Controlling the functional performance of emulsion-based delivery systems using multi-component biopolymer coatings

Area of Science:

• Food science and technology
• Materials science
• Biochemistry

Background:

• Emulsion-based delivery systems are crucial for encapsulating bioactive lipophilic components.
• Controlling the digestion and release of these components requires tailored surface properties of lipid droplets.
• Biopolymer coatings offer a promising strategy for modifying droplet behavior.

Purpose of the Study:

• To engineer multi-component biopolymer coatings on lipid droplets using interfacial electrostatic deposition.
• To investigate the pH-dependent stability of these coated droplets.
• To evaluate the impact of biopolymer coatings on in vitro lipid digestion.

Main Methods:

• Formation of multi-component coatings: beta-lactoglobulin (protein), chitosan (cationic polysaccharide), and pectin or alginate (anionic polysaccharide).
• Interfacial electrostatic deposition technique for coating assembly.
• pH-stability assessment of coated droplets across a range of pH values.
• In vitro lipid digestion model (pH-stat) to measure digestibility.

Main Results:

• Protein-chitosan coated droplets showed instability at pH > 6 without an outer layer.
• Addition of pectin or alginate outer layers provided stability from pH 7 to 4, with aggregation at lower pH.
• Polysaccharide coatings significantly reduced the rate of in vitro lipid digestion.

Conclusions:

• Multi-component biopolymer coatings, particularly with an outer anionic polysaccharide layer, enhance the stability of emulsion droplets over a defined pH range.
• These coatings effectively modulate lipid digestion rates, offering control over bioactive component release.
• The findings are significant for designing advanced delivery systems in the pharmaceutical, biopharmaceutical, and food industries.