Emulsion Stability Research Articles

Application of AprX from Pseudomonas paralactis for the improvement of the emulsifying properties of milk, plant and insect protein and estimation of their hydrolysate’s bitter potential

AbstractProtein properties can be modified by selective enzymatic hydrolysis. In this study, the alkaline metalloendopeptidase AprX (Serralysin; EC 3.4.24.40) from Pseudomonas paralactis was used for the tailored hydrolysis of different food proteins resulting in the production of protein hydrolysates with improved emulsifying properties. Sodium caseinate, wheat gluten and buffalo worm protein were used for AprX hydrolysis at 40 °C and pH 8 to cover a spectrum of different protein sources. A maximum degree of hydrolysis (DH) of 13.1 ± 0.2%, 14.2 ± 0.1% and 20.7 ± 0.1% was reached for sodium caseinate, wheat gluten and the worm protein, respectively. The corresponding hydrolysate properties were analyzed regarding their particle size, peptide composition, solubility, viscosity, surface hydrophobicity and interfacial tension. The emulsifying properties were investigated by the oil-droplet size, ζ-potential and stability of emulsions prepared from the hydrolysates. Using partially hydrolyzed sodium caseinate (DH = 10.6%) as an emulsifier lead to an eightfold increase of the emulsion stability (t1/2 = 180 ± 0 min) compared to unhydrolyzed sodium caseinate. The emulsion stability using wheat gluten hydrolysates (DH = 11.9%) was increased 30-fold (t1/2 = 45 ± 5 min). Simultaneously, the solubility of gluten was increased by 60%. Buffalo worm hydrolysates (DH = 14.6%) had a twofold (t1/2 = 85 ± 5 min) increased emulsion stability. In conclusion, AprX can be used to improve the solubility and emulsifying properties of food proteins at a relatively high DH.

Effects of salt concentration, temperature, and blanching time on insect protein extraction yield: optimisation by response surface methodology

Abstract This study aimed to optimise the protein extraction yield from black soldier fly larvae by employing a blanching process to enhance protein solubility and mitigate oxidation. Through response surface methodology, we determined the optimal blanching conditions, with the temperature set at 85.152 °C, a duration of 12.411 s, and a sodium chloride concentration of 0.46 M. These parameters were selected to maximise protein solubility while minimising oxidation. The results of this study reveal significant improvements in protein functionality after blanching, particularly with respect to increased emulsification stability. Notably, no significant effect on foam formation was observed. These findings underscore the efficacy of blanching as a pre-processing step to enhance the quality of proteins extracted from black soldier fly larvae. Moreover, these optimised conditions have promising applications in various food and feed formulations, contributing to sustainable protein sourcing and processing methods. By addressing key challenges related to food security and environmental sustainability, this study provides valuable insights into the utilisation of insect proteins as an alternative protein source in the face of global challenges, such as climate change and dwindling natural resources.

Arginine-Loaded Nano-Calcium-Phosphate-Stabilized Lipiodol Pickering Emulsions Potentiates Transarterial Embolization-Immunotherapy.

Transarterial chemoembolization (TACE) continues to stand as a primary option for treating unresectable hepatocellular carcinoma (HCC). However, the increased tumor hypoxia and acidification will lead to the immunosuppressive tumor microenvironment (TME) featuring exhausted T cells, limiting the effectiveness of subsequent therapies following TACE. Herein, a stable water-in-oil lipiodol Pickering emulsion by employing calcium phosphate nanoparticles (CaP NPs) as stabilizers is developed and used to encapsulate L-arginine (L-Arg), which is known for its ability to modulate T-cell metabolism. The obtained L-Arg-loaded CaP-stabilized lipiodol Pickering emulsion (L-Arg@CaPL) with great emulsion stability can not only neutralize the tumor acidity via reaction of CaP NPs with protons but also enable the release of L-Arg, thereby synergistically promoting the reinvigoration of exhausted CD8+ T cells and effectively reversing tumor immunosuppression. As a result, TACE therapy with L-Arg@CaPL shows greatly improved therapeutic responses as demonstrated in an orthotopic liver tumor model in rats. This study highlights an effective yet simple nanoparticle-stabilized Pickering emulsion strategy to promote TACE therapy via modulation of the immunosuppressive TME, presenting great potential for clinical translation.

Effect of high hydrostatic pressure on the physicochemical characteristics of low sodium mortadella containing a high level of mechanically deboned poultry chicken meat.

High hydrostatic pressure (HHP) is an emerging technology that can be applied to improve the functional properties of emulsified meat products. The aim of this study was to evaluate the effect of HHP (100 and 200 MPa) on low-sodium mortadella produced with high content of mechanically deboned poultry meat (MDPM). Seven treatments were produced: FC (2.5% NaCl - control 1), F1-C (1.25% NaCl - control 2), F1-100 (1.25% NaCl and 100 MPa), F1-200 (1.25% NaCl and 200 MPa), F2-C (1.25% NaCl, 1.60% KCl), F2-100 (1.25% NaCl, 1.60% KCl, 100 MPa), and F2-200 (1.25% NaCl, 1.60% KCl, 200 MPa). Proximate composition, sodium content, emulsion stability, extraction yield of myofibrillar proteins, instrumental color, texture profile, and microstructure of the samples were evaluated. Pressurization and salt reduction did not affect chemical composition (moisture, fat and protein) of the samples, while HHP increased protein extraction, forming a more compact, homogeneous and better distributed gel, improving emulsion stability and increasing mortadella hardness. Therefore, this technique could effectively compensate the deterioration in the protein gel matrix caused by salt reduction. Studies are necessary to investigate the effects of HPP on sensory properties and lipid oxidation of mortadella.

Effect of amphiphilic nanoparticles and non-ionic surfactants on emulsion stability

Abstract To investigate the effect of amphiphilic nanoparticles and nonionic surfactants on the stability of emulsions, SiO2 nanoparticles were first locally surface modified with organosiloxanes of different carbon chain lengths to prepare amphiphilic nanoparticles with different hydrophobic properties, and then the effects of surfactant type and concentration, interfacial tension and its composite system with the amphiphilic nanoparticles on the stability of emulsions was investigated. The experimental results demonstrate, the OP-50 exhibits the most effective emulsification properties at a concentration of 0.1 %. However, the emulsion stability is significantly compromised. The emulsification effect of OP-50 with amphiphilic nanoparticles at a concentration of 0.1 % remained unaltered, while the emulsion stability was markedly enhanced compared to that of a single system. The modulus of expansion of OP-50 was 11.8 mN m−1, while that of OP-50 compounded with C8-10:1 was 120 mN m−1. The incorporation of modified nanoparticles with varying lengths of carbon chains was shown to effectively enhance the modulus of expansion of the oil–water interfacial interface. The results of this study are informative for the application of oil repellents in the mechanism of enhanced recovery.

Role of extractive compounds in emulsion stabilisation capacity of wood hemicelluloses

Abstract Hemicellulose-rich extracts obtained by pressurised hot water extraction of wood residues show promise as emulsion stabilisers. However, pressurised hot water extracts (PHWEs) from wood also contain lower molecular weight extractive components that may influence emulsion performance. This study investigated the effect of extractives on emulsion stability using PHWEs obtained from spruce and birch sawdust with or without solvent pre-extraction. The results indicated that extractives negatively affect the physical stability of emulsions in both spruce and birch and influence oxidative stability in spruce after prolonged storage. However, the roles of different extractives in emulsion performance require further investigation.

Enhanced Stability and Prolonged Insect-Repellent Action of Essential Oil-Loaded Nanostructured Lipid Carriers

Mosquito-borne diseases are a global health concern, necessitating effective and long-lasting insect repellents. This study investigated the physicochemical properties, stability, release kinetics, and efficacy of nanostructured lipid carriers (NLCs) and conventional emulsions (CEs) containing essential oils (NLC EOs) for insect-repellent applications. The droplet size of the CE was 18.46 ± 1.78 μm (Span 0.27 ± 0.06), while the NLC measured 136 ± 10.7 nm (PDI 0.26 ± 0.2) with a ζ-potential of –68 mV ± 2.2 mV (width 4.3 ± 0.1). EO incorporation did not significantly alter droplet size or ζ-potential. Gas chromatography–mass spectrometry confirmed an EO content of 8.57 ± 0.15 mg/mL in the CE EO and 7.75 ± 0.05 mg/mL in the NLC EO, with the NLC retaining a higher EO content over 90 days. Stability tests demonstrated consistent droplet sizes and ζ-potential for both formulations during storage. Release kinetics revealed diffusion-based release mechanisms, with the NLC providing a more sustained release than the CE. In a field test against mosquito species most frequently found in Greece, the NLC EO exhibited a significantly longer complete protection time (CPT) of 45 min, demonstrating more effective, long-lasting insect-repellent action. These findings revealed the NLC’s ability to retain volatile EO components efficiently, offering promising implications for long-lasting insect-repellent action.

FACS‐Sortable Triple Emulsion Picoreactors for Screening Reactions in Biphasic Environments

AbstractBiphasic environments can enable successful chemical reactions where any single solvent results in poor substrate solubility or poor catalyst reactivity. For screening biphasic reactions at high throughput, a platform based on microfluidic double emulsions can use widely available FACS (Fluorescence Activated Cell Sorting) machines to screen millions of picoliter reactors in a few hours. However, encapsulating biphasic reactions within double emulsions to form FACS‐sortable droplet picoreactors requires optimized solvent phases and surfactants to produce triple emulsion droplets that are stable over multi‐hour assays and compatible with desired reaction conditions. This work demonstrates such FACS‐sortable triple emulsion picoreactors with a fluorocarbon shell and biphasic octanol‐in‐water core. First, surfactants are screened to stabilize octanol‐in‐water emulsions for the picoreactor core. With these optimized conditions, stable triple emulsion picoreactors (>70% of droplets survived to 24 hr), produced protein in the biphasic core via cell‐free protein synthesis are generated, and sorted these triple emulsions based on fluorescence using a commercial FACS sorter at >100 Hz with 75–80% of droplets recovered. Finally, an in‐droplet lipase assay with a fluorogenic resorufin substrate that partitions into octanol is demonstrated. These triple emulsion picoreactors have the potential for future screening bead‐encoded catalyst libraries, including enzymes such as lipases for biofuel production.

Study on the stability and magnetically induced demulsification performance of Pickering emulsions based on arginine-modified lignin/Fe3O4 nanoparticles

In this study, four different arginine-modified lignin composites (Lig-Arg-x) were synthesized via the Mannich reaction, followed by the preparation of Lig-Arg-x/Fe3O4 magnetic nanoparticles (NPs) using hydrothermal reduction. The magnetic particles were characterized, and their emulsification properties were investigated. The highest grafting degree was achieved at a 1:1 M ratio of arginine to lignin. Pickering emulsions were formulated and Lig-Arg-x/Fe3O4 NPs as the emulsifier. The study examined the impact of arginine grafting degree, oil-to-water volume ratio, and nanoparticle concentration on emulsion stability and demulsification performance. Optimal emulsion stability, characterized by the smallest droplet size of 20.57 μm, was achieved with a 1:1 M ratio of lignin to arginine, a 7:3 oil-to-water volume ratio, and a nanoparticle concentration of 1.0 w/v%. Magnetic induction experiments demonstrated significant phase separation in the stable emulsion under a magnetic field, confirming the magnetic-induced demulsification capability of the composite particles. Oil displacement experiments demonstrated that Lig-Arg-x/Fe3O4 NPs modulate oil droplet diffusion via the Marangoni effect, indicating their potential for oil recovery applications. After three cycles, Lig-Arg-1/Fe3O4 NPs retained 80 % of their saturation magnetization, demonstrating strong reusability. This study showcases lignin-magnetite nanocomposites' versatility in stabilizing emulsions and exhibiting magnetic responsiveness, advancing demulsification and oil spill recovery technologies.

Investigation on the interfacial and emulsion stabilized behavior of dextran/ferritin/resveratrol composite nanoparticles

Glycation of ferritin provides a viable approach to enhance its physicochemical and functional properties. However, there is limited research on the interfacial adsorption properties of glycated ferritin-based colloidal particles. Therefore, this study selected recombinant human H-chain ferritin (rHuHF), rHuHF encapsulated with resveratrol (rHuHF–Res), and rHuHF–dextran glycoconjugates loaded with resveratrol (Dex–rHuHF–Res) as emulsifiers to investigate their interfacial adsorption properties. The results revealed that Dex–rHuHF–Res exhibited superior emulsifying properties and rheological behavior. It also increased the hydrophobicity of the microenvironment around Tyr and Trp residues, while hydrogen bonds, hydrophobic force, and salt bridge were identified as the most important intermolecular interactions. Dex–rHuHF–Res exhibited the biggest contact angle and lowest interface tension, which further reduced the diffusion (Kdiff) from the aqueous phase to the interface but promoted the penetration (Kp) and rearrangement (Kr) rates at the interface. Meanwhile, the emulsion stabilized by Dex–rHuHF–Res displayed excellent freeze-thaw stability, and Dex–rHuHF–Res can be more densely accumulated at the O/W interface to form an interface layer. These findings highlight the promising application of glycated ferritin in stabilizing Pickering emulsions, and deepen our understanding of the interplay among particle interaction, interface adsorption properties, and emulsion stability.

Flammulina velutipes protein-Flammulina velutipes soluble polysaccharide-tea polyphenols particles stabilized Pickering emulsions for the delivery of β-carotene

The delivery vehicles based on protein-polysaccharide-polyphenol are promising methods to encapsulate bioactive components with the aim of improving their solubility and bioavailability. In this study, we used Flammulina velutipes protein (FVP) and Flammulina velutipes soluble polysaccharides (FVSP) as raw materials and prepared FVP-FVSP and FVP-FVSP-TP composite particles loaded with tea polyphenols (TP), the high internal phase Pickering emulsions stabilized by FVP-FVSP and FVP-FVSP-TP for the delivery of β-carotene (BC) were created. FVP-FVSP-TP has more promise as Pickering emulsion stabilizer than FVP-FVSP because of the smaller particle size, proper contact angle, and lower surface tension. The optimal preparation conditions of the emulsion were 4 % particle concentration and 80 % oil phase volume fraction. The emulsions stabilized by FVP-FVSP and FVP-FVSP-TP were o/w emulsions. Compared to the emulsion stabilized by FVP-FVSP, the FVP-FVSP-TP stabilized emulsion had higher G′, G″ values and viscosity and showed better thermal, centrifugal, storage and oil oxidation stability. Moreover, FVP-FVSP-TP stabilized emulsions could further enhance the retention rate and bioaccessibility of TP and β-carotene. This study provides a theoretical basis for the application of FVP and FVSP in Pickering emulsions, and a reference for the fabrication of delivery vehicles to improve the stability and bioaccessibility of bioactive substances.

Myosin supramolecular self-assembly: The crucial precursor that manipulates the covalent aggregation, emulsification and rheological properties of myosin

The transformation of molecular conformation and self-assembly properties of myosin during the heating process at different ionic strengths (0.2 M, 0.4 M and 0.6 M NaCl) and its effect on rheological behavior and emulsification properties were investigated. Under incubation temperatures between 40 °C and 50 °C, myosin underwent a supramolecular self-assembly stage dominated by noncovalent forces (hydrogen bonding, ionic bonding and hydrophobic interactions). Higher ionic strength facilitated molecular rearrangement through enhanced swelling of myosin heads and head-to-head assemblies, which contributed to enhanced ordering and homogeneity of myosin covalent aggregates (above 60 °C) and manifested itself macroscopically as enhanced gel viscoelasticity and emulsion stability. In contrast, at lower ionic strength, the tail-to-tail assemblies of myosin led to the preferential formation of covalent cross-links in the tails, which resulted in the inability of molecular rearrangement and the formation of disordered aggregates and finally led to the deterioration of the gel and the destabilization of the emulsion. In conclusion, the supramolecular self-assembly behavior of myosin, as an intermediate process in myosin’s sol–gel transition, is crucial for the orderliness of myosin assemblies, gel network strengthening, and emulsion stability. The obtained insight provides a reference for the precise implementation of quality improvement strategies for meat products.

Cellulose nanocrystals-based Pickering emulsion with enhanced foliar adhesion and pH responsiveness for intelligent delivery of pesticides

Pickering emulsions stabilized by functionalized natural macromolecules have emerged with promising responsiveness for pesticide encapsulation and release. This study developed Pickering emulsions using amine-modified cellulose nanocrystals (ACNCs) as stabilizers. The resultant O/W ACNCs-Pickering emulsions (ACNCs-Pickering) exhibited long-term storage stability and showed increasing emulsion stability depending on the concentration of ACNCs. Imidacloprid (IMI) was subsequently loaded onto the ACNCs-Pickering to form the IMI@ACNCs-Pickering via the in-situ loading route. The release rate of IMI demonstrated a notable pH responsiveness. Moreover, the IMI@ACNCs-Pickering prepared with an ACNCs concentration of 3 wt% showed optimal performances. Its foliar adhesion on Chinese cabbage (Brassica rapa L.ssp.pekinensis) was significantly higher than that of the commercial IMI formulation (70 WS, Bayer®, LS200032) (DG). In detail, the pesticide residue for the IMI@ACNCs-Pickering was 3.8 folds to that for DG after spraying and washing for 10 min. Also, the green peach aphid mortality rate was 98.33 %, which was 1.1 folds higher than that of the DG group. The present work developed a Pickering emulsion-based fat-soluble pesticide formulation with excellent foliar adhesion, resistance to rainfall washout, and insecticidal effect. It provided a new option to ensure the sustainable development of green agriculture.

Interfacial structure modification and enhanced emulsification stability of microalgae protein through interaction with anionic polysaccharides

Microalgae protein (MP) have emerged as a focal point of research within food processing due to its nutritional value and foaming properties. However, its isoelectric point around pH 4 leads to it susceptible to collision, binding, and precipitation. Additionally, MP has poor emulsification properties and only shows stability under strongly alkaline conditions. This study investigated the effects of food-grade anionic polysaccharides (guar gum (GG), gum arabic (GA), low acyl gellan gum (LG), and pectin (PT)) on the molecular structure and emulsification properties of MP. Results indicated that these anionic polysaccharides enhanced the UV absorption of MP near 620 nm, especially at 14 % content, while fluorescence intensity decreased due to amino acid residues masking without structural changes. The addition of polysaccharides resulted in bimodal or multimodal particle size distributions, with LG and PT showing larger particle sizes. At pH 4, negatively charged polysaccharides formed stable complexes with near-neutral MP, improving solution stability via electrostatic repulsion and diminishing turbidity. The droplet distribution analysis indicated that higher anionic polysaccharide ratios (1:4, 1:2, and 1:1) correlated with smaller droplet sizes and increased emulsion stability. Zeta-potential measurements revealed negative charges for emulsions, with LG-MP and PT-MP complexes displaying higher absolute values (15.0 to 20.7 mV) compared to GG-MP and GA-MP complexes, indicating superior stability. Storage stability analysis showed that LG-MP and PT-MP complexes stabilized emulsions had minimal delamination over two weeks. Rheological assessments showed that increasing GG and GA contents from 14 % to 50 % had negligible effects on apparent viscosity, while LG-MP (1:1) complexes stabilized emulsion displayed higher viscosity compared to PT-MP emulsions. Frequency sweep results showed that GG-MP, GA-MP, and LG-MP emulsions had greater elastic moduli (G') than viscous moduli (G"), indicating elastic behavior, whereas PT-MP emulsions transitioned from liquid-like to solid-like behavior as frequency increased. This study illustrates the advantages of high LG and PT content in preventing particle aggregation and enhancing emulsion stability, providing a theoretical and practical foundation for MP applications in food processing.

Dry fractionation of sunflower press cake as tool to improve its technofunctional properties

Depending on the oil production technology, at least 60% of the oilseeds input such as sunflower, pumpkin or canola remain as by-product, which is usually denoted as press cake (PC) and contains a significant amount of fiber and protein. Its further valorization in food requires knowledge on the technofunctional properties of the press cake and on possibilities for improving its value. Aim of the current study was to evaluate the effect of two separation techniques, namely targeted sieving and air classification, on composition, and physical as well as technofunctional properties of fractions of sunflower press cake previously milled to < 1.0 mm or < 2.0 mm. It is evident for both separation techniques that fines fractions obtained by using smaller sieves or lower air volume flow showed an increased protein content, with a protein enrichment factor of up to 1.47. Using PC < 2.0 mm as raw material, protein separation efficiency, a combined measure for protein content and yield, was higher after separation by air classification. Whereas protein solubility was not affected by the particle size distribution of the separated fractions, emulsion activity and emulsion stability were improved especially for the small particle fractions separated from PC < 2.0 mm.

Cold plasma reengineers peanut protein isolate: Unveiling changes in functionality, rheology, and structure.

This study investigates the effects of cold plasma (CP) treatment on peanut protein isolate (PPI), focusing on functionality, rheology, and structural modifications across various treatment times (0, 90, 180, 270, 360, and 450 s) and voltages (120, 140, and 160 kV). Key findings include a significant increase in solubility from 9.99 mg/mL to 15.98 mg/mL, as well as 161.07 % enhanced water-holding capacity (WHC) and 448.45 % oil-holding capacity (OHC). CP treatment also improved foaming capacity (FC) to 186.46 % and increased emulsion capacity (EC) and emulsion stability (ES) by 185.90 % at 160 kV. Rheological analysis showed shear-thinning behaviour, with viscosity decreasing as the shear rate increased-higher voltages (140 kV and 160 kV) further reduced viscosity, indicating lower resistance to flow. Additionally, CP-treated PPI exhibited viscoelasticity, with increased storage and loss moduli at higher frequencies, indicating greater stiffness. Spectroscopic studies demonstrated shifts in the protein's secondary structure, altering the balance among alpha-helix, beta-sheet, and random coil components, which highlights CP's role in reengineering PPI. FTIR-ATR spectra revealed reductions in the 3200-3400 cm-1 range, suggesting changes in protein backbone vibrations and hydrogen bonding. Particle size analysis showed significant increases, especially at higher voltages and longer treatment times, stabilizing after 270 s. Zeta potential assays indicated a gradual decrease in negative surface charge, suggesting enhanced protein aggregation. Overall, CP treatment significantly improves the functional and rheological properties of PPI while inducing structural changes, making it more suitable for applications in the food and pharmaceutical industries.

CHARACTERIZATION OF CAKES PRODUCED WITH DIFFERENT LEGUME AQUAFABA

This study investigates the potential of aquafaba, derived from various legumes including white chickpeas, black chickpeas, white beans, and red beans, as an egg substitute in cake production. Aquafaba samples were analyzed for physicochemical properties and functional characteristics at different pH levels. The results revealed that the foam and emulsion properties of all aquafaba samples at pH 3 were superior to those obtained at other pH values. Specifically, at pH 3, foam capacity values were approximately 238.74±28.54%, 231.25±26.52%, 237.50±17.68%, and 112.50±17.68% for aquafaba derived from white chickpeas, black chickpeas, white beans, and red beans, respectively. Aquafaba derived from white chickpeas demonstrated the highest foam stability at pH 3 (92.43±0.61%), followed by black chickpeas (86.96±3.30%). Similarly, emulsion capacity at pH 3 was highest for aquafaba derived from white chickpeas (41.14±11.73%), followed by black chickpeas (65.33±26.28%), white beans (28.94±37.69%), and red beans (49.65±9.57%). Emulsion stability was measured as 100% for aquafaba derived from white chickpeas, black chickpeas, and white beans at pH 3, with slightly lower values observed for aquafaba from red beans. Furthermore, aquafaba derived from different legumes exhibited varying protein contents at pH 3, ranging from 17.75±0.05% to 19.20±0.09%. Cake production with aquafaba as an egg substitute was conducted at pH 3, with analyses including moisture, ash, protein, fat, color, texture, specific volume, weight loss, and sensory evaluation. Results indicate the potential of aquafaba as a versatile egg substitute in cake formulations, with promising foam and emulsion properties, protein content, and sensory attributes.

Enhancing the emulsification performance of hempseed protein hydrolysate through the incorporation of sugar beet pectin: Role of interaction mechanism and interfacial behavior.

Effects of incorporating sugar beet pectin (SBP) at various pH levels (3.0-7.0) on the conformation, interfacial characteristics, and emulsification performance of hempseed protein hydrolysate (HPH) were explored. The introduction of SBP stimulated the conversion of protein conformation from α-helix and random coil into β-sheet. Besides, the incorporated SBP led to noticeable deformation and disruption of the original granular structure of HPH, and caused a remarkable reduction in surface hydrophobicity and intrinsic fluorescence intensity. FTIR analysis and pH-dependent molecular docking verified that hydrogen bonding, hydrophobic interactions, and electrostatic interactions predominantly drove the interaction between HPH and SBP. Overall, the interaction of HPH with SBP limited protein diffusion to the interface but facilitated their rearrangement at the interface, ultimately contributing to the development of highly viscoelastic interfacial layers with reinforced intermolecular interactions. Consequently, the emulsifying activity and emulsion stability within the acidic pH range (3.0-6.0) were significantly improved by SBP binding, notably at pH5.0. Furthermore, within this pH range, HPH-SBP emulsions exhibited smaller droplet sizes with a more homogeneous distribution and stronger electrostatic repulsion relative to HPH emulsions; yet, the apparent viscosity and elastic modulus of HPH-SBP emulsions were conspicuously elevated in the presence of SBP, conducing to emulsion stabilization.

Optimization design of asphalt emulsion with rejuvenator towards a uniform distribution inside the damaged porous asphalt mixture for a better ravelling resistance

Porous asphalt (PA) pavements usually meet the ravelling disease after opening to traffic for several years. Spraying surface treatment (ST) emulsion to PA pavement is a feasible preventive maintenance technology to alleviate this problem. However, the void clogging, nonuniform distribution and low diffusion efficiency of ST residue might hinder its widespread application. Therefore, this study aims to optimize the ST emulsion formula to improve the ravelling resistance of damaged PA. Usages of adding rejuvenators into ST emulsions were discussed. The orthogonal design method was used to determine the appropriate parameter values for preparing rejuvenator emulsions. The viscosity, contact angle and water boiling tests were then conducted to determine the optimal dosage of rejuvenator emulsion within ST emulsion. Cantabro abrasion test was performed to verify the ravelling resistance of damaged PA mixtures treated with optimized ST. Results showed that a stable and homogeneous rejuvenator emulsion could be produced by precisely controlling the PH value, emulsified temperature and emulsifier dosage. Adding rejuvenator emulsions to ST emulsions significantly improved the wettability. The optimal dosages of aromatic oil and tall oil emulsions are 10% and 5% by mass of ST emulsions. Optimized ST containing rejuvenator emulsions showed better ravelling resistances than pure asphalt emulsion.

Cross-linked chitosan encapsulated hollow mesoporous silica nanoparticle: A dual-functional smart nanocapsule design for targeted corrosion inhibition and controlled emulsification

Research on stimuli-responsive micro-nanocontainers has gained attention for targeted corrosion inhibition and controlled emulsification-demulsification in oil recovery. However, existing nanocontainers face issues like irreversible drug release and limited functionality. This study presents a multi-functional nanocontainer design with reversible drug release and emulsification-demulsification capabilities. The fabricated nanomaterial BTA@HMSNs-CS, i.e., hollow mesoporous silica nanocontainers (HMSNs) loaded with 1H-Benzotriazole (BTA) and coated with crosslinked chitosan (CS), can transport BTA to corrosive areas in oil wells for targeted corrosion inhibition, and emulsify oil droplets in deep underground oil reservoirs for enhanced recovery. The imine bonds within the cross-linked CS layer demonstrate sensitivity to pH variations, dynamically adjusting the CS polymerization degree. This mechanism controls the BTA release from HMSNs-CS, achieving long-term corrosion inhibition of metal. When reaching deep underground oil reservoirs, the HMSNs-CS nanocontainers exhibit stable adsorption at the oil-water interface, preventing oil droplet aggregation and reducing the oil-water interfacial tension. This results in the formation of stable Pickering emulsions, facilitating demulsification in acid and emulsification in neutral/alkaline environments, and ultimately ensuring improved oil recovery efficiency. In this study, the developed nanomaterial exhibits dual-functions of corrosion inhibition and emulsification, offering an integrated strategy for metal protection and oil recovery in oil and gas operation.