In recent years, the application of nanoencapsulation has attracted enormous attention for various food and pharmaceutical purposes. In this study, a functional powder containing limonene (the nutraceutical at concentration of 5 and 10 %) was prepared using octenyl succinic anhydride-modified starch (OSA-ST) and maltodextrin as carriers at 15 and 30 %. The emulsions were sonicated at a frequency of 30 kHz and a power of 100 W for 9 and 18 min, and the final nanoparticles were prepared through freeze-drying. The particle sizes were in the ranges of 62–248 and 10–24 nm in the suspensions of OSA and maltodextrin, respectively. The smaller particles of the maltodextrin-prepared sample resulted in more transparency. The zeta potential and consequently the stability of the maltodextrin-prepared emulsions were higher than those of the OSA-ST-prepared ones. As the maltodextrin concentration increased, this parameter was elevated from −42 to −36 as a result of the coverage of the surface-active lipids. The results of solubility correlated with those of the zeta potential (89.21 % for maltodextrin-prepared and 82.51 % for OSA-ST-prepared samples). The highest encapsulation efficiency (EE = 0.9) belonged to the samples prepared with OSA-ST. Comparison of the scanning electron microscopy (SEM) images revealed that the type of the wall material influenced the physical structure of the nanoparticles which were mostly porous and flake-like. Considering its encapsulating-emulsifying properties, OSA-ST can be suggested as a carrier for limonene with the need for emulsifiers.
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