Supercritical fluid extraction: Application in the food industry

Abstract

Supercritical fluid extraction is an extraction process realized with supercritical fluids, which are at a temperature and pressure above their critical temperature and critical pressure. This process has shown to be very efficient one for the isolation of different substances of medium molecular weights and molecules of relatively low polarity. The solubility of more polar substances in supercritical fluids can be improved by the addition of small amounts of other polar solvents (cosolvent) to the supercritical fluids, which is the main solvent in extraction process. The advantage of supercritical extraction compared to other extraction procedures (the application of classical organic solvents hydrodistillation, distillation with steam) is that SFE is usually performed at moderate temperature (e.g. with SF CO2 at 40-70?C) so it can be applied for the separation of different substances which are thermally unstable and have a larger vapour pressure. All of these facts indicate that SFE is of special interest for the food and pharmaceutical industry.