Influence of solvent, matrix dielectric properties, and applied power on the liquid-phase microwave-assisted processes (MAP™) extraction of ginger (Zingiber officinale)

The present work reports on an assessment of the relative importance of the nature of solvent and the applied power on the liquid-phase microwave-assisted processes (MAP) extraction of ginger (Zingiber officinale). The dielectric properties of the matrix was also modified in a controlled fashion by the addition of strongly absorbing substances that do not alter the quality of the extract and that do not involve supplementary steps for the recovery of the extract while allowing greater yield in much reduced extraction times when compared to conventional Soxhlet procedures. These results show the potential value of controlling the energy density of the system and the possibility of using a benign chemical such as water as a "lens" to enhance microwave-assisted processes such as the extraction of natural products from plant material., Crown Copyright (C) 2002 Published by Elsevier Science Ltd. All rights reserved.