Optimization of the spray drying process for developing cupuassu powder.

A central composite design was used to optimize the spray drying process for developing cupuassu () powder. The influence of inlet air temperature (T) (120-180 °C), feeding rate (F) (3-12 mL/min) and maltodextrin concentration (C) (10-40%) on the properties of moisture, water activity (a), hygroscopicity, water solubility index (WSI), ascorbic acid (AA) and total phenolic compounds (TPC) were analyzed using response surface methodology and desirability function. In addition, powder morphology was assessed using scanning electron microscopy. The T and F parameters significantly influenced the moisture and a, while the other responses (hygroscopicity, WSI, AA and TPC) were influenced by the T and C parameters. The highest C and intermediate T and F levels showed the best morphological characteristics (particles integrity, spheres shapes and smooth surfaces). The desirability function defined the optimal process conditions as T = 150 °C, F = 7.5 mL/min and C = 40%.