Desalination of mussel cooking juices by electrodialysis: effect on the aroma profile

The production of aromatic concentrates from seafood cooking juices can be done by reverse osmosis. Nevertheless, the high osmotic pressure of these juices makes necessary a preliminary step of desatination by electrodialysis. The aim of this work was to evaluate the impact of electrodialysis has on the aromatic quality of a mussel cooking juice. This evaluation was done by sensory analysis and by gas chromatography coupled with mass spectrometry or with olfactometry. Results show that the salt concentration can be decreased from 20 gl(-1) to 2.8 gl(-1) without aromatic profile modification. Under this critical salt concentration, a significant modification of the sensory and chromatographic profiles was observed. This critical salt concentration was obtained when the current density reached its limiting value. It's well known that at this value, solutions located near the membrane surface undergo physico-chemical changes (water-splitting, pH change...). (c) 2004 Elsevier Ltd. All rights reserved.