Comparison of mesquite and arabic gum with three different starch derivatives for microencapsulation of lemon essential oil by spray-drying

Among the most relevant advances in new encapsulating materials are modified starch derivatives, which exhibit emulsifying capacity and form low-viscosity solutions, competing with the properties of arabic gum. Another promising alternative is the use of mesquite gum. For the rational application of encapsulating agents, it is essential to characterize their properties according to each specific use. In this study, three modified starches (N-Lok, Capsul, and National-46) were evaluated in comparison with arabic gum ( Acacia senegal ) and mesquite gum ( Prosopis spp ), with the aim of encapsulating lemon essential oil through spray drying. Three oil-to-encapsulant ratios (0.5, 0.6, and 0.7) were studied, determining the characteristics of the oil/water emulsions and the properties of the resulting microcapsules. The results showed that N-Lok starch, at a 0.5 ratio, produced the emulsion with the smallest droplet size, the highest encapsulation efficiency, and the lowest mean volumetric diameter of the microcapsules. In general, the starches yielded nearly spherical and defect-free microcapsules, except for those obtained with National-46. In contrast, the microcapsules produced with arabic gum and mesquite gum exhibited rough, dented surfaces. Regarding oil retention over time, the highest efficiency was observed with arabic gum, followed by N-Lok starch and mesquite gum.