Optimization of Parameters for Obtaining Microparticles Containing Açai Extract (Euterpe precatoria Mart.) by Spray Drying

Açai (Euterpe precatoria Mart.) is a fruit with tremendous bioactive potential, but its high perishability necessitates the use of technologies to improve its stability and further enhance its bioactivity, such as microencapsulation by spray drying. Maltodextrin (MD) and gum Arabic (GA) are commonly used encapsulants in spray drying, but their combination for the microencapsulation of açai extract has not been studied. This study aimed to optimize the microencapsulation of açai extract using spray drying, evaluating its effect on the physicochemical and functional properties of the microparticles (MPs). Optimization was performed using response surface methodology with a central composite rotatable design, considering inlet air temperature (IAT) and polymer ratio (GA:MD) as factors. The optimal conditions were 135 °C IAT and a 50:50 GA:MD, under which a process yield of 76.05%, total phenolic compounds of 2791.83 mg GAE/100 g, and hygroscopicity (HYG) of 7.28% were obtained. Solubility (WSI) and total anthocyanin content (TAC) were not optimized due to lack of fit (p < 0.05). The experimental validation showed precise agreement between predicted and experimental values, with relative errors of less than 5%. The MPs presented spherical forms with rough surfaces. The effectiveness of the microencapsulation process demonstrates the potential of açai MPs as possible functional ingredients for future food applications.