Perfume character

Perfume character, i.e. does the perfume still smell the same or very close to that of a newly made product (allowing for some desirable maturation or ageing of the perfume in the product over a 1 or 2 week period) ... 

After 12 weeks of stability testing has been completed (and usually after an interim 4- or 6-week period), all the perfumed samples are assessed on odour and physical appearance. At Quest, scales of A-E for perfume character and 1-5 for odour intensity are used. The refrigerated sample (nominally 0°C) is treated as a standard, as perfume degradation is considered to be negligible at this temperature and is therefore rated as Al. The samples from the other conditions are... 

Chemical compounds having odor and taste number in the thousands. In 1969 a description of the odor characteristics of more than three thousand chemical compounds used in the flavor and perfume industries were described (41). The Hst of volatile compounds found in food that may contribute to odor and taste is even larger (42), and the Hst of all possible flavor compounds, including those that have yet to be synthesized, is greater than a thousand. Many different compounds have the same flavor character or quaUty, differing perhaps in their relative intensity but indistinguishable in the type of flavor they ehcit. The exact number of different flavor quaUties is not known, but it appears to be much less than the total number of compounds with flavor. 

Ethyl Salicylate.—The ethyl ester of salicylic acid resembles the lower homologue, methyl salicylate, in its general characters and perfume value. It is an oil of specific gravity 1 1372, refractive index 1-52338, and optically inactive. It boils at 234°. It solidifies at low temperatures, and melts at 1-3°. 

Benzyl Ginnamate.—The cinnamic acid ester of benzyl alcohol is a natural constituent of storax, tolu, and Peru balsams. It is a crystalline Bubstance with a characteristic sweet balsamic odour. It may be prepared by heating sodium cinnamate, alcohol, and benzyl chloride together under a reflux condenser. It is a useful ester where a sweet balsamic odour is required to be introduced into a perfume, especially cf the heavy type. It forms white, glistening prisms, which melt at 39°, and.decompose when heated to 350°. The best commercial specimens have the following characters —... 

R = H, C9H10O4, Mr 182,18, mp 130.5-131.6 °C, forms an off-white powder with long-lasting moss odor, slightly reminiscent of oakmoss and strong seaside in character. It is used in small amounts to provide marine effects to perfumes. 

It can be used in almost all perfume types to give elegant floral diffusion without changing the fragrance character. Its stability allows application in soap, toiletries, and household products. 

Another approach to the reproduction of floral notes has come from the work of the creative perfumer based on the use of synthetic materials whose olfactory character may be similar in some respect to that of the flower being copied, whether or not they are known to occur in nature. Many of the floral bases created in this way, although frequently but pale reflections of the flowers themselves, have come to be among the most widely used building blocks of perfumery. 

It is important when beginning work on a floral base to start with as simple a formula as possible, containing only sufficient materials to establish the essential character of the note. This basic accord can later be embellished by the addition of modifying materials and naturals. The most effective floral bases, particularly when designed to be used as a major part of a perfume formula, are often comparatively simple mixtures containing no more than 15, and often fewer materials. More complicated bases, when used in this way or in combination with other florals, may often be the cause of "muddiness" and general lack of impact in the final product. 

Many hyacinth compounds are particularly disappointing in this respect, with the fine floral character being reduced to no more than a "green" effect when used in combination with other floral notes in the finished perfume. The most successful accords, whether they be those that are found in floral bases or those on which the great perfumes are founded, seem to be virtually indestructible wherever they occur. With experience students will learn the ways in which the various types of floral base perform in different types of composition. Most perfumers choose to work with only a limited number of bases, whose performance they are thoroughly familiar with and understand. 

Calls for matches that go beyond family resemblance and aim at closeness to a specific model entail technical, practical, and ethical problems. The technical problem lies in the fact that even with the help of GC/MS, far more effort is involved in creating a close rather than an approximate match. The difficulties are multiplied if the character of the perfume is considerably modified by the components of the product base and if, as is usually the case, the cost limits are well below the cost of the original fragrance. 

In a well-constructed fine fragrance the heart of the perfume needs to be contained within the lower part of the composition, since this part will remain on the skin for many hours after application. Many of these long-lasting materials, as pointed out by Carles, are rather unpleasant when smelled initially and it is part of the function of the modifiers and finally the top notes to subdue and round off the character of these products in the final accord. 

Another of the most valuable exercises that a student can do, and one for which we are grateful to our colleague Martin Gras, is to recreate the essential character of a perfume from no more than 10 or 12 materials. This teaches not only the underlying accords that go to make up the perfume but also shows what can be achieved with comparatively few materials. This technique is also invaluable when trying to simplify a new formula or trial match that has become overcomplicated and unworkable—to go back to the essential structure and to start again from there. 

Although a well-made perfume needs to be constructed around a strong and comparatively simple accord, it is the presence of a multitude of other materials that completes the full character of the fragrance, giving it the roundness and aesthetic quality. Of course we are not advocating complexity for its own sake, and the perfumer who continues to add more and more materials in the hope that they will somehow cover up the imperfections of his or her original accord is more than likely to be disappointed. The complexity of a perfume must be related to its overall structure with no material added just for the sake of complexity. Each one must be there for a purpose, making a contribution to the final accord that makes up the finished perfume. The perfumer should know how each material in the formula works in relation to a creative idea—or leave it out. 

This relation between simplicity and complexity in perfumery may be represented by the diagram in Figure 9.2 which shows that each material not only plays its part in forming the overall character of the perfume (at the outside of the circle) but also contributes to its internal structure and harmony. 

Bases may be thought of as the prefabricated building blocks of perfumery. They may be as simple as an accord between three or four materials or nearly as complicated as a complete perfume. A base should have a well-defined character, since it is an essential structural element of the perfume s composition. 

Perfumers vary widely in the extent to which they use bases in the creation of their perfumes. Some regard the making of bases as one of the most important aspects of their creative work. They embody in their bases their most original ideas, building them into the otherwise classical structure of their perfume to provide much of its essential character. Michel Hy used to tell his students that it could take him a year to make a good base, but once complete he could use it to make a perfume in a week. And sometimes he would do it in less. 

Some of the most successful bases contain quite simple accords of only two or three materials, perhaps dressed up with a number of auxiliary products. The combination of phenoxyethyl isobutyrate and dimethyl benzyl carbinyl acetate, used in many fruity notes, produces an unmistakable character that survives even when used in trace amounts in a finished perfume. Similarly an ambergris base, made from a simple combination of labdanum, olibanum, and vanilla, brings an unmistakable effect. Such bases, which the perfumer may create for him- or herself, are not only valuable building blocks in the creation of a perfume but are a convenient way of introducing trace amounts of materials that in combination make a special contribution to the character of the final composition. 

Yet another type of base is that in which the essential character of an existing perfume is recreated without developing the full complexity of the original. This can then be used to give a twist to the character of a new creation or as the starting point for a "within the area" match. Such bases, even if written out into the final formula, can be of special value in the creation of hybrid fragrances, such as between Anais Anais... 

Perfumery style today, demanding a greater initial impact based on a simpler type of formulation, has reduced the use of the type of base that represents a high proportion of the finished composition. But floral bases and those that bring a strong positive character to a perfume are still widely used, and a knowledge of them is an important part of a perfumer s training. 

Alliage, which is at least arguably a floral-chypre, and Chanel 19, a perfume belonging to its own genealogical family of intensely woody floral-green perfumes. These three perfumes have little in common except their green character, and even this is based on different combinations of materials. Beautiful, on the other hand, while reputedly derived... 

In this group we will be looking at four perfumes, predominantly floral in character, based on salicylates in combination with woody notes and musk. This underlying accord has proved to be one of the most successful in perfumery, providing the starting point for many varied and wonderful creations. 

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