Citrus (Hesperidic)

On 13 July 1709 Giovanni Battista Farina founded a company in Köln. Johann Maria Farina, of the same family, composed a citrus water and named it after the city: Eau de Cologne. According to the German Patent and Trade Mark Office (DPMA), Johann Maria Farina gegenüber dem Jülichs-Platz is the oldest perfume manufacturer still operating. The Farina house in Köln is now a fragrance museum.

The Eau de Cologne formula rests on citrus oils, orange flower, petitgrain and herbs such as lavender and rosemary, diluted in alcohol at a low concentration. The name Eau de Cologne later became the name of a concentration and a style, no longer tied to one maker.

In 1853 Pierre François Pascal Guerlain composed Eau de Cologne Impériale for Empress Eugénie. In 1966 Dior's Eau Sauvage, composed by Edmond Roudnitska, combined citrus with herbs and used Hedione, a transparent jasmine-like molecule; it was the first commercially successful perfume to use Hedione. It is often cited as a landmark for the citrus aromatic branch.

The top is the largest part of a citrus composition. Citrus peel oils are mostly limonene, a fast-evaporating terpene. The character of each fruit comes from smaller constituents: linalyl acetate and linalool in bergamot, citral in lemon, nootkatone in grapefruit, dimethyl anthranilate in mandarin.

The heart extends the freshness with orange flower (neroli), petitgrain and herbs. Neroli and petitgrain both come from the bitter orange tree, one from the flowers, the other from leaves and young twigs. Lavender, rosemary, basil and mint pull the scent towards the aromatic side.

The base of a citrus is usually thin: musks, vetiver, light woods, sometimes moss. In modern perfumes synthetic musks and Hedione let the freshness last several hours, noticeably longer than a classic Eau de Cologne.

Cold-pressed citrus oils contain furocoumarins, of which bergapten and bergamottin are the most studied. They can cause phototoxic reactions when skin is exposed to sunlight. IFRA limits bergamot, expressed lime, expressed bitter orange, grapefruit and several other oils in leave-on skin products. Distilled citrus oils, such as distilled lime, and furocoumarin-free (FCF) bergamot contain far less furocoumarin.

Limonene, linalool and citral are among the 26 fragrance allergens that must be labelled in the EU. Limonene and linalool oxidise in air to sensitising hydroperoxides, so citrus oils need airtight, dark, cool storage. IFRA has a separate Standard restricting citral.

Regulation (EU) 2023/1545 adds bergamot peel oil, lemon peel oil, bitter orange peel oil, bitter orange flower oil and lemongrass oil to the allergen list. New products placed on the EU market after 31 July 2026 must be labelled according to the new list.

The SFP divides the Hesperidic family into seven subfamilies: A1 Hesperidic, A2 Spicy Hesperidic (Hespéridé Épicé), A3 Aromatic Hesperidic (Hespéridé Aromatique), A4 Floral Chypre Hesperidic (Hespéridé Fleuri Chypré), A5 Woody Hesperidic (Hespéridé Boisé), A6 Floral Woody Hesperidic (Hespéridé Fleuri Boisé) and A7 Musky Hesperidic (Hespéridé Musqué).

A1 corresponds to classic Eaux de Cologne. A3 is where citrus meets lavender, rosemary and basil. A7 reflects the role of synthetic musks in holding citrus on skin. The SFP website does not list perfumes per subfamily; examples here are indicative.

A classic-style Eau de Cologne can be built entirely from natural materials, since the original formula was. Bergamot, lemon, orange and mandarin form the top; neroli and petitgrain the heart; lavender or rosemary add an aromatic touch.

The weak point of a natural version is longevity. Without synthetic musks the base has to rely on vetiver, cedarwood or ambrette, and the citrus still fades within one to two hours. Grapefruit and yuzu can add different bitterness and sharpness to the top.

For leave-on products FCF bergamot or distilled citrus avoids the phototoxicity issue, and IFRA limits for citral and limonene must be checked. This page gives no formula percentages.