Extraction of essential oils from aromatic herbs*

Thyme

NEOS vs. Hydro Distillation (HD)

*Solvent-free microwave extraction of essential oils from aromatic herbs: comparison with conventional hydro-distillation.
Journal of Chromatography A, 1043 (2004) 323-327.

Extraction of essential oils from orange peel**

** Solvent free microwave extraction of essential oils.
Chemistry Today, Vol. 26 n. 2 / March-April 2008.

Other Applications...

Microwave-Accelerated Dean Stark (MADS)

A recently published article “New and rapid analytical procedure for water determination: microwave accelerated Dean Stark”* describes for the first time how heating by microwave has been used as an energy source for rapid water determination with a Dean Stark apparatus.
The validation of this new procedure has been checked by applying it to water determination in olive fruits.
When using this new procedure fully reproducible results could be found in a substantially shorter time (less than 10 minutes compared to about 120 minutes with conventional method).
The efficiency of this new MADS technique is considerably higher than the conventional Dean Stark procedure if we take into account the short distillation times required, cost and energy used, and cleanliness of the process.
This MADS method could be appropriate for routine analysis of quality in the food, cosmetic, and pharmaceutical industry.

* “New and rapid analytical procedure for water determination: microwave accelerated Dean Stark”. Sébastien Veillet, Valérie Tomao, Franco Visinoni ,Farid Chemat. Analytica Chimica Acta 632 (2009) 203-207.

Microwave Steam Diffusion (MASD)

In a recent published article “Microwave accelerated steam distillation of essential oil from lavender: rapid, clean and environmentally friendly approach”*, the authors describe a new process design and operation for microwave accelerated steam distillation (MASD) of essential oils.
A packed bed of lavender flowers (Lavandula angustifolia Mill., Lamiaceae) sits above the steam source generated by microwave heating. Only steam passes through it without the boiling water mixing with vegetable raw material, as is the case in hydro-distillation. MASD has been compared with a conventional technique (steam distillation - SD), for the extraction of essential oil from lavender flower. Extraction of essential oils from lavender with MASD was better than SD in terms of energy saving, rapidity (10 min vs 90 min), product yield, cleanliness, and product quality.

* F. Chemat, M.E. Lucchesi, J. Smadja, L. Favretto, G. Colnaghi, F. Visinoni
Microwave accelerated steam distillation of essential oil from lavender: rapid, clean and environmentally friendly approach.
Analytica Chimica Acta, 2006, 555, 157-160.

Microwave Integrated Soxhlet (MIS)

A recently appeared article ”Microwave-integrated Soxhlet extraction of total fat in oils” * describes an improved process of Soxhlet extraction assisted by microwaves called Microwave-Integrated Soxhlet (MIS) for the extraction of oils and fats from different food matrices such as oleaginous seeds, meat, and bakery products.
After 32 minutes of MIS extraction it was possible to extract and concentrate the total amount of fat from foodstuff against the several hours required by conventional Soxhlet method which requires an additional step to concentrate fats and oils by evaporation of the solvent using a vacuum rotary evaporator.

* "Microwave-Integrated extraction of total fats and oils”.
Matthieu Virot, Valérie Tomao, Christian Ginies, Franco Visinoni, Farid Chemat.
Journal of Chromatography 1196-1197 (2008) 57-74.