Although steam distillation is the most well-known technique for extracting essential oil from plants, there are several other methods that are used to remove and concentrate the aromatic constituents from plant materials. Here is a brief description of each method and their influence on the aromatherapeutic properties and fragrance of the oil. The attached file may provide you further details:-

Dear Vinesh

I am listing some of the methods I know. I would also like to know the latest or recent techniques:

1. Clevenger hydro-distillation (laboratory technique with limited biomass and water and with cohobation. The oil is separated directly from the Clevenger apparatus or extracted with solvents like diethyl ether)

2. Microwave assisted hydro-distillation

3. Likens and Nickerson apparatus or simultaneous distillation and solvent extraction

4. Ultrasonic assisted solvent extraction

5.  Sub or super critical fluid extraction (CO2 or other gases used as solvents under pressure at specified temperature)

6. Hydro-distillation (field-level with large biomass and large body of water)

7. Hydro-cum-steam distillation or field distillation with or without cohobation

8. Steam distillation with or without cohobation

9. Hydro-diffusion

10. Solvent extraction (useful for extraction of concretes and absolutes from flowers and oleoresins from spices)

S. nos. 5-9 field-level extractions. Others mostly laboratory isolations with small biomass samples.

Designs (capacity, shape, material i.e. mild steel, stainless steel etc. )of field distillation units can be modified to suit the requirements of a farmer or an industry. Steam distillation can incorporate facilities for super-heated or saturated steam.

Both fresh and dried biomass or biomass chopped into small pieces or paste of biomass can be used.

Different types of solvents were used for isolating the oil from Clevenger and Likens and Nickerson apparatus.

Good luck.

For lab Clevenger method. Rest is described in detail by Dr. B.R. Rajeswara Rao.

Dear Prof. Vinesh

Read the attached abstract, may be it is useful to you.

Best wishes

The most scientific term that used to get essential oils from plants wherever the essential oils found (stem, root, leaves, buds, oil gland, .....) is extraction. There are many different methods of essential oils extraction from plants; steam distillation, water/hydro distillation, water-steam distillation, solvent extraction (concrete), extraction with wax (hot wax, cold wax), cold press (like citrus oils), SFE (super critical fluid extraction). these methods are used to get essential oils from plants and called "extraction".

Dear Prof. Abdelaleem

Is it extraction or isolation of essential oil from aromatic biomass (irrespective of the method and plant part and whether it is fresh or dry material)? You may see the response to a question I raised on the subject. Other researchers appear to differ from your observation. Any suggestions?

Good luck.

Pomades were made before the advent of solvent extraction from flowers like jasmine and tuberose by extracting them with fats/oils (enfleurage). In addition to expression or cold extraction of citrus peels, the essential oil is also obtained as a by-product of the fruit juice industry where centrifugation, osmosis/reverse osmosis, membranes etc. techniques are being used to purify the juices. In the refining of edible oils, certain volatile, aromatic compounds are removed as they are considered as impurities.

• Distillation for extraction of oil
• Microwave-assisted extraction
• Solid phase extraction
• Ultrasonic extraction
• Supercritical fluid extraction

http://www.ijeat.org/attachments/File/v3i6/F3302083614.pdf

Dear Brother

You can extraction EO s by Clevenger hydro-distillation in simple way.

Other thing is depend your lab facility. High techniques also available if you can feel easy.

Scientist BR Rao Sb. suggested so many  techniques.

It is also depend your plant materials,

To extract the essential oils, there are some traditional methods among them I can mention classical hydrodistillation using a standard Clevenger apparatus, turbohydrodistillation, steam distillation,…. you can find the definition of an essential oil as given by European pharmacopeia. However, in recent decades there is a growing interest in use of more advanced and environmentally techniques particularly those based upon the safe application of microwave beams, namely as microwave assisted extraction, solvent free microwave extraction. A complete list of these techniques is found in the famous booh of Prof. Chemat et al. entitled:

Chemat, F., Cravotto, G. (2013) Microwave-Assisted Extraction for Bioactive Compounds, Theory and Practice, Springer, New York.

I highly recommend reading this book to you to have a deeper insight into this topic.

The last point here is consideration of the difference between essential oils and volatile fractions isolated from plant organs when using the techniques bade upon solid phase micro extraction (SPME),…

I think the most easy way to do it would be hydrodistillation using a Clevenger apparatus. There are other techniques like supercritical extraction using carbondioxide which is used extensively now-a-days.

It is simple you can use

hydrodistillation or steam distillation using clevenger type apparatus or some modern technique such as microvave assisted distillation. this method you can apply just for research purposes

For high resolutive separation you should use a molecular distillation process

Dear Dr. Julien

Can you please provide more information on molecular distillation and any published papers with reference to aromatic plants and essential oil isolation using this technique.

Best wishes

Rajeswara Rao

Dear Dr Julien Sb

Please send me a research article on molecular distillation in MAPs also more information.

Although steam distillation is the most well-known technique for extracting essential oil from plants, there are several other methods that are used to remove and concentrate the aromatic constituents from plant materials. Here is a brief description of each method and their influence on the aromatherapeutic properties and fragrance of the oil. The attached file may provide you further details:-

My Dear Vinesh Kumar; Traditional Soxhlet method of distillation may be used commonly. Yes here are few links which will also help you in your research. Regards

http://link.springer.com/article/10.1007/s00216-004-2671-5

http://www.sciencedirect.com/science/article/pii/S0308814606003256

http://www.sciencedirect.com/science/article/pii/S0731708599001521

http://www.sciencedirect.com/science/article/pii/S0021967304008672

Plant material (50g)  was subjected to hydro-distillation for 5-6 hours, using a modified Clevenger-type apparatus to produce essential oil. The oil was dried by anhydrous sodiumsulphate (Na2SO4) and kept sealed in dark glass vial at -8 °C until use.Diluted essential oil (1/50 in n-heptane, v/v) was used for GC-MS analyses according to Milovanović et al. (2009). In order for a compound to be analyzed by GC/MS it must be sufficiently volatile.

Reference

Milovanović, I.L.J.; Mišan, A.Č.; Sakač, M.B.; Čabarkapa, I.S.; Šarić, B.M.; Matić, J.J. and Jovanov, P.T. (2009) : Evaluation of a GCMSmethod for the analysis of Oregano essential oil composition Food Processing. Quality and Safety, 3(4): 75-79.

Dear Prof. Vinesh

Please check these latest publications whether these are new methods or established ones.

Good luck.

Dear Vinesh

Check these 2 interesting publications:

1. Free and Glycosidically Bound Volatiles in Curry Leaves (Murraya koenigii) (L) Spreng authored by K. P. Padmakumari published in Journal of Essential Oil Research, 20:6, 479-481, DOI: 10.1080/10412905.2008.9700063.

I am adding the abstract of this paper:

Free and glycosidically bound aroma compounds from Murraya koenigii (L.) Spreng, were isolated and separated by Amberlite XAD-2 column. The fraction containing the free aroma compounds was eluted with pentane: diethyl ether (1:1). Aroma compounds from the bound fraction were released by β-glucosidase hydrolysis. Samples were analyzed by GC and GC/MS. Sixty-seven constituents were found to be present in the bound fraction where linalool was found to be the main constituent. In the free aroma fraction, seventy-eight constituents were present with octyl acetate being found as the main constituent. In the hydrodistilled oil, fifty-six compounds were identified and β-caryophyllene was the main compound.

2. Shankaranarayana, K.H. and Kamala, B.S. 1989. Six new essential oils from waste plant material. Indian Perfum. 33: 40-43.

I do not have the abstract. As far as I remember the authors re-distilled previously distilled aromatic biomass of a plant in Clevenger by adding an acid to the water in the Clevenger and got 6 different kinds of essential oils with different compositions. If you can get a copy of the paper it will be good reading.

Best wishes.

Dear Vinesh

In response to my query (see the thread) Dr. Sergei Esipov posted this link to a publication on solar power distillation unit for producing essential oils from aromatic plants.

http://www.solarfood.org/solarfood2009/3_Full_papers/Technologies/62_AnjumMunir.pdf

https://www.researchgate.net/post/Is_any_one_working_on_new_techniques_of_distilling_aromatic_plants_to_produce_essential_oils

Dear Vinesh

Check this thread for any other techniques.

https://www.researchgate.net/post/What_is_the_best_method_for_essential_oil_isolation_What_is_difference_of_hydrodistillation_clevenger_apparatus_and_steam_distillation#view=5512036dd767a663168b457f

Essential oil is extracted by physical means, viz. hydro-distillation, hydro-steam distillation, steam distillation, cold press etc. Other methods, which used solvent  to trap the aroma of the plant give extract, not essential oil.

Dear friends

i want to extract garlic and guava leaf essential oil for sulfur compounds, please give any suggestion and reference for my work.

thank you

mathan

There are so many such kind of plants or trees where these all above said methods fails to get desired organic materials

steam distillation use for extraction essentail oil in plant

best regard

Commonly used is soxhlet extraction. You can vary your solvents for better yield based on the properties of your sample.

we have procedure for essential oil extraction -- if you need to it ... we send it to your email..... best regard