New Developments in the Field of High‐Pressure Extraction of Natural Products with Dense Gases (Invited Lecture)

Abstract

Abstract A short historical review is followed by a survey of more recent work, some of it still unpublished. Solubility determinations in the pressure range up to 3000 bar and at temperatures up to 80°C yielded new surprising results for the substance classes of the triglycerides, wax esters and sterols. The difficult problem of the high pressure extraction of flexible viscous masses, such as crude lecithin and similar pastes and slimes, could be elegantly solved by the continuous high pressure jet procedure. In the field of separation of substances of high vapour pressure, e.g. essential oils, new paths were opened up. We succeeded in separating selectively undesirable fatty oils, waxes and colouring matter. The procedure for the continuous deterpenation for the recovery of high quality concentrated flavours is also new. We could further show the possibility of removing lipophilic pesticides from plant material, e.g. DDT, γ‐HCH from sennae leaves and ‐pods.