SUPERCRITICAL CO2 EXTRACTION OF ANNATTO (BIXA ORELLANA) PIGMENTS AND SOME CHARACTERISTICS OF THE COLOR EXTRACTS

Supercritical CO2 (SC-CO2) was used to extract natural food colors from Annatto (Bixa orellana) seeds with different pressures and temperatures. Results from the reverse thin-layer chromatographic separation and GC/MS revealed that SC-CO2 extracts were composed mainly of bixin, geranylgeraniol and norbixin. Differences in absolute values of solubility parameters (SPD) between these main compounds and SC-CO2 indicated bixin was more easily extracted than norbixin under conditions used. A higher yield of total pigments was obtained at extraction pressure above 310 bar than at 210 bar and 50°C.