Perfumes and their preparation

by George William Askinson

Fig. 15.

The vapors rising from the still D pass through the helm C and the tube A into the worm K; the fluid condensed in the latter drops into the tin Florentine flask F, the aromatic water flowing from the latter passes back into the still D through the Welter funnel T and is distilled over again, so that the entire distillation can be effected with very little water, and it is continued until the water escaping from the Florentine flask is freed from oil and odorless.

When working with superheated steam, it is necessary to set under the funnel tube T a vessel twice the size of the Florentine flask, which is provided with a stop-cock above and below. The lower cock is closed, the vessel is allowed to fill with water from F, then the upper cock is closed, the contents being allowed to escape into D by opening, when the cocks are again reversed.

The use of superheated steam is important especially with material which gives up the contained oil with difficulty, such as woods.

Fig. 16.

For freeing the essential oil completely from water we use a so-called separating funnel (Fig. 16). This consists of a glass funnel T resting on a suitable support G, which is closed above with a glass plate ground to fit, drawn out below into a fine point S, and provided with a glass stop-cock H. The contents of the Florentine flask are poured into the funnel which is covered with the glass plate and allowed to stand at rest until the layer of oil O is clearly separated from the water W. By careful opening of the stop-cock the water is allowed to escape and the oil is immediately filled into bottles which are closed air tight and preserved in a cool and dark place.

Maceration (Infusion).

Some odors, like those of cassie, rose, reseda, syringa, jasmine, violets, and many other fragrant blossoms, cannot be obtained by distillation as completely or as sweet-scented as by the process of maceration which is in general use among the large perfumers in southern France. This process is based on the property of fats to absorb odorous substances with avidity and to yield them almost entirely to strong alcohol. According to the fat employed for the maceration of the flowers—a solid fat like lard or a liquid like olive oil—odorous products are obtained which are known either as pomades or as perfumed oils (huiles antiques). By repeatedly treating fresh flowers with the same fat the manufacturer is able to perfume the pomade or oil at will, and in the factories these varying strengths are designated by numbers; the higher numbers indicating the stronger products.

The process of maceration is very simple. The fat is put into porcelain or enamelled iron pots which are heated, in a shallow vessel filled with water, to 40 or at most 50° C. (104-122° F.); the flowers are inclosed in small bags of fine linen and hung into the fat, where they are allowed to remain for from one-half to two days. At the end of that time the bags are removed, drained, expressed, refilled with fresh flowers, and replaced in the fat. This procedure is repeated twelve to sixteen times or oftener, thus producing pomades or oils of varying fragrance.