SUPERCRITICAL CARBON-DIOXIDE EXTRACTION OF CARAWAY ESSENTIAL OIL

Caraway seeds were extracted with liquid and supercritical carbon diox ide at 23-40-degrees-C and 90-100 bar. The extracts were analyzed for carvone and limonene, and compared with essential oil obtained by stea m distillation. Slight fractionation was observed during the extractio n. The effect of process parameters, such as temperature, pressure, an d solvent flow rate and direction, on essential oil recovery was descr ibed using a simple model with mass transfer between a liquid mixture of essential and fatty oils and the solvent, and with diffusion resist ances both in the liquid mixture and in the walls of caraway cells.