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About this Article
Written by: Teresa Lai
Written on: April 23rd, 2012
Tags: lifestyle, health & medicine, chemical engineering
Thumbnail by: Big Stock/Big Stock
About the Author
Teresa Lai was a sophomore majoring in Chemical Engineering and hopeed to work in the health care industry in the future. She does not use perfume very often.
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Volume XIV Issue III > Follow Your Nose: Engineering in Perfumes
Most people view perfumes as delicate works of art, created with a meticulous hand and applied with a careful touch. However, the introduction of engineering into the analysis and creation of fragrances has mechanized the process more than ever before. The consequences of these new methods, both intended and unintended, have changed the industry irreversibly and provided an insight into the future of all cosmetics.

Introduction

The everyday routine for most women might be something like this: style your hair, brush your teeth, pick an outfit, and spritz a fragrance on your skin, the last of which happens quickly and without a second thought. However, for some scientists and engineers, perfume-making requires a more careful analysis. Perfumery, once thought of as an art, has been transformed into a scientific process in which natural scents are broken down into constituents and replicated with synthesized materials. Many in the perfume industry benefit from the engineering that makes it possible to replace regulated ingredients and to scientifically determine a fragrance’s quality. But others decry the ease with which companies can now make knock-offs and the death of what was once considered a secret art. The introduction of engineering into perfume-making has permeated nearly every aspect of the industry and will likely continue to change the character of fragrances for years to come.
Angela Andriot/Wikimedia Commons
Figure 1: Vintage Atomizer Perfume Bottle

A History of Fragrance

Various forms of fragrances have existed since 7000 B.C. These initial perfumes were usually made from gums, resins, oils, and plants. The uses went beyond cosmetics – often, perfumes acted as important items in religious ceremonies, funerals, and medical procedures, duties which are a far cry from the role of perfumes today [1]. Gradually, as international trade became more feasible, fragrances of different cultures spread around the world and perfume began seeping into other avenues of society, no longer restricted to religious ceremonies and medical procedures.
The process behind the perfumes we think of today began in the late 19th century, when perfumers diligently studied how to extract scents from flowers. Thus began in earnest the idea of perfumery as an art, an idea that prevails to this day (Fig. 1). Edmond Roudnitska, a French perfumer, compared the practice to making music: “You will have a simple fragrances, simple accords made from one or two items, and it will be like a two- or three- piece band. And then you have a multiple accord put together, and it becomes a big modern orchestra” [2]. Perfumery, on account of its long history and detailed creation process, became a craft for many perfumers. However, engineering is beginning to take a primary role in breaking perfumes down into an exact science.

Measuring A Feeling

Assessing a perfume’s quality would appear to be a highly subjective process. How can you quantify a fragrance’s musky odor, or its hints of floral character? One of the answers, according to engineers, is in perfume ternary diagrams. Traditionally, a perfume’s notes are broken down into three types: top notes, middle notes, and base notes. Top notes are the strongest flashes of odor that are detected just minutes after application. The middle notes, which remain for hours, are what the odor evolves into after the top notes have gone. The base notes, which serve to stabilize the top and middle notes, can last for days [3].
This information was combined with ternary phase diagrams, which are typically used in engineering and physical chemistry to describe the compositions and components of a substance. The result was the Perfumery Ternary Diagram, which suggests specific percentages for each type of note [4]. A ternary diagram is a triangle-shaped graph in which any point within the triangle provides information about the relative compositions of three components, each of which is represented by a side. In this way, someone could read the diagram and determine exactly how a perfume’s character has been developed.