Supercritical Carbon Dioxide Extraction of Marigold Lutein Fatty Acid Esters: Effects of Cosolvents and Saponification Conditions

Extraction of lutein fatty acid esters from marigold flower using supercritical carbon dioxide (SC-CO2) with cosolvent was investigated. Without the cosolvent, the total xanthophylls yield increased with increasing temperature and pressure of SC-CO2, and the optimal condition was found to be at 60°C and 40 MPa. At this condition, the highest total xanthophylls percent recovery was 74.4 ± 0.9%. Palm oil was found to be a more efficient cosolvent than soybean oil, olive oil, and ethanol, resulting in a 16% increase in the total xanthophylls recovery to 87.2 ± 4.4% when 10% (w/w) of palm oil was used. Furthermore, saponification of the oleoresin for 3 h at 75°C with 40% w/v KOH solution at the oleoresin to solution ratio of 1 g to 2 ml was found to suitably convert lutein fatty acid esters into free lutein.