Extraction Technologies For Medicinal And Aromatic Plants - Unido

EXTRACTION TECHNOLOGIES FOR MEDICINAL AND AROMATIC PLANTS
are inexpensive, easy to construct and suitable for fi eld operation. These
are still widely used with portable equipment in many countries.
The main disadvantage of water distillation is that complete
extraction is not possible. Besides, certain esters are partly hydrolyzed and
sensitive substances like aldehydes tend to polymerize. Water distillation
requires a greater number of stills, more space and more fuel. It demands
considerable experience and familiarity with the method. The high-boiling
and somewhat water-soluble oil constituents cannot be completely vaporized
or they require large quantities of steam. Thus, the process becomes
uneconomical. For these reasons, water distillation is used only in cases in
which the plant material by its very nature cannot be processed by water and
steam distillation or by direct steam distillation.
Figure 7: Clevenger-type laboratory-scale hydrodistillation apparatus
1.3.5.3.2.1.1 Traditional Method of Producing Attar Using Hydrodistillation
Floral attars are defi ned as the distillates obtained by hydrodistillation
of fl owers (such as saffron, marigold, rose, jasmine, pandanus) in
sandal wood oil or other base materials like paraffi n.
Attar manufacturing takes place in remote places because
the fl owers must be processed quickly after collection. The apparatus and
equipment used to manufacture attar are light, fl exible, easy to repair, and
have a fair degree of effi ciency. Keeping in view these facts, the traditional
“deg and bhapka” process has been used for centuries and is used even
now with the following traditional equipment (Figure 8).
• Deg (still)
• Bhapka (receiver)
•
Chonga (bamboo condenser)
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