This work aims to study supercritical anti-solvent (SAS) micronization of lutein derived from marigold
flowers. Lutein solution in dichloromethane (DCM) or ethanol was atomized into the stream of supercritical
carbon dioxide (SC-CO2) through a concentric nozzle in a pressurized vessel. The effects of pressure
and SC-CO2 flow rate on morphology, mean particle size (MPS) and particle size distribution (PSD) were
investigated. The reduction in lutein MPS from 202.3 m of unprocessed lutein to 1.58 m and 902 nm
could be achieved by SAS micronization using DCM and ethanol, respectively. In both solvent systems,
no significant effects of pressure and SC-CO2 flow rate on particle morphology were observed. However,
pressure was found to have a significant effect on MPS and PSDs of lutein particles.