Carotenoids such as eta-carotene are gaining interest in the food industry due to their nutritional and antioxidant proper-ties. Understanding the solubility behavior of carotenoids in supercritical CO2 (SC CO2) is fundamental for any industrial supercritical process application and design. Solubility of beta-carotene was measured in both a binary and a multicomponent complex system. Solubility of beta-carotene in the binary system was measured using a quartz crystal microbalance technique at temperatures of 40 and 50 degrees C and pressures ranging from 120 to 200 bar. Solubility of beta-carotene in the multicomponent complex system was determined from dynamic extraction experiments using a laboratory-scale supercritical extraction system. Carotenoids were extracted from freeze-dried carrots with SC CO2 at temperatures of 40 and 50 degrees C and pressures ranging from 120 to 327 bar. beta-Carotene solubility values for the binary system measured herein and reported in the literature are of the order of 10(-7) mole fraction while the solubility values for the multicomponent complex system (beta-carotene extracted from carrots with SC CO2) under the same conditions are 5-10 times smaller. Solubility in both systems increased with temperature and pressure. The difference in the solubility values obtained using both systems is mainly due to the matrix effects of the multicomponent complex system such as the cell structure and the interactions of beta-carotene with other components such as carbohydrates in the carrot matrix. (c) 2006 Elsevier B.V. All rights reserved.