International Centre for Aroma Trades Studies

Module 1

Foundation Science and Mathematics for the Aroma Trades

Abstract

Perfumery is both an art and a science and relies on the complex experimental process of combining aromatic materials for the creation of fragrances. These pleasant fragrances are created with the intention to provide a symbolic representation of an event or memory directly through their aromas or in conjunction with other senses. This report briefly reviews the scientific understanding required in the aroma trades profession.

Table of Contents

Introduction 4 Identification and characterisation of aromatic materials 4

Chemical structures and nomenclature 4

Structural isomerism 5

Stereoisomerism 5

Positional isomerism 6

Functional groups 7

Emulsions 8

Surfactants/Emulsifiers 8

Ionic charge 9

Chemical analysis 9

GC/MS 10

SPME/SBSE 10

Microbiology 11

Panel testing 11

Triangulation studies 11

Conclusion 12

References 12

Introduction

The core area of perfumery relies on the creation of fragrances. Fragrance creation is very much an experimental process and therefore a level of scientific understanding is required. Having this scientific understanding provides the perfumer with numerous avenues where they can demonstrate their creativity within the aroma trades profession.

The following sections review scientific areas, which an understanding of becomes beneficial the perfumer.

Identification and characterisation of aromatic materials

Perfume molecules are compounds comprising of mainly Carbon and Hydrogen, other elements such as Oxygen, Nitrogen, Sulphur and Phosphorus also occur frequently. Knowledge of this chemistry is vital to the perfumer as it is the basis from which these aromas are created and to how the compounds are named and classified. This info is essential for everything from purchasing the raw materials to what will happen to the final aroma product.

Carbon atoms are of unique character, in that they can bond with other carbon atoms to form chains, branched chains, ring structures, multiple-ring structures and chains bonded to rings in virtually limitless variety forming the backbone of most molecular structures.

Chemical structures and nomenclature

The four outer electrons usually form four covalent bonds. A covalent bond is one in which each atom contributes one electron to the bond. Formation of covalent bonds between a carbon atom and hydrogen atoms so that the molecule has a hydrogen atom at each corner of a regular tetrahedron leads to the formation of methane, the simplest organic compound.

Figure 1: Tetrahedral structure if methane

If one of the hydrogen atoms in a methane molecule is replaced with a second carbon atom carrying three further hydrogen atoms, we begin to create a series of compounds called alkanes.( Sell, C., 2008)

Alkanes are a group of compounds that comprise only of carbon and hydrogen atoms with only single bonds joining any two atoms together and they fit the general formula of CnH2n+2. Addition of a further carbon atom to ethane can ether be added to the first or second existing carbon atom to extend the chain. Symmetry of the molecule means that whichever carbon atom it bonds to, the overall molecular structure looks the same.

Upon adding further carbon atoms to this existing chain however, the overall molecular structure can look different depending on to which of the carbon atoms in the chain it bonds. Physical properties and chemical reactions of molecules depend on their shape. No reaction will take place between two molecules if the compatible parts cannot reach each other