The impact of different plant-based wall materials on the microencapsulation of Medium Chain Triglycerides (MCTs) via spray drying technique

There is a critical need in the market for sustainable, plant-based substitutes to replace conventional animal-derived wall materials for oil encapsulation. This study focused on the potential of a combination of plant-derived wall materials (pea protein isolate, soy protein isolate, modified starch and gum Arabic) and maltodextrin as a wall material for encapsulating medium-chain triglycerides (MCTs) oil using the spray drying technique. The physical characteristics of the spray-dried powders were evaluated including their microstructure morphology, particle size distribution, bulk density, tapped density, microencapsulation efficiency, water activity and moisture content. The emulsifying properties of plant-derived protein were found to be promising when compared to those of sodium caseinate, a commonly used control material in food formulations. The research on MCTs oil retention showed the wall materials to have the highest microencapsulation efficiency (MEE) with low surface oil content by sodium caseinate (90.85 ± 4.11 %) > soy protein isolate (86.14 ± 5.20 %) > modified starch (80.85 ± 4.13 %) > pea protein isolate (80.72 ± 8.32 %) > gum Arabic (75.21 ± 7.86 %). Observation through scanning electron microscopy indicated that the spray dried powders were predominantly spherical in shape with smooth, non-cracked surfaces, which suggests that the drying was effective and successfully retained the 40 % (w/w) MCTs oil within the microcapsules. The soy protein isolate and maltodextrin wall material microcapsules had the highest particle size and a mean diameter of (50.84 ± 5.47 µm). The successful production of these microcapsules demonstrates that the selected plant-derived matrix represents a viable and sustainable alternative to animal-based encapsulating agents in the development of functional lipid-based powder ingredients.