Soy Protein Isolate-Sodium Alginate Composite Particles for Stabilization of High Internal Phase Pickering Emulsions:...

Area of Science:

• Food Science
• Colloid and Surface Science
• Materials Science

Background:

• High internal phase Pickering emulsions (HIPEs) are of interest as stable fat replacements.
• Biopolymer-based particles offer potential for stabilizing HIPEs.

Purpose of the Study:

• To develop and characterize soy protein isolate (SPI) and sodium alginate (SA) composite particles for stabilizing HIPEs.
• To evaluate the interfacial properties and stability of SPI-SA stabilized HIPEs.

Main Methods:

• Composite colloidal particles of SPI and SA were prepared.
• Particle size, surface hydrophobicity, and wettability were analyzed.
• Interfacial protein adsorption, bound water content (low-field NMR), and interfacial layer structure (CLSM) were quantified.
• HIPEs stability was tested against heat, freeze-thaw, ionic strength, and storage.

Main Results:

• Optimal SPI-SA formulation (1.0% SA) yielded uniform particles with enhanced wettability (contact angle 80.8°).
• Maximal interfacial protein adsorption (83.7%) and increased bound water (T22 from 21.893 to 30.031 a.u.) were observed.
• HIPEs demonstrated excellent stability under various stress conditions, including heat, freeze-thaw, and high salt concentrations.

Conclusions:

• SPI-SA composite particles are effective natural stabilizers for robust HIPEs.
• These HIPEs exhibit significant potential for use in functional food applications as fat replacers.