Pickering High Internal Phase Emulsions Research Articles

Insight into oil-water interfacial behaviors of whey protein isolate and sterol towards stabilizing high internal phase Pickering emulsion gels

This investigation elucidated stabilization of high internal phase Pickering emulsion gels (HIPPEGs) on the basis of oil-water interfacial adsorption properties of particles. The particles were prepared by whey protein isolate (WPI) and two structurally different sterols, including ergosterol (ES) and γ-oryzanol (γS). Initially, oil-water interfacial adsorption properties were improved in the presence of sterol. And WPI-γS exhibited higher contact angle and lower dynamic interfacial tension than WPI-ES. Quartz crystal microbalance with dissipation monitoring measurement further proved that adsorption mass and viscoelasticity of WPI-γS was higher than those of WPI-ES. Furthermore, WPI-sterol HIPPEGs showed lower average particle size and moisture content, higher absolute value of ζ-potential than WPI-stabilized HIPPEGs. Apparent viscosity, storage modulus and loss modulus of WPI were improved after the addition of sterol. Moreover, WPI-γS HIPPEGs exhibited higher stabilities and viscoelasticity than WPI-ES HIPPEGs. Additionally, compared with WPI-stabilized HIPPEGs, WPI-γS-loaded HIPPEGs showed shorter relaxation time and more uniform color distribution, indicating that droplet flow was restricted and more uniform, followed by WPI-ES-loaded HIPPEGs. Finally, super-resolution microscope results exhibited that sterol inhibited emulsion droplets aggregation due to steric hindrance. HIPPEGs stabilized by WPI-γS showed more homogeneous and smaller droplets than WPI-ES-loaded HIPPEGs. This work provided a theoretical support for stable HIPPEGs formed with protein-sterol particles, which would be applied to replace trans fats and cholesterol in various food products.

High internal phase Pickering emulsions stabilised by ultrasound-induced soy protein-β-glucan-catechin complex nanoparticles to enhance the stability and bioaccessibility of curcumin

Aims To evaluate the potential applications of soy protein–glucan–catechin (SGC) complexes prepared with different ultrasound times in stabilising high internal phase Pickering emulsion (HIPPE) and delivering curcumin. Methods The SGC complexes were characterised by particle size, morphology, zeta potential, Fourier transform infra-red, and fluorescence spectroscopy. Formation and stability of curcumin emulsions were monitored by droplet size, microstructure, rheological property, lipid oxidation, and in vitro digestion. Results Short-time ultrasound-induced complexes (SGC-U15) exhibited a small size and wettability of ∼82.5°. The chemical stability and bioaccessibility of curcumin was greatly improved by SGC-U15-stabilised HIPPEs, even after 70 days of storage, heating at 100 °C for 30 min, ultraviolet irradiation for 120 min, and in vitro digestion, owing to the formation of elastic gel-like structure at the oil/water interfaces. Conclusion Our findings may contribute to the design of emulsion-based delivery systems using ultrasound-induced protein–polysaccharide–polyphenol complexes.

High internal phase Pickering emulsions stabilized by modified sturgeon myofibrillar protein for quercetin delivery

In this study, the modified sturgeon myofibrillar protein was prepared by the combination of malondialdehyde and ultrasonic induction and used as the emulsifier to form a stable high internal phase Pickering emulsion (HIPPEs) with internal phase up to 75%. The results showed that combined modification reduced the fluorescence intensity, enhanced the surface hydrophobicity, changed the secondary structure, and made the protein particles smooth. The confocal laser scanning microscopy confirmed the formation of a stable HIPPEs. The interfacial tension and rheological properties of protein stabilized HIPPEs were improved by the combined modification and the encapsulation efficiency of quercetin reached 89.32%. In vitro digestion showed that the combined modified protein-stabilized HIPPEs significantly improved the rate of lipid digestion and the bioavailability of quercetin while reducing the degradation of quercetin. The findings indicated that the utilization of modified sturgeon myofibrillar protein to stabilize HIPPEs hold significant promise for various biological applications, owing to its capacity as a carrier for the regulated discharge of bioactive agents.

High internal phase Pickering emulsions stabilized by ε-poly-l-lysine grafted cellulose nanofiber for extrusion 3D printing

An effective method for preparing food-grade three-dimensional (3D) printing materials was the use of highly concentrated oil-in-water emulsions. This research reported 3D printable materials constructed from food-grade high internal phase Pickering emulsions (HIPPEs) that were stabilized by ε-poly-l-lysine grafted cellulose nanofiber (ε-PL-TOCNs). The ε-PL-TOCNs were prepared via ε-poly-l-lysine grafting of 2, 2, 6, 6-tetramethylpiperidine-N-oxyl (TEMPO)-oxidized cellulose (TOC) and the successive mechanical treatment. Subsequently, the chemical structure, microstructure and surface properties of ε-PL-TOCNs were characterized. The results showed that the prepared ε-PL-TOCNs had excellent dispersion performances, cationic properties brought by amino groups, and hydrophilic/hydrophobic functions of chain structure, which confirmed the feasibility of preparing HIPPEs. The HIPPEs with an internal phase volume fraction of 82 % were obtained at 0.8 wt% ε-PL-TOCNs concentration and pre-emulsification followed by continuous oil feeding. The HIPPEs' storage stability, morphology, and rheological behavior were further discussed. The ultra stable HIPPEs with apparent shear-thinning behavior and high solid viscoelasticity were successful produced, which was suitable for 3D printing. This work expanded the application of nanocellulose in emulsions field and provided a new thinking to prepare food-grade 3D printable materials and porous foam.

Molecular mechanisms affecting the stability of high internal phase emulsions of zein-soy isoflavone complexes fabricated with ultrasound-assisted dynamic high-pressure microfluidization

In this study, zein-soy isoflavone complex (ZSI) emulsifiers were fabricated using ultrasound-assisted dynamic high-pressure micro fluidization to stabilise highinternal phase pickering emulsions. Ultrasound-assisted dynamic high-pressure micro-fluidization enhanced surface hydrophobicity, zeta potential, and soy isoflavone binding capacity, while it decreased particle size, especially during ultrasound and subsequent microfluidization. The treated ZSI could produce small droplet clusters and gel-like structures, with excellent viscoelasticity, thixotropy and creaming stability owing to their neutral contact angles. Ultrasound and subsequent micro fluidization treatment of the ZSI complexes were highly effective in preventing droplet flocculation and coalescence after long-term storage or centrifugation due to their higher surface load, thicker multi-layer interfacial structure, and stronger electronic repulsion between the oil droplets. This study provides insights and extends our current knowledge of how non-thermal technology affects the interfacial distribution of plant based particles and the physical stability of emulsions.

Whey protein-tannic acid conjugate stabilized high internal phase Pickering emulsions: Interfacial stability based on covalent crosslinking

Protein-stabilized high internal phase Pickering emulsions (HIPEs) have potential usage in food and cosmetic fields. However, the poor interfacial activity of proteins in HIPEs is still a key bottleneck. In this work, whey protein (WP)-tannic acid (TA) conjugates by covalent crosslinking were used to fabricate HIPEs, and then the emulsifying ability and stability of HIPEs were also studied. The result indicated that covalent bonds formed between WP and TA. WP-TA conjugates had better oil-water interfacial activities and more suitable wettabilities than free WP. WP-TA conjugate stabilized HIPEs had a narrower size distribution, a more compact droplet structure and a denser gel network compared with free WP stabilized HIPEs, especially at high TA mass ratios and alkaline conditions. At the same time, the conjugates stabilized HIPEs exhibited better stability against heat treatment and centrifugation. Covalent crosslinking in WP-TA conjugates formed network based on TA molecules as bridges among emulsion droplets and played an important role in stabilizing HIPEs. This study expects to provide a new perspective for investigating the stabilizing mechanism of protein-polyphenol conjugate stabilized HIPEs.

Studies on stabilized mechanism of high internal phase Pickering emulsions from the collaboration of low dose konjac glucomannan and myofibrillar protein

In this study, the effects of different concentrations (0%, 0.25%, 0.5%, 1%, 1.5%, w/v) of konjac glucomannan (KGM) on the structure and interfacial adsorption of myofibrillar protein (MP) and the mechanism of co-emulsification of high internal phase Pickering emulsions (Pickering HIPEs) by KGM and MP were investigated. The results showed that for interfacial MPs, KGM addition promoted MP structure unfolding and improved MP wettability with a three-phase contact angle from 73.69° (control) to 89.41° (0.5% KGM), thereby lowering the energy barriers to MP penetrating and rearranging at the interface. Furthermore, the adsorption kinetics and protein adsorption percentage (AP%) indicated that KGM (≤1%) facilitated the adsorption of MP from the aqueous phase to the oil-water interface. For MP in the aqueous phase, KGM induced a denser MP network structure by promoting “concentrated” MP and connecting MP through hydrogen bonding, which formed a stronger spatial site resistance and hindered oil droplet aggregation. KGM (≤1%, especially 0.5%) resulted in reduced droplet size, relaxation time (T2), lipid oxidation, and improved storage stability and energy storage modulus of Pickering HIPEs. However, the competitive adsorption of KGM (>1%) significantly decreased the interface MP, and the formation of continuous KGM hydrogel formed an unaggregated MP network structure, decreasing the emulsion performance further. Overall, KGM could modulate the physical properties of MP-stabilized Pickering HIPEs by altering the interfacial adsorption and network structure.

Fabrication of Poly(ε-caprolactone)-embedded Lignin-Chitosan Nanocomposite Porous Scaffolds from Pickering Emulsions.

Poly(ε-caprolactone) (PCL)-incorporated lignin-chitosan biomass-based nanocomposite porous scaffolds have been effectively prepared by templating oil-in-water Pickering high internal phase emulsions (HIPEs). PCL is dissolved in oil and chitosan and lignin nanoparticles originate in water. The continuous phase of the emulsions is gelled by cross-linking of chitosan with genipin and then freeze-dried to obtain porous scaffolds. The resulting scaffolds display interconnected and tunable pore structures. An increase in PCL content increases the mechanical strength and greatly reduces the water absorption capacity of the scaffolds. Scaffolds loaded with the anti-bacterial drug enrofloxacin show a slow drug release profile, adjustable release rate, and favorable long-term anti-bacterial activity. Moreover, Pickering emulsion templates with suitable viscosity are used as 3D printing inks to construct porous scaffolds with personalized geometry. The results imply that the simplicity and versatility of the technique of combining freeze-drying with Pickering HIPE templates is a promising approach to fabricate hydrophobic biopolymer-incorporated biomass-based nanocomposite porous scaffolds for biomedical applications.

High-internal phase Pickering emulsion stabilized by crystals of nobiletin: assembly of supramolecular metal-polyphenolic coordination complexes for surface coating.

High internal phase Pickering emulsion has attracted extensive attention due to its unique properties, and has broad application prospects in the food field, such as as a fat replacer, packaging and delivery of nutrients or probiotics, and 3D printing of food. However, efficient and edible high-internal phase Pickering stabilizer is still a persistent challenge for food scientists. Herein, the nobiletin (NOB) was selected as a model substance, the particle physicochemical properties (droplet size, rheological behavior, and transmission profile) showed that supramolecular metal-polyphenolic coordination networks could suppress the ripening and growth of crystals on the oil-water interface. When the ratio of tannic acid (TA) and Fe3+ was 3:1, the crystallization growth of NOB could be effectively inhibited. Due to the reduction of energy steric hindrance in the adsorption process, the resulting NOB-TA3 -Fe3+ 1 (NT3 Fe1 ) nanoparticles had the greatest potential to extend emulsion storage time. This particle could stabilise a high-internal phase emulsion, of which the oil phase was 80%, for at least 30 days and eventually lead to high system viscosity. The findings in this work provided a novel selection of healthy emulsifiers as well as an effective emulsion delivery system for hydrophobic and crystalline nutrients. This article is protected by copyright. All rights reserved.

Covalent Bond Interfacial Recognition of Polysaccharides/Silica Reinforced High Internal Phase Pickering Emulsions for 3D Printing.

Significant challenges remain in designing sufficient viscoelasticity polysaccharide-based high internal phase Pickering emulsions (HIPPEs) as soft materials for 3D printing. Herein, taking advantage of the interfacial covalent bond interaction between modified alginate (Ugi-OA) dissolved in the aqueous phase and aminated silica nanoparticles (ASNs) dispersed in oil, HIPPEs with printability were obtained. Using multitechniques coupling a conventional rheometer with a quartz crystal microbalance with dissipation monitoring, the correlation between interfacial recognition coassembly on the molecular scale and the stability of whole bulk HIPPEs on the macroscopic scale can be clarified. The results showed that Ugi-OA/ASNs assemblies (NPSs) were strongly retargeted into the oil-water interface due to the specific Schiff base-binding between ASNs and Ugi-OA, further forming thicker and more rigid interfacial films on the microscopic scale compared with that of the Ugi-OA/SNs (bared silica nanoparticles) system. Meanwhile, flexible polysaccharides also formed a 3D network that suppressed the motion of the droplets and particles in the continuous phase, endowing the emulsion with appropriately viscoelasticity to manufacture a sophisticated "snowflake" architecture. In addition, this study opens a novel pathway for the construction of structured all-liquid systems by introducing an interfacial covalent recognition-mediated coassembly strategy, showing promising applications.

High internal phase pickering emulsions stabilized by ODSA-functionalized cyclodextrin metal-organic frameworks for extrusion 3D printing application

Cyclodextrin metal-organic frameworks (CD-MOFs) are novel ordered porous materials with high adsorption and interfacial stabilization. Herein, oil-in-water emulsions stabilized by octadecenylsuccinic anhydride (ODSA) modified CD-MOFs (OCMs) with a volume fraction of 0.8 were prepared. A contact angle of 92° was achieved when 5 wt% ODSA was added to OCMs, which promoted the stabilization of OCMs-emulsions with homogeneous and spherical droplets. Moreover, the emulsion possessed a small droplet size of 7–9 μm (d4,3), long-term storage stability and flocculation resistance. At the pH range of 10–12, the emulsions had a more desirable structure with a gel-like elastic network and a dense particle layer covered onto the droplets, which were verified by SEM and cryo-SEM. The 2D cross-linked particle film at the water-oil interface and the 3D cross-linked gel-like particle network in the continuous phase synergistically improved the stability of coalescence and flocculation of the OCMs-HIPPEs. Afterwards, the OCMs-HIPPEs with no discernible oil were used as printing ink, which had no droplet coalescence in the freeze-thaw and showed high 3D printing quality and shape retention. Overall, this study demonstrates that the ODSA-modified CD-MOFs with favorable properties may be used to fabricate high-quality edible HIPPEs for extrusion 3D printing ink.

Soy protein isolate-citrus pectin-gallic acid ternary composite high internal phase Pickering emulsion for delivery of β-carotene: Physicochemical, structural and digestive properties

The structure properties, stability and β-carotene slow-release mechanism of soybean protein isolate-citrus pectin-gallic acid complex (SPI-CP-GA) stabilized high-internal phase Pickering emulsion (HIPPE) were investigated. The results showed that compared with the SPI-CP binary complex, the turbidity of the SPI-CP-GA ternary complex increased from 2.174 ± 0.001 to 3.027 ± 0.001, the surface wettability was increased, the infrared peaks was blue-shifted, changed from hydrophilic to hydrophobic, and the equilibrium interfacial tension of particles increased from 10.77 ± 0.02 mN/m to 13.46 ± 0.03 mN/m, the complex was more stable. When the GA was 2.0 mg/mL, the encapsulation efficiency of β-carotene was higher. With increased GA concentration and oil phase volume fraction (φ), the apparent viscosity and viscoelastic behavior of HIPPE performed well, forming a stable gel network structure. After 30 days of storage, there was no oil separation in the sample group with GA concentration of 2.0 mg/mL and φ = 0.7, and the stability was strong. After gastrointestinal digestion, the particle size of the HIPPE decreased from 13.51 ± 0.86 μm to 7.70 ± 0.68 μm, the free fatty acid (FFA) release rate was 22.03%, and the bioaccessibility of β-carotene was 6.67 ± 0.19%, and the sustained-release effect was obvious. These results indicated that the SPI-CP-GA ternary complex is a potential stabilizer for HIPPE, and providing theoretical guidance for the design of protein-polysaccharide-polyphenol stabilized HIPPE.

Plant protein-based high internal phase Pickering emulsions: Functional properties and potential food applications

Plant proteins are of interest to the food science, biopharmaceutical, and environmental engineering fields due to their excellent surface properties, biocompatibility, biodegradability, biosafety, and sustainability. However, there are still numerous challenges to overcome before they can be widely used in industrial production. To this end, this paper details the factors affecting the structure and performance of high internal phase Pickering emulsions (HIPPEs) made with plant proteins as stabilizers. Moreover, strategies to stabilize HIPPEs by plant-based proteins are reviewed. Finally, the emerging research trends focusing on the potential applications of HIPPEs in the food industry are highlighted, particularly as a substitute for trans and saturated fats, nutrient encapsulation and delivery, 3D printing foods and complex porous material design. This review not only provides cutting-edge knowledge on the construction of stable plant protein HIPPEs, but also lays a theoretical basis for their industrial production.

Preparation of high internal phase Pickering emulsion by centrifugation for 3D printing and astaxanthin delivery

Oil in water high internal phase Pickering emulsion (HIPEs) stabilized by edible colloid particles have attracted considerable attention for three-dimensional (3D) printing and delivery of a hydrophobic bioactive. In this paper, a facile route for preparing oil in water HIPEs was demonstrated, only requiring centrifuging gliadin/gelatinized starch nanocomposites (G/SNPs) stabilized pre-emulsions. The surface properties of G/SNPs were engineered which helped prevent oil coalescence during centrifugation, while obtaining HIPEs with oil phase fractions up to 77.3%, simultaneously. The resultant HIPEs exhibited shear-thinning behavior with high solid viscoelasticity. Furthermore, HIPEs with internal phase fraction above 80% were successfully prepared simply by adjusting the ionic strength. The HIPEs with suitable rheology properties for 3D printing were obtained, and the enhanced viscoelasticity and thixotropic recovery could be attributed to the electrostatic shielding under higher ionic strength. In addition, the light stability and bioaccessibility of astaxanthin were significantly improved by HIPEs, and more than 90% astaxanthin was retained after heating at 95 °C for 30 min. These results proved a new route for producing HIPEs with improved performance, opening new possibilities for manufacturing future food and delivery of hydrophobic bioactive molecules.

Preparation and application of natural protein polymer-based Pickering emulsions

Abstract Emulsification is the effect of a liquid being uniformly dispersed as tiny droplets in another liquid that is immiscible. Traditional emulsification requires the addition of suitable surfactant to stabilize the emulsion. When the surfactant molecules are replaced by solid particles, the emulsion is known as Pickering emulsions (PEs). PEs with dispersed phase volume fraction above 74% are also named high internal phase Pickering emulsions (HIPPEs). The use of solid particles of natural origin allows PEs to be highly physically stable, environmentally compatible, and biodegradable compared to traditional emulsions. Among them, protein-based solid particles are well suited to stabilize PEs for their great emulsification properties and nutritional value. In this article, we reviewed the preparation of different forms of proteins and their emulsion stabilization properties and summarized the applications of protein-based PEs in various fields, including food, biomedicine, porous materials, biodegradable packaging films, sewage treatment, 3D printing, etc.

High internal phase Pickering emulsion stabilized by zein-tannic acid-sodium alginate complexes: β-Carotene loading and 3D printing

Food-grade compound-stabilized high-internal-phase Pickering emulsions (HIPEs) have received widespread attention in food industry and functional foods. However, challenges are still there regarding the inclusion of active substances and quickly processing molding for food manufacturing. Herein, we used zein, tannic acid (TA) and sodium alginate (SA) to synergistically increase the stability of HIPEs. Owing to electrostatic, hydrophobic and hydrogen-bond interactions among protein, polyphenol and polysaccharide, Zein-TA-SA composite particles-stabilized HIPEs (ZTS-HIPEs) exhibited good pH and ionic strength stability. The HIPEs could further be used to load and solubilize β-carotene, while significantly improved the retention of β-carotene in different environments. Simulated in vitro digestion experiments showed that the release rate of free fatty acids and bioaccessibility of β-carotene in HIPEs were significantly improved, indicating that HIPEs might achieve efficient delivery of β-carotene in the gastrointestinal environment. In addition, the ZTS-HIPEs could be 3D printed as food-grade inks due to their good rheological properties as the printed models showed good precision and stability. In summary, the ZTS-HIPEs prepared in this study could be used not only as an effective delivery carrier of β-carotene, but also as a potential ink for 3D printing. The research findings in this study are expected to provide novel insight on HIPEs for nutrition delivery systems and future food manufacturing.

Construction of high internal phase Pickering emulsions using cold plasma modified soy protein isolate-proanthocyanidin complex

Protein-based high internal phase Pickering emulsions (HIPPEs) feature numerous multi-functionalities and widespread applications. However, the direct use of native proteins for the constructions of HIPPEs is limited since it is fragile under various conditions. Here, cold plasma was used to modify soy protein isolates (SPI) to improve their surficial properties. Meanwhile, proanthocyanidins (PA) were applied to interact with cold plasma-treated SPI to form complex. Furthermore, the well-prepared SPI-PA complex was used to construct novel HIPPEs. Results showed cold plasma treatment significantly improved the functionalities of SPI, which were confirmed by surface hydrophobicity (H0 ＜ 500), sulfhydryl (SH) groups and spectral analysis. Further, the emulsification and oxidation resistance of cold plasma treated SPI were enhanced after forming complex with PA. Soybean oils can be stabilized by SPI-PA complexes to form HIPPEs with a lipid oxidation inhibition rate of ＞ 65%, creaming index (CI) ＞ 80%, excellent rheological properties and better stability compared with conventional emulsion systems. Overall, this SPI-PA complexes provides a unique approach to improve the emulsification and oxidation resistance to engineer HIPPEs with versatile applications.

Fabrication and characterization of high internal phase Pickering emulsions based on pH-mediated soy protein-epigallocatechin-3-gallate hydrophobic and hydrophilic nano-stabilizer

This study describes the feasibility of O/W High internal phase Pickering emulsions (HIPPEs) with an oil volume fraction of 0.82 stabilized by using SECNs at pH 3.0, 6.0 and 9.0. Soy protein isolate (SPI) was converted into the molten globule (MG) state at pH 3.0 and 9.0, modified by (−)-epigallocatechin-3-gallate (EGCG), and heated to obtain SPI-EGCG composite nanoparticles (SECNs). Results obtained demonstrated that with the introduction of EGCG in soy protein nanoparticles (SPNs) and increase in pH from 3.0 to 9.0, the particle distribution and tertiary structures of these nanoparticles were altered, along with decrease in surface hydrophobicity (H0), and enhancement of particle wettability and antioxidant activity. The structure of SPNs at different pH showed that there were two kinds of HIPPEs stabilizing mechanisms: nonshared multilayers (at pH 3.0 and 6.0) and mono-/shared layers (at pH 9.0). These findings provide insights into the design of protein-polyphenol nanoparticles stabilized HIPPEs suitable for the formulation of functional foods.

Understanding the structure, interfacial properties, and digestion fate of high internal phase Pickering emulsions stabilized by food-grade coacervates: Tracing the dynamic transition from coacervates to complexes

Although protein-polysaccharide complexes have shown tremendous potential in stabilizing high internal phase Pickering emulsions (HIPPEs), it is unclear whether coacervates have the same potential to be used as effective Pickering stabilizers. In this study, HIPPEs were prepared by ovalbumin (OVA)-pectin (PE) coacervates during the transition from coacervates to complexes. The results showed that enhanced OVA-PE interactions significantly affected the wettability and surface-tension reduction ability of the OVA-PE coacervates. At pH 2, the coacervate-stabilized HIPPEs exhibited smaller oil droplet sizes (21.3±2.3 μm), tighter droplet packing, and finer solid-like structures through the bridging of droplets and the generation of stronger gel-like network structures to prevent coalescence and lipid oxidation. The gastrointestinal digestion results proved that the OVA-PE coacervates promoted lipid hydrolysis and improved the bioaccessibility (from 19.7±0.7% to 36.5±2%) of curcumin-loaded HIPPEs. Our work provides new ideas for the development of biopolymer particles as effective Pickering stabilizers in the food industry.

High Internal Phase Pickering Emulsion Stabilized by Lipase-Coated ZIF-8 Nanoparticles towards Recyclable Biphasic Biocatalyst

High internal phase Pickering emulsion (Pickering HIPE) stabilized by enzyme-decorated metal-organic frameworks (MOFs) nanoparticles is developed for biphasic biocatalysts to enhance lipase catalysis and recycling. Specifically, enzyme decorated nanoparticles are prepared via ZIF-8 physisorption of a model lipase Candida antarctica Lipase B (CALB), named ZIF-8@CALB, to be both Pickering stabilizer and catalytic sites. An oil-in-water (o/w) Pickering HIPE with oil/water volume ratio of 3 could then be fabricated by homogenizing p-nitrophenyl palmitate (p-NPP) n-heptane solution into the ZIF-8@CALB aqueous dispersion. The biocatalytic hydrolysis of p-NPP is conducted by just standing the biphasic system at room temperature. The Pickering HIPE system achieves a product conversion of up to 48.9% within 0.5 h, whereas the p-NPP n-heptane solution system containing free CALB only achieves a stable product conversion of 6.8% for the same time. Moreover, the ZIF@CALB could be recovered by a simple centrifugation at 800 rpm, and then reused in the next cycle. The hydrolysis equilibrium conversion rate of p-NPP keeps over 40% for all 8 cycles, reflecting the high catalytic efficiency and recyclability of the Pickering HIPE. This study provides a new opportunity in designing Enzyme-MOFs-based Pickering interfacial biocatalyst for practical applications.