SIMULTANEOUS DISTILLATION EXTRACTION UNDER STATIC VACUUM - ISOLATION OF VOLATILE COMPOUNDS AT ROOM-TEMPERATURE

The simultaneous distillation-extraction (SDE) system developed by Likens and Nickerson (ASBC Proceedings, 1964, p. 5) and modified by Godefroot, Sandra and Verzele [J. Chromatogr., 203 (1981) 325] is one of the most popular methods currently used to isolate volatile components from a matrix prior to gas chromatographic analysis. Since it leads to a thermal generation of artefacts, the device has been improved in the present work to allow isolation between 20 and 40-degrees-C under vacuum. The system was closed and made airtight by means of a valve under static vacuum to avoid volatile losses. These conditions require the use of solvents with a boiling point close to that of water and the temperature must be electronically regulated. The absence of artefact generation was tested with linalyl acetate, honey and a Maillard model reaction. The recovery yields of classical SDE and SDE under vacuum were found to be similar.