Alcoholic Extraits

(c) Alcoholic Extraits.

In the early days of perfumery, the fragment pomades were employed directly; later they were extracted with high proof alcohol, the alcohol dissolving the natural flower oil from the pomade. These alcoholic washings are called Extrait No. 36 when made from Pomade No. 36; they reproduce the natural flower perfume to a remarkable degree. 
 Sketch of a Battcuse for the extraction of flower concretes with alcohol.  (The agitation is in counter-rotary motion.)

 FIG. 3.23. Sketch of a Battcuse for the extraction of flower concretes with alcohol.
(The agitation is in counter-rotary motion.)
Since no heat is applied during the process of enfleurage and during the washing of the pomades with alcohol, the extraits contain the natural flower oil as emitted by the living flowers. The only disadvantage exists possibly in a slight fatty "by-note" which can be eliminated to a certain extent by freezing and filtering the alcoholic washings. This slight fatty "by-note" is not always objectionable, as it imparts a certain roundness and fixation value to the finished perfumes, especially in conjunction with synthetic aromatics.
In order to prepare the extraits, the pomades are usually processed during the winter months when the factories are not busy with other work. For this purpose the pomades are charged into so-called batteuses (Fig. 3.23), closed copper vessels heavily tinned inside and equipped with strong stirrers around a vertical shaft. Several batteuses are arranged in batteries, the stirrers of each battery being driven by a powerful motor. The work, which goes on for several months, is carried out in cool cellars in order to prevent loss of alcohol by evaporation. Each batch of pomade is stirred for several days, the usual process of methodical extraction being applied. The alcohol employed in the process travels from one batch of pomade to the next (constituting in turn the third, second and first washings of successive batches), until it becomes enriched with flower oil and is drawn off as the alcoholic extrait. For the last washing, fresh alcohol is used, which also, in its turn, becomes gradually enriched by the continuous process just described. When extended to a fourth and fifth washing, this method extracts the pomades so efficiently that the exhausted fat is quite odorless. Being useless for new enfleurage it is usually employed for the making of soap.
The fully circulated washing called "Extrait No. 36" is run through a refrigerator and cooled to well below freezing temperature, if possible to 15o, Most of the fat dissolved in the strong alcohol separates. The cold alcoholic solution (Extrait No. 36) is then filtered, also at low temperatures.
The quantity of alcohol to be employed for the washing of each batch of pomade is calculated with a view to obtaining, finally, 1 kg. of extrait per kilogram of pomade. Obviously some alcohol is lost by evaporation during the process of stirring.
The purified extraits reproduce the perfume of the living flowers remarkably well. In fact, during the nineteenth century these extraits were widely employed as bases of the classical French perfumes, and several conservative houses still continue this practice. Some of the well-known French perfumes undoubtedly owe their success partly to a high content of extraits. The washing of the pomades is carried out not only by the factories in Grasse but in some instances also by perfume manufacturers in Paris, London, Berlin and New York who possess the necessary batteuses and freezing apparatus.
Since World War I, however, most perfumers have discontinued the cumbersome practice of processing the pomades purchased in Grasse; besides, high custom barriers prevented the shipment of alcoholic washings from Grasse into foreign countries. For these reasons the Grasse manufacturers started to offer their extraits in a more concentrated and convenient form.

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