Kinetic and Oxidative Stability of Oil-in-Water Pickering Emulsions Stabilized by Lysozyme-Ferulic Acid Conjugates

Novel food-grade water-in-water Pickering emulsions for encapsulation and delivery of hydrophilic bioactives.

Curcumin exhibits excellent bioactive potential, but its practical applications in functional foods are limited. In this study, novel food-grade water-in-water (W/W) Pickering emulsions constructed by maltodextrin/pullulan (MD/PUL) were developed to encapsulate and deliver of aqueously dispersible curcumin nanocomplex. Cellulose nanocrystals (CNCs) prepared by TEMPO oxidation method were used as Pickering stabilizers, and the 0.06 wt% CNCs-stabilized emulsions showed excellent storage stability and environmental stability. Soy protein isolate-curcumin complex (SPI-Cur) was prepared by the pH-driven method through hydrophobic interactions and hydrogen bonds, thus enhancing the water solubility of curcumin. SPI-Cur exhibited stronger binding affinity to MD than to PUL, enabling efficient encapsulation in the dispersed phase of MD/PUL Pickering emulsions. Furthermore, the emulsion system significantly enhanced the storage, photostability and thermal stability of SPI-Cur. The bioaccessibility of encapsulated SPI-Cur reached 51.98% after in vitro simulated digestion, which was significantly higher than that of free SPI-Cur (37.62%). This study provides an environment friendly strategy to address the poor water solubility and stability bottlenecks of curcumin in functional foods, and expands the application of W/W Pickering emulsions for encapsulating and delivering of hydrophilic bioactives.

Development and Stability Evaluation of Oleogel-in-Water Emulsions Using Whey Protein Isolate–Ferulic Acid Nanoparticles for Ganoderma Lucidum Spore Oil Encapsulation

This work evaluated how ferulic acid (FA) impacted the conformational properties of whey protein isolate (WPI) and altered the environmental tolerance of oleogel/water (Og/W) emulsions formulated with Ganoderma lucidum spore oil (GLSO). Molecular dynamics simulation analyses revealed that FA interacted with α-lactalbumin via hydrogen bonding and hydrophobic interactions, whereas it bound into the hydrophobic cavity of β-lactoglobulin through a “lock-and-key” mode driven primarily by hydrophobic forces. Fourier transform infrared spectroscopy analysis verified that such non-covalent forces triggered the dissociation and structural extension of WPI, which was manifested as a significant loss of α-helix and β-sheet architectures along with a corresponding rise in random coils. FA addition increased the positive charge, mean droplet size, interfacial contact angle and antioxidant stability of WPI-FA nanoparticles when the WPI-to-FA ratio exceeded 1:2 (i.e., WPI was in excess relative to FA). The GLSO-based Og/W emulsions exhibited a weak gel structure with predominantly elastic characteristics. Furthermore, WPI-FA nanoparticles fabricated at a 2:1 ratio minimized emulsion droplet size and imparted optimal stability to the Og/W emulsions, demonstrating superior freeze–thaw and salt resistance, alongside suppressed GLSO flavor release. This work provides critical insights into tailoring protein-polyphenol interactions to stabilize GLSO-based Og/W emulsion delivery systems for food applications.

DEVELOPMENT OF A POLYCOMPONENT FAT EMULSION AND STUDY OF ITS PHYSICOCHEMICAL PROPERTIES

This article focuses on the development of a polycomponent fat emulsion and the investigation of its physicochemical properties. The emulsion exhibited a moderately acidic pH of 5.64 ± 0.12, indicating suitability for food applications and consistent structural stability. The structured lipid matrix, formed by rice bran wax and stabilized with chickpea flour, maintained emulsion integrity during storage at 4 °C. Water activity (aw) was measured at 0.947, reflecting a relatively high level of free moisture typical of oil-in-water food emulsions, emphasizing the need for proper storage conditions to ensure microbiological stability. Rheological analysis revealed shear-thinning behavior, with apparent viscosity decreasing from 83.43 to 29.60 mPa·s as rotational speed increased, demonstrating progressive disruption of internal interactions under stress. Color and oil binding capacity measurements confirmed a visually uniform and stable system. Overall, the emulsion combines improved lipid composition with desirable technological properties and has potential as a structured fat system or partial animal fat replacer in various food products. Further studies will investigate the possibility of using this emulsion as a partial animal fat replacer in cooked sausage products.

Chitosan–cinnamaldehyde–whey protein concentrate stabilized W1/O/W2 double emulsion for co-encapsulation of tea polyphenols and β-carotene

Enhanced oxidative stability of O/W Pickering emulsions based on whey protein nanogels.

Lipid oxidation severely limits the stability of food emulsions. This study aimed to improve the interfacial protection of whey protein emulsions by developing nanogel WPI based O/W Pickering emulsion (GWE). Emulsions stabilised by non-heated WPI (NWE) and heat-treated WPI (HWE) were prepared for comparison. Results showed that GWE offered protection against metal induced lipid oxidation and during accelerated storage at 50 °C for 9 days, with significantly lowest amounts of hydroperoxides (1.30 mM) and MDA (8.8 μM). Headspace GC-MS analysis also confirmed that GWE produced less volatile oxidation products, with less aldehydes, ketones and furans after 9 days accelerated storage. Furthermore, GWE showed the lowest protein lipid co-oxidation products formation rate with midpoints of 4.2 days compared with 3.3 and 2.9 days for NWE and HWE, respectively. It demonstrates that GWE effectively modulates oxidation pathways and reduce protein-lipid co-oxidation in protein-based emulsions.

Co-delivery of bioactive compounds in W/O high internal phase emulsions: Stability, in vitro digestion, and cytotoxicity.

Water-in-oil high internal phase emulsions (W/O HIPEs) are emerging as promising vehicles for low-calorie formulations and incorporation of bioactives. This study evaluated W/O HIPEs to co-deliver β-carotene and catechins from green tea extract (GTE), focusing on stability, in vitro digestion (lipid hydrolysis and bioaccessibility), and cytotoxicity. W/O HIPEs remained macroscopically stable (no phase separation) for 60 days, although significant droplet coalescence was observed, more pronounced in catechin-loaded HIPEs stored at 23 °C. W/O HIPEs exhibited gel-like behavior, contributing to resistance under gastric conditions, with phase inversion occurring only during intestinal digestion, where 80-95% free fatty acids were released. Bioaccessibility of β-carotene improved from 37% (free form) to 65-73% after incorporation and reached 99% when co-delivered with catechins from GTE. Catechins´ bioaccessibility increased from 9% to 14-31%. In vitro digested W/O HIPEs showed no reduction in metabolic activity of differentiated co-cultures, supporting their potential applicability in functional foods.