Scientific papers on the NEOS Technology
Microwave-assisted Water Extraction of Green Tea Polyphenols
Ezzohra Nkhili, Valerie Tomao, Hakima El Hajji, Es-Seddik El Boustani, Farid Chemat and Olivier Danglesb*
Introduction – Green tea, a popular drink with beneficial health properties, is a rich source of specific flavanols (polyphenols). There is a special interest in the water extraction of green tea polyphenols since the composition of the corresponding extracts is expected to reflect the one of green tea infusions consumed worldwide.
Objective – To develop a microwave-assisted water extraction (MWE) of green tea polyphenols.
Methodology – MWE of green tea polyphenols has been investigated as an alternative to water extraction under conventional heating (CWE). The experimental conditions were selected after consideration of both temperature and extraction time. The efficiency and selectivity of the process were determined in terms of extraction time, total phenolic content, chemical composition (HPLC-MS analysis) and antioxidant activity of the extracts.
Published online in Wiley Interscience: 16 July 2009
Microwave accelerated steam distillation of essential oil from lavender: A rapid, clean and environmentally friendly approach
F. Chemat, M.E. Lucchesi, J. Smadja, L. Favretto, G. Colnaghi, F. Visinoni
A new process design and operation for microwave accelerated steam distillation (MASD) of essential oils was developed. 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 flowers. Extraction of essential oils from lavender with MASD was better than SD in terms of energy saving, rapidity (10 min versus 90 min), product yield, cleanliness and product quality.
© 2005 Elsevier B.V. All rights reserved.
Additonal Papers on Open Vessel Microwave Extraction
A new process for extraction of essential oil from Citrus peels: Microwave hydrodiffusion and gravity. N. Bousbia, M.Vian, M. Ferhat, B. Meklati, F.Chemat; Journal of Food Engineering, 2009, 409-413.
Microwave hydrodiffusion and gravity, a new technique for extraction of essential oils. M.Vian., X.Fernandez, F. Visinoni, F. Chemat; J. Chromatogr.A, 2008, 1190, 14-17.
Solvent free microwave extraction of Elletaria cardamomum L.: A multivariate study of a new technique for the extraction of essential oil. M.. Lucchesi, J. Smadj, S. Bradshaw, Louw, . Chemat; Journal of Food Engineering, 2007, 79, 1079-1086.
An improved microwave Clevenger apparatus for distillation of essential oils from orange peel. M. Ferhat, B. Meklati, J. Smadja, F. Chemat; J. Chromatogr. A, 2006, 1112, 121-126.
Microwave accelerated steam distillation of essential oil from lavender: A rapid, clean and environmentally friendly approach. F. Chemat, M. Lucchesi, J. Smadja, L. Favretto, G. Colnaghi, F. Visinoni;Analytica Chimica Acta, 2006, 555, 157-160.
Solvent-free microwave extraction of essential oil from aromatic herbs: comparison with conventional hydro-distillation. M. Lucchesi, F. Chemat, J. Smadja; J. Chromatogr. A, 2004, 1043, 323-327.