Vapor-liquid distribution coefficients of hops extract in high pressure CO₂ and ethanol mixtures and data correlation with entropy-based solubility parameters

Vapor-liquid distribution coefficients (K) of hops extract in high pressure CO₂ and ethanol mixture solvents were measured with a flow apparatus at temperatures from 323 to 343 K, pressures from 8 to 10 MPa and feed concentrations of hops extract in ethanol solvent from 0.5 to 5 wt%. Distribution coefficients of β-myrcene, caryophyllene, humulene, cohumulone, humulone, colupulone and lupulone were found to be independent of feed concentration in ethanol solvent (from 0.5 to 5 wt%) for a given temperature and pressure. Thus, feed composition of hops extract was fixed at 0.5 wt% and both temperature and pressure effects were examined. Pressure dependence of the distribution coefficient could be clearly observed, while the temperature dependence of the distribution coefficients was relatively small. Data could be correlated with the entropy-based solubility parameter model to within 20% deviation in log K.