Quantitative analysis of key spray drying variables’ impact on maltodextrin powder parameters

This study investigates the influence of feed and process parameters on the morphology and properties of maltodextrin powders produced by co-current spray drying in a semi-industrial dryer. The effects of feed concentration (30–50 wt.%), feed temperature (30–90 °C), drying air temperature (170–200 °C), and feed flow rate (8–12 kg/h) were systematically evaluated. Powder characteristics including particle size distribution (PSD), moisture content, density, flowability, and morphology were analyzed, supported by Pearson correlation mapping. Results showed that drying air temperature had the strongest overall impact, narrowing PSD, decreasing mean particle size (from ∼140 to ∼30 µm), and improving flowability (Carr index from >25% to <15%). Feed preheating reduced viscosity and surface tension, enhancing atomization and lowering moisture content. Higher maltodextrin concentration increased particle size and moisture but improved flowability, while higher feed flow rate produced finer powders of reduced flowability. Scanning electron microscopy images confirmed these trends, revealing transitions from irregular collapsed particles to spherical hollow morphologies. Overall, the study provides quantitative guidelines for optimizing spray drying of maltodextrin, with implications for improving powder quality while balancing process efficiency.