Supercritical CO2 and subcritical propane extraction of spice red pepper oil with special regard to carotenoid and tocopherol content

A study is conducted to optimize the supercritical fluid extraction of spice paprika oil (oleoresin) using supercritical (SF) CO2 and subcritical propane as the solvents. The main focus is on carotenoid and tocopherol composition as the quality attributes of technological and nutritional interest. The maximum oil yield is 7.2 and 8.8 g per 100 g paprika with SF-CO2 and subcritical propane, respectively. For the implementation of complete extraction at the given conditions, the ratio of solvent to solid is found to be 6.0 and 1.0 using SF-CO2 and propane, respectively. The carotenoids, particularly fatty acid esters of red xanthophylls, are hardly solubilized by SF-CO2, whereas with subcritical propane, 80-94% of such components could be mildly extracted. Tocopherols were easy to extract using either fluid, with propane being the most efficient solvent. The result of the impact of extraction conditions on the major carotenoids (such as capsanthin monoester, β-carotene, capsorubin diesters, and capsanthin diesters, as well as α-, β- and γ-tocopherol) are tabulated with special focus on the degree of loss during extraction by the two solvents.