Application of Chrastil's model to the extraction in SC-CO2 of β-carotene and lutein in Mentha spicata L.

Extraction of β-carotene and lutein in Mentha spicata L. using supercritical carbon dioxide (SC-CO2) was studied. Among these carotenoids, all-trans-β-carotene, all-trans-lutein and a cis-isomer of lutein exhibited an increase in the extracted amount at CO2 densities values >550–600 g/l, whereas the cis-isomer of β-carotene did not follow this pattern. A temperature increase resulted in higher extraction yields for the studied carotenoids. Chrastil's equation was used to describe the solubility behavior being in good agreement with experimental values. From the results of this study, it could be stated that simple Chrastil's model may be applied to select appropriate operating conditions of the extraction process for trans-β-carotene, trans-lutein and cis-lutein occurring in M. spicata L.