SOLUBILITY OF CARNOSIC ACID IN SUPERCRITICAL CO_2 + ETHANOL AS A MODIFIER: MEASUREMENTS AND THERMODYNAMIC MODELLING

摘要

Antioxidants are widely used in food products to preserve deterioration of their lipid components. Lately the nutraceutical properties of such compounds have driven much attention for their relationship with human health, and then natural antioxidants are preferred. Among natural antioxidants, rosemary (rosmarinus officinalis L.) has been described as one of the spices with higher antioxidant activity, which has been mainly attributed to carnosic acid content [1]. The present study is devoted to the experimental measurement and thermodynamic modeling of solid carnosic acid solubility in supercritical CO_2 + ethanol as a co-solvent. Measurements were carried out at temperatures in the range of 313.15 K and 333.15 K, pressures ranging from 280 to 400 bar, and at different content of the modifier ethanol (from 0.7% to 10%). The Group Contribution Associating Equation of State (GCA-EoS) [2] was applied in this work to represent the experimental solubility data obtained.