity of MP. • Magnetic field unfolded MP structure and increased the surface hydrophobicity. • Magnetic field (9 mT, 3 h) treated MP contributed to form smaller and more uniform emulsion droplets. [ABSTRACT FROM AUTHOR]

The functional properties of protein are affected by their aggregation behavior and morphology. In this study, the self-assembled coconut protein aggregates with specific morphology, including small amorphous aggregates (WLA), spherical-like aggregates (SLA) and rod-like aggregates (RLA), were regulated to form. The self-assembled process resulted in a decrease in fluorescence intensity and an increase in the surface hydrophobicity of coconut protein. Fucoidan was added to improve the stability of protein solutions, and the interfacial adsorption behavior was evaluated by dilatational rheology analysis. The results showed that the aggregation state of coconut protein affected its ability to reduce surface tension, and the interfacial layers mainly exhibited elastic property at oil-water interface (tanφ < 0.5). For macroscale analysis, the emulsions based on self-assembled coconut protein exhibited smaller droplet size, better rheological properties and centrifugal stability, especially WLA and RLA. This study may provide a reference to inspire the utilization of self-assembled coconut protein in the food industry. [Display omitted] • Self-assembled coconut protein aggregates with specific morphology were fabricated. • Heat induction promoted the exposure of hydrophobic groups of coconut protein. • WLA/f, SLA/f and RLA/f exhibited better anti-perturbation ability at low amplitude. • WLA/f and RLA/f showed better emulsifying ability than CPI/f. [ABSTRACT FROM AUTHOR]

The contribution of glycyrrhizin (Gy) on the interfacial dynamic adsorption behaviour of the adsorbed layer formed by the bovine alpha-Lactalbumin (α-La) at the oil-water interface were investigated using the interfacial viscoelasticity and quartz crystal microbalance with dissipation (QCM-D) techniques. Compared to the individual α-La, Gy could decrease the interfacial tension, effectively enhancing their adsorption processing. The adsorption kinetic results revealed the diffusion rate of the α-La reduced at 0.5–2.0 mM Gy and its rate constant of rearrangement increased except for 2.0 mM. Also, Gy reduced the viscoelastic modulus including the elastic and viscous modulus of the adsorbed film formed by the α-La. Additionally, more adsorbed mass on the oil-water interface was observed in the α-La/Gy complex according to the QCM-D results, which can improve the stability at the oil-water interface. These results are expected to provide basic interfacial adsorption information for the film formed by multi-component. [Display omitted] • Interfacial dynamic adsorption behaviour of the α-La and glycyrrhizin (Gy) was studied. • α-La/Gy complex shows better surface activity than that of the α-La. • α-La/Gy complex improves the adsorption mass at the oil-water interface. [ABSTRACT FROM AUTHOR]

A novel oil–water interface method was successfully used to prepare rod-shaped silver selenide (Ag2Se) micro-nanoparticles from relatively low-toxic and cheap sodium selenosulfate by aging at 160 °C for 12 h. Then, under the same reaction conditions, AgCl/Ag2Se and Ag/Ag2Se micro-nanocomposites were synthesized by simply introducing different additives. The as-prepared micro-nanocomposites were characterized by the uses of XPS, XRD, SEM, BET, UV–vis, and PL. Cl− plays a bifunctional role to act as the adsorbate and the source of AgCl. Under the irradiation of a fluorescent light (36 W), the photocatalytic activity of Ag2Se-based micro-nanocomposites was evaluated by degradation of acid fuchsin (AF) and malachite green (MG) dyes in the presence of 0.6 wt.% H2O2. The results showed that the recombination of AgCl and the deposition of Ag exerted a significant influence on the light absorption of the particles. AgCl/Ag2Se and Ag/Ag2Se composites exhibited much higher catalytic activity than pure Ag2Se with the same surface area, Ag/Ag2Se composite particles have the best photodegradation performance, and the AF degradation rate is faster than MG. In aqueous solutions, positively charged Ag2Se micro-nano particles can be easily combined with AF anionic dyes instead of MG cationic dyes, resulting in more efficient AF photodecomposition. The significant increase in photocatalytic activity of AgCl/Ag2Se is mainly due to the heterojunction formed between AgCl and Ag2Se components, reducing the recombination of electron and hole pairs. In the case of Ag/Ag2Se composite material, the noble metal Ag acts as an electron trap to improve the separation of charges. In total, the high efficiency of the composite photocatalysts implies that it is of great significance in the degradation of environmental pollutants. [ABSTRACT FROM AUTHOR]

The three-phase separator is one of the most important pieces of equipment in the combined station of the oilfield. The control level of the oil–water interface directly affects the energy consumption of the subsequent production of the combined station and the effect of oil, gas and water separation. In order to avoid these situations, the Siemens PLC control system, configuration software WinCC and MATLAB were used. The OPC technology is used to connect communication between WinCC and MATLAB, and the genetic algorithm in MATLAB is used to obtain the optimal separation height of the oil–water interface under the produced liquid in different periods. Subsequently, through the Siemens PLC system and WinCC configuration software, the automatic control of the three-phase separator is achieved, and finally the water content of crude oil is significantly reduced. The system provides a visual interface function. In the future, it will also provide an effective simulation platform for the theoretical research and design of an automatic control system of an oilfield combined station. [ABSTRACT FROM AUTHOR]

[Display omitted] Janus particles (JPs) and surfactants express different behaviors at the oil–water interface under compression. When both are present at the interface, their synergies result in a different collapse mechanism than when present individually depending on the concentration of the JPs and surfactants. Coarse-grained modeling methods were used to probe the synergies between Janus nanoparticles and nonionic surfactants on the stability of an oil–water interface under compression. When both JPs and surfactants were present, the interface was covered at 0–55% area by JPs and contained surfactants at 0–40% of the interfacial surfactant concentration corresponding to the critical micelle concentration (CMC). Compression of the interface with only surfactants resulted in the expulsion of surfactant molecules to the water phase once the interfacial concentration of surfactant molecules reached the CMC value. Compression of a Janus particle-laden interface past the closed-packing point led to a buckled interface, so that the total interfacial area remained constant upon further compression. When both surfactants and JPs were present on the interface, JPs still caused buckling, which helped retain the surfactant molecules on the interface. The interface exhibited a higher level of deformation in presence of surfactants. When the surfactant concentration was high, under compression, the surfactants partitioned into the water phase, but the buckling of the interface persisted. [ABSTRACT FROM AUTHOR]

Bile Salts (BS) adsorb onto emulsified oil droplets to promote lipolysis and then desorb, solubilizing lipolytic products, a process which plays a crucial role in lipid digestion. Hence, investigating the mechanism of adsorption and desorption of BS onto the oil–water interface is of major importance to understand and control BS functionality. This can have implications in the rational design of products with tailored digestibility. This study shows the adsorption and desorption curves of BS at air–water and oil–water interfaces obtained by pendant drop tensiometry. Three BS have been chosen with different conjugation and hydroxyl groups: Sodium Taurocholate (NaTC), Glycodeoxycholate (NaGDC) and Sodium Glycochenodeoxycholate (NaGCDC). Experimental results show important differences between the type of BS and the nature of the interface (air/oil–water). At the air–water interface, Glycine conjugates (NaGDC and NaGCDC) are more surface active than Taurine (NaTC), and they also display lower surface tension of saturated films. The position of hydroxyl groups in Glycine conjugates, possibly favors a more vertical orientation of BS at the surface and an improved lateral packing. These differences diminish at the oil–water interface owing to hydrophobic interactions of BS with the oil, preventing intermolecular associations. Desorption studies reveal the presence of irreversibly adsorbed layers at the oil–water interface in all cases, while at the air–water interface, the reversibility of adsorption depends strongly on the type of BS. Finally, dilatational rheology shows that the dilatational response of BS is again influenced by hydrophobic interactions of BS with the oil; thus, adsorbed films of different BS at the oil–water interface are very similar, while larger differences arise between BS adsorbed at the air–water interface. Results presented here highlight new features of the characteristics of adsorption layers of BS on the oil–water interface, which are more relevant to lipid digestion than characteristics of BS adsorbed at air–water interfaces.

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Herein, we investigated the influence of emulsion process and DNA sequence on the morphology and surface property of the as-fabricated gel particles with and without payload. Nanogels can be prepared by using synthetic and kiwifruit-derived DNA above a certain concentration whilst nanocapsules can only be prepared by using a synthetic 19-mer DNA containing A nitrogen base. Kiwifruit-derived DNA was used to encapsulate two payloads, which were DOX and lipase, via oil-in-water and water-in-oil processes. The oil–water interface and payload-DNA interactions dictated their size, surface property, and payload encapsulation. The DOX-encapsulated nanogels exhibited comparable payload encapsulation regardless the emulsion process because DOX would not only intercalate in the DNA but also bind with the negatively charged DNA. The lipase-encapsulated nanogels prepared via oil-in-water process exhibited higher payload encapsulation and activity than those via water-in-oil process due to its hydrophobic nature and the creation of oil–water interface. Moreover, the advantage of enzyme encapsulation was revealed in the case at acidic solution pH. This study revealed the importance of the oil–water interface and payload-DNA interactions on the preparation of payload-encapsulated DNA nanogels. [ABSTRACT FROM AUTHOR]

Charge transfer (CT) interactions have been widely used to construct supramolecular systems, such as functional nanostructures and gels. However, to date, there is no report on the generation of CT complexes at the liquid–liquid interface. Here, by using an electron‐deficient acceptor dissolved in water and an electron‐rich donor dissolved in oil, we present the in situ formation and assembly of CT complex surfactants (CTCSs) at the oil–water interface. With time, CTCSs can assemble into higher‐order nanofilms with exceptional mechanical properties, allowing the stabilization of liquids and offering the possibility to structure liquids into nonequilibrium shapes. Moreover, due to the redox‐responsiveness of the electron‐deficient acceptor, the association and dissociation of CTCSs can be reversibly manipulated in a redox process, leading to the switchable assembly and disassembly of the resultant constructs. [ABSTRACT FROM AUTHOR]

There has been a growing interest in developing effective strategies to inhibit lipid oxidation in emulsified food products by utilization of natural phenolic antioxidants owing to their growing popularity over the past decades. However, due to the complexity of emulsified systems, the inhibition mechanism of phenolic antioxidants against lipid oxidation is rather complicated and not yet fully understood. In order to highlight the importance of polarity of phenolic antioxidants in emulsified systems according to the polar paradox, this review covers the recent progress on chemical, enzymatic, and chemoenzymatic lipophilization techniques used to modify the polarity of antioxidants. The partitioning behavior of phenolic antioxidants at the oil–water interface, which can be influenced by the presence of synthetic surfactants and/or antioxidant emulsifiers (e.g., polysaccharides, proteins, and phospholipids), is discussed. In addition, the emerging phenolic antioxidants among phenolic acids, flavonoids, tocopherols, and stilbenes applied in food emulsions are elaborated. As well, the interactions of polar–nonpolar antioxidants are stressed as a promising strategy to induce synergistic interactions at oil–water interface for improved oxidative stability of emulsions. [ABSTRACT FROM AUTHOR]