The effects of different modifiers and processing conditions on the compositions, yield, and antioxidant
activity of carotenoid by supercritical CO2 (SC-CO2) extraction were studied. Increasing the percentage of
modifier would increase the yield, but no significant changes were observed on the antioxidant properties
of carotenoids extracted at 50 C with low concentration (5%) of single modifier. As single modifier,
the oil showed the pronounced effects on the yield and antioxidant activity of extracts compared to the
effects of water and ethanol. The combination of ethanol and water, or ethanol and oil, or water and oil in
SC-CO2 extraction showed that the yields of carotenoids were higher than for the single modifier with
equal amount. The modifier and operating temperature of SC-CO2 notably influenced the selectivity of
carotenoids, especially the ratio of cis-b-carotene/total carotenoids. The antioxidant activity didn’t show
a liner correlation with the total yield of carotenoids. The antioxidant activities of unit mass carotenoid
extract were decreased after adding modifiers at both 50 C and 80 C. At lower concentrations of water
(5% and 10%), the antioxidant activity of unit mass carotenoid extracts was higher at 50 C. The highest
antioxidant activity of unit mass carotenoid extract was found at 80 C with both single and combined
modifiers.