The essential oil content of clove buds, stem and leaves is on average 17%, 6% and 2.5%, respectively.
Water or steam distillations still are popular for the production of clove oil. The first method yields essential oil for perfumery and flavour purposes, and the oil contains 85 to 89% of eugenol. The second method, on the other hand, yields, strong oil, rich in eugenol (91-95% by volume).
Before distillation, the clove buds are milled and must be distilled immediately, to prevent loss of oil by evaporation.
The steam produced in a boiler is introduced into a vessel which contains the buds and water. The buds are located on a grid placed at a certain distance above the level of the water which fills the bottom of the vessel. The water is vaporized indirectly, by steam flowing in a pipe coil submerged by the water. The water vapor plus the distilled oil coming from the evaporator vessel is recovered in a separate water cooled condenser. This mixture flowing out of the condenser is separated by decantation in a Florentine flask, in which two fractions, one lighter, the other heavier, than water are separated. The two fractions must be remixed after water is decanted.
The distillate water should be redistilled to recover all the dissolved oil extracted from the clove by distillation. This process is called cohabation. Finally, the clove oil is packed and dispatched for sales.
Clove oil processing does not cause environmental pollution. The residues of buds after distillation can be dried and used as fuels and their ashes can be used as fertilizers. The water waste after being separated perfectly from the oil does not damage the environment.
- Evaporator vessels
- Condenser (water cooled)
- Florentine flask
- Cooling tower
- Submersible pump
- Boiler system Grinding unit