Spray drying of buriti oil-in-water emulsions as potential systems for the delivery of bioactive compounds

Abstract

Buriti, a native palm from the Amazonian rainforest, is a source of high-quality oil due to its high content of oleic acid and lipophilic antioxidant compounds such as β-carotene. To confer greater stability to these bioactive compounds, buriti oil O/W emulsions were prepared as delivery systems and dried by spray drying. O/W emulsions 10:90 (w/w) were prepared, and the response surface methodology (RSM) was applied using a central composite design with two factors, three levels, and five replicates at the center point to evaluate the effect of the soy protein isolate (SPI) (5, 10 and 15 % w/w) and drying temperature (140, 160 and 180 °C) on the optimization of the spray drying process. Different properties of the powders were evaluated as response variables, including process yield and encapsulation efficiency. Based on the adjusted quadratic models of response variables, the optimal conditions were determined: SPI 5.45 % w/w and drying temperature of 180 °C, with a low predictive error and a desirability of 0.884. Under these conditions, the results obtained were yields of 94.95±1.10 %, solubility 94.09±1.23 %, oil encapsulation efficiency 85.41±1.24 % and carotenoid encapsulation efficiency 44.34±1.89 %. Morphological analysis showed semi-spherical particles without agglomeration, with an average diameter of 3.38 ± 0.41 μm, and evidence of a true core-wall inclusion, as observed in the DSC and TGA analyses. The above makes buriti oil microcapsules an excellent alternative for food enrichment and their use in cosmetic and pharmaceutical industries.