CONCLUSIONS-Apparatus of Extraction

CONCLUSIONS


It might be worthwhile to review briefly the advantages and disadvantages of the various methods of manufacturing natural flower oils.
1. Steam Distillation of flowers yields volatile oils for example oil of neroli bigarade, rose, ylang ylang. Not all types of flowers, however, can be processed by hydrodistillation, because boiling wr,ter and steam have a deteriorating influence upon the rather delicate odoriferous constituents. The flowers of certain plants yield no oil at all when distilled, and hence must be processed by methods other than distillation.
2. Enfleurage (extraction with cold fat). This method is carried out only in France, where it is still practiced, but on a much smaller scale than in former years. The method is restricted to those flowers (jasmine, tuberose, and a few others) which, after picking, continue their plant physiological activities in forming and emitting perfume. Enfleurage, in these cases, gives a much greater yield of flower oil than other' methods. Despite this advantage, enfleurage has lately been replaced by extraction with volatile solvents because enfleurage is a very delicate and lengthy process, requiring much experience and labor.
3. Maceration (extraction with hot fat). This process used to be applied to those flowers which gave a very small yield by distillation or by enfleurage. Maceration, however, has lately been almost entirely superseded by the modern process of extraction with volatile solvents.
4. Volatile Solvent Process. Of general application, this process is today applied to many types of flowers, and carried out in several countries. It is technically the most advanced process, yielding concretes and alcohol soluble absolutes, the odor of which truly represents the natural flower oil as it occurs in the living flowers, or in the plants.

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