Integral Use of Chia Seeds in Microencapsulation Processes for the Development of Oil-Based Potential Functional Food...

An integral use approach of chia seeds was applied through microencapsulation, combining chia oil as the core with seed-derived proteins and mucilage as wall components for the development of potential functional food ingredients. Oil-in-water emulsions were formulated and dried by spray-drying and freeze-drying to evaluate how their distinct drying mechanisms influence the physicochemical, structural, and functional properties of chia oil microparticles. Both drying methods successfully produced chia oil microparticles, yielding powders with low moisture content, high encapsulation efficiency (approximately 91%, w/w), and high protein content. However, the drying method influenced the structural and functional properties of the microparticles. Scanning electron micrographs revealed lamellar structures in freeze-dried samples and spherical particles in spray-dried ones. After reconstitution, emulsion particle size increased during storage, particularly in freeze-dried systems, whereas spray-dried microparticles showed superior dispersibility and instant properties. Regarding oxidative stability, freeze-dried microparticles provided greater protection against lipid oxidation, reaching a peroxide value of 2.90 meq/kg oil after 45 days of storage. Besides, the α-linolenic acid content remained stable in freeze-dried microparticles, whereas a significant decrease was observed in spray-dried samples over the same period. A preliminary sensory evaluation of a beverage fortified with freeze-dried microparticles indicated that 94% of panelists were able to identify the fortified sample, which showed significantly lower sensory acceptance for taste, color, and appearance than the non-fortified product. Overall, these findings demonstrate the feasibility of using seed-derived proteins and mucilage as wall materials for chia oil encapsulation and highlight the potential of freeze-dried microparticles as ingredients for functional beverages.