Enhancing composite emulsion stability through electrostatic modulation of polysaccharides-whey protein isolate interactions for probiotic encapsulation.
Aug 2026· Food Chemistry· Vol 525 Pt 4, pp.
150681
· 0 citations· 42 references
Medicine
Abstract
This study investigates how electrostatic interactions between whey protein isolate (WPI) and polysaccharides (konjac glucomannan, guar gum, pectin, sodium alginate, chitosan) affect the stability and encapsulation of high-internal-phase emulsions (HIPEs, oil fraction >74%), revealing charge-driven structural and network stabilization mechanisms. The findings demonstrate that anionic WPI (pH 7.0) alone was more effective than cationic WPI (pH 4.0) in stabilizing oil-in-water HIPEs. Neutral polysaccharides enhanced emulsifying performance through viscosity-induced stabilization. While electrostatic repulsion increased ζ-potential of the complexes, thereby synergistically strengthening hydrophobic interaction-driven emulsifying activity. In contrast, excessive attraction (pectin, ζ-potential -17.0 mV) destabilized structural network through bridging or depletion flocculation, whereas moderate attraction (sodium alginate, ζ-potential -11.5 mV), facilitated the formation of stable emulsion systems. Notably, sodium alginate-WPI systems demonstrated robust stability (for 4 months) across all electrostatic conditions and offered excellent biocompatibility (<5%) and probiotic protection (>9.05 log CFU/mL). Collectively, these findings elucidate the mechanism of electrostatic tuning in stabilization of HIPEs, providing a promising approach for probiotics delivery.
The application of gelatin in low-oil emulsions is frequently limited by poor stability. In this study, gelatin-based complexes were respectively constructed with sodium alginate (SA), hyaluronic acid (HA), or Tremella fuciformis polysaccharide (TP), three anionic polysaccharides with distinct molecular architectures. The effects of polysaccharide type and concentration (0.1%, 0.2%, 0.3%, w/v) on the physicochemical characteristics of the complexes and their emulsifying performance were systematically investigated. Non-covalent interactions including electrostatic attraction and hydrogen bonding induced structural unfolding of gelatin, significantly increasing surface hydrophobicity and three-phase contact angle. Notably, the polysaccharide concentration of 0.2% was identified as an optimal balance point. SA exerted the strongest electrostatic contraction, inducing the formation of compact nanospheres. In contrast, HA exhibited steric-dominated aggregation, whereas TP formed branched-structure-mediated spherical assemblies stabilized by a hydrated surface layer and structural reinforcement. Furthermore, emulsions stabilized by gelatin-polysaccharide complexes exhibited more uniform droplet size distributions and markedly enhanced stability. These findings provid a potential strategy for overcoming the instability of low-oil emulsions and may facilitate the development of more stable and healthier instant soup products.
Xinyu Kou, Jinxuan Cao, Jinpeng Wang et al.· Food Chemistry· 0 citations
Soy protein isolate (SPI)–polysaccharide-stabilized high internal phase emulsions (HIPEs) are promising fat alternatives for meat analogs. However, the distinct contributions of polysaccharide charge and viscosity to emulsion formation, stabilization and meat analog quality remain unclear. This study systematically investigated five polysaccharides with different charges and viscosities, namely cationic chitosan (CS), neutral locust bean gum (LBG) and guar gum (GG), and anionic xanthan gum (XG) and high methoxyl pectin (HP), in modulating SPI structure, HIPE performance, and plant-based patty quality. Results showed that polysaccharide charge dominated SPI-polysaccharide interactions and dictated SPI conformational remodeling. Neutral polysaccharides interacted with SPI through hydrogen bonding/hydrophobic interactions, significantly increasing the β-sheet content (GG: from 35.91% to 43.23%), and achieving the smallest initial droplet size through a high interfacial adsorption rate (GG: 6.81 μm). During emulsion stabilization and flavor retention, viscosity was the predominant factor. High-viscosity XG and GG excelled in inhibiting droplet aggregation, reducing gravitational separation, and maximizing volatile flavor retention under both heating and storage. At the application stage, viscosity predominantly influenced the hardness of patties. This study reveals the division of labor between polysaccharide charge and viscosity across different performance dimensions of HIPEs, guiding polysaccharide selection for tailoring HIPEs in meat analogs.
Ying Chen, Jiamei Yu, Lin Zhang et al.· Current Research in Food Sci...· 0 citations
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.
Wenjia Yan, Yuting Bao, Hao Wang et al.· Gels· 0 citations
Hydrophobic bioactive compounds are difficult to deliver because of poor water solubility, limited stability, and uncontrolled release. In this study, chitosan-soy protein isolate (CS-SPI) conjugates were prepared by dry-heat Maillard reaction and used as natural polymeric emulsifiers for curcumin-loaded emulsions. The highest grafting degree of 15.3% was obtained at 70 °C, 74.50% relative humidity, 96 h, and a CS:SPI mass ratio of 1:3. Compared with chitosan and CS-SPI non-covalent complex-stabilized emulsions, the CS-SPI conjugate-stabilized emulsion showed the smallest droplets (7.23 μιη) and a more uniform distribution. It maintained high encapsulation efficiency after 6 days of storage (94.28%) and suppressed burst release during simulated gastric digestion, extending curcumin release to about 72 h. These results suggest that CS-SPI conjugates improve emulsion stability and sustained-release performance.
Myofibrillar protein (MP) gels with desirable textural properties are highly favored by customers. In the present study, the effects of different charged polysaccharides, including neutral dextran (DX), anionic κ-carrageenan (KC) and cationic chitosan (CS), on modulating the thermal gelation properties of microbial transglutaminase (MTGase)-mediated MP were investigated. The results suggested that the thermal gelation characteristics of composite gel systems formed by combining MTGase with three polysaccharides respectively were improved, regardless of polysaccharide ion types. Furthermore, cationic CS was the most effective in increasing water-holding capacity (WHC), texture properties, and viscoelastic characteristics of composite gels, followed by neutral DX and then anionic KC. Based on the results of water state and distribution, the incorporation of three polysaccharides strengthened the water entrapment effect of MTGase-mediated MP gel network. Additionally, cationic CS displayed the greatest effect on driving the generation of β-sheet structures, facilitating the formation of disulfide bonds and enhancing hydrophobic interactions, thereby contributing to the formation of a uniform and well-organized gel matrix network. These findings provide theoretical support for formula optimization and quality improvement of meat products by modulating MP during thermal processing.
Xiaomin Zhang, Shuxia Wu, Cheng Tang et al.· International Journal of Bio...· 0 citations
Polysaccharides offer biodegradable and sustainable means of stabilizing emulsions. However, to be effective they often need surface modification or addition of surfactants, compromising their overall environmental and economic viability. We present an alternative approach by leveraging the solubility window of polysaccharides in alkaline or acidic environments. By modulating pH, polysaccharides are dissolved and subsequently partially precipitated, yielding a controlled coexistence of soluble chains and precipitated particles, quantified via mass-based solubility measurements. Emulsification at a partially precipitated stage produces emulsions with enhanced microstructure compared to "As-received" polysaccharides at neutral pH. Subsequent in situ pH neutralization further confines polysaccharide precipitation within the narrow aqueous channels between droplets, forming a mechanically stable particle-particle and particle-droplet network, as evidenced by enhanced viscoelastic moduli and reduced droplet coalescence. Using enzymatically polymerized α-1,3-glucan and β-1,4-chitosan from aquaculture, we demonstrate the versatility of this method, providing a practical approach for polysaccharide-based emulsion engineering.
Karim Firdous, M. Aghajamali, S. A. Rasaki et al.· Nanoscale· 0 citations