Almond

Bittersweet and marzipan-like, with a hint of cherry and warm pastry.

Botanically, the almond is not a nut but the seed of a stone fruit from the rose family – related to apricot, peach and cherry. Its home is southwest Asia, with Iran regarded as the most important centre of origin. A distinction is made between the edible sweet almond and the bitter almond (Prunus dulcis var. amara), which is rich in amygdalin. Today California is the world's most important growing region. Because most of the varieties planted there cannot fertilise themselves, the crop depends on pollination by honeybees.

The typical scent is not yet present in the almond kernel itself. The bitter kernels are first pressed, releasing a mild, fatty oil. The remaining press cake is ground and steeped in water: now the kernel's own enzyme system, emulsin, splits amygdalin into sugar, hydrogen cyanide and benzaldehyde. Steam distillation then yields the essential bitter almond oil, which in its crude form contains several per cent of hydrogen cyanide. For perfumery and flavours the hydrogen cyanide is removed, leaving an oil of around 98 to over 99% benzaldehyde. Today the raw material is mostly apricot kernels, which share the same chemistry. Far more often than the natural oil, however, synthetic benzaldehyde is used.

Benzaldehyde gives compositions the unmistakable bitter almond and marzipan tone with a cherry facet and is a basic building block of gourmand accords. It is often flanked by heliotropin (C₈H₆O₃, sweet and powdery, heliotrope-like with hints of cherry and vanilla) and coumarin (hay-like, vanilla-like), which make the almond note seem softer, more powdery and warmer. In our range, almond appears in 37 fragrances, 17 in the top, 12 in the heart and 8 in the base note.

Gourmand · Bittersweet · Top and heart note

The almond tree blossoms in early spring, often before its leaves appear; the fruit ripens into autumn. As kernels and benzaldehyde store well or are produced synthetically, the almond scent is available all year round.

In our fragrances, it often appears alongside Vanille, Sandelholz, Tonkabohne, Jasmin, Moschus, Kirsche, Bergamotte.

Almonds are among the earliest crops of the Near East: cultivated almonds appear in the Early Bronze Age, and Sumerian texts from the 3rd millennium BC record almond oil, used mainly for anointing and sometimes scented. Well-preserved almonds lay in the tomb of Tutankhamun (c. 1325 BC). The scent was deciphered chemically in the 19th century: the French pharmacist Martrès obtained benzaldehyde from bitter almonds, in 1830 Robiquet and Boutron-Charlard isolated amygdalin, and in 1832 Friedrich Wöhler and Justus von Liebig first described the preparation of benzaldehyde. Bitter almond oil has long flavoured baked goods, marzipan and liqueurs.

• Sweet almonds owe their mildness to a single point mutation in the bHLH2 gene that blocks the formation of bitter amygdalin.
• In the Bible, Aaron's rod brings forth blossoms and ripe almonds overnight – a sign meant to mark him as the chosen priest.
• Nitrobenzene used to be called “false bitter almond oil” – a toxic substance that also smells of almonds but has nothing to do with the almond.

Bitter almond kernels store amygdalin (C₂₀H₂₇NO₁₁), a so-called cyanogenic glycoside. Only when the tissue is destroyed does an enzyme cascade begin: a first enzyme splits off glucose to form prunasin, a second releases mandelonitrile, which finally breaks down – spontaneously or enzymatically – into benzaldehyde (C₇H₆O) and hydrogen cyanide. In measurements, bitter almonds contain around 33 to 54 grams of amygdalin per kilogram, sweet ones usually only a few milligrams. The difference comes down to a single building block: in the sweet almond's transcription factor bHLH2, a point mutation has swapped one amino acid (leucine for phenylalanine), so that two cytochrome P450 genes of amygdalin synthesis are no longer read.