Note (perfumery)

Notes in perfumery are descriptors of scents that can be sensed upon the application of a perfume. Notes are separated into three classes: top/head notes, middle/heart notes, and base/soul notes; which denote groups of scents which can be sensed with respect to the time after the application of a perfume. These notes are created with knowledge of the evaporation process and intended use of the perfume. The presence of one note may alter the perception of another—for instance, the presence of certain base or heart notes will alter the scent perceived when the top notes are strongest, and likewise the scent of base notes in the dry-down will often be altered depending on the smells of the heart notes.

The idea of notes is used primarily for the marketing of fine fragrances. The term is sometimes used by perfumers to describe approximately scents or the perfumery process to laypeople.

The concept of a perfume pyramid first appeared in the 19th century. François Coty, creator of the legendary Chypre fragrance (1917), is considered one of the pioneers who popularized the concept.

Fragrant materials are listed by Poucher in order of volatility and are grouped under respective evaporation coefficients (perfume notes) that range from 1 to 100.

Top notes are otherwise called the head notes.

Perceived immediately upon application of a perfume, top notes consist of small, light molecules that evaporate quickly. They form a person's initial impression of a perfume and thus are very important in the selling of the product. The scents of this note class are usually described as "fresh", "assertive" or "sharp". The compounds that contribute to top notes are strong in scent, very volatile, and evaporate quickly.

Although not as saliently perceived, the heart and base-notes contribute much to the scent in the top notes.

Citrus and ginger scents are common top notes.