What are the olfactory notes of a perfume?

Author: Redazione Date: 10 March '23 Category: Perfume World

What are the olfactory notes of a perfume? Let’s find out together.

Perfumery is an art form that mobilises our sense of smell, and olfactory notes are the building blocks of that art. When we smell a perfume, we don’t perceive a single aroma, but rather a whole range of scents which combine to create a unique olfactory profile. These are properly known as olfactory notes.

They’re nothing more than the individual raw ingredients of a fragrance. They can be extracted from natural sources or synthesised in a laboratory. It’s these notes that make up the formula for a perfume, giving it balance, differentiating between one fragrance and the others, ranging from floral to fruity, spicy to woody, and enabling a perfume to last for a longer or shorter period of time.
These notes go together to make the olfactory pyramid, a concept that helps define and classify each perfume’s characteristics.

This very ancient technique was introduced by perfumer Aimé Guerlain in 1889. He was the first to use it, to describe
Jicky, now known as the “first modern perfume”.

Just like a rising musical scale, the olfactory pyramid is made up of three levels expressing the degree of volatility of the ingredients making up a scent, known in fact as notes. And the fragrance is the result of the mingling of those notes.

The notes in a perfume are divided into top notes, middle (or heart) notes and base notes. This classification, as has already been said, is based on their relative volatility, meaning the speed at which they disperse in the air. Or it can be based on their tenacity, referring to the length of time during which they remain fragrant, before fading away altogether: when we smell a perfume from a bottle or glass, what we encounter first are the fleeting head notes, then we reach the heart of the perfume, and the final impression is left by the base notes.

“The top notes are the first we perceive when spraying a perfume, the middle notes are the heart of the fragrance, and the base notes are its foundation.”

Top notes: an invitation to freshness

Top notes are the first ones we perceive when splashing on a perfume, and they’re instantly recognisable. They mainly bring feelings of freshness, and give the first impression of a fragrance, preparing the ground for the middle notes to shine.

They’re the most volatile of the three, because they evaporate more quickly; their perfume is short-lived and at its strongest just after application, disappearing in as little as the first 5 minutes. Top notes are also referred to as the opening notes, and are largely composed of citrus ingredients, such as lemon, bergamot, mandarin or grapefruit, or marine, herbaceous and aromatic notes. They are light, volatile and fresh. They arouse our feelings and surprise us, but they do not last, and are soon forgotten.

Middle notes: the beating heart of the perfume

Middle notes are also called “heart” notes because they are indeed the very heart of a fragrance. They’re seen as “sweet” and “balancing”. By their nature they’re neither fresh nor deep.

The true aroma of middle notes normally starts to reveal itself after 15 minutes, once the top notes have evaporated, and it can last up to a few hours. They’re the most complex and make up the majority of the fragrance. They’re excellent at linking the freshness of top notes to the warmth of base notes. A wide variety of ingredients belongs to this group, the majority of them being floral, but also spicy and fruity, such as jasmine, rose and blackcurrant.

Base notes: depth, warmth and persistence

Base notes, also referred to as dry-down, are the last to emerge and are the least volatile. They evaporate more slowly and last longer than the previous two categories. Their true perfume may need some time to reveal itself, but it can then remain in the air or on the body for days at a time, and especially on clothes and textiles.

They usually comprise deep, rich and woody ingredients, such as patchouli, vanilla or sandalwood. They may also contain balsamic and musky notes and are perfect for lending extra depth to the fragrance, against the lighter top and heart notes.

The role of olfactory notes

Olfactory notes form the backbone of perfumery. They’re essential because they help create a balanced and harmonious fragrance that’s pleasing on the nose.

Each note has different effects on our emotional and psychological being. They can stir emotions and memories, and remind us of a person, place or particular moment in time. They can also influence our mood. It’s not by chance that we often choose a fragrance on the basis of our state of mind or the specific occasion. But, most of all, the perfume we put on adds a suggestion of our very selves, which we then present to others.
For this reason, master perfumers take great care in selecting and blending the different notes, to create a unique, memorable and, in some cases, truly personal fragrance.

An understanding of the different olfactory notes and the way they’re used helps us gain a deeper understanding of the world of perfumery, but it can also prove helpful to us when choosing the perfect perfume for ourselves or for someone else.

If you’d like to learn more about essences, aromas and compositions, take a look at our list of perfumery-specific books, which we discuss here.

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