Found  /  Explainer

A History of Flavoring Food With Beaver Butt Juice

No, castoreum is not a cheap substitute for strawberries; it’s luxe, artisanal secretions from a beaver's rear end.

The American beaver trade brought castoreum back into the spotlight, this time as a perfume. The perfumer-historian Mandy Aftel described it to me as “kind of sexy, kind of dark”—the scent of Russian leather. “It’s what’s known as a base note,” she explained. “It’s deep under things, one of the last lingering notes you smell.”

Aftel, who also makes a line of chef’s flavorings, has not used castoreum in edible concoctions, but points out that other heavily scented animal glands and secretions—musk, civet, and ambergris—were luxury ingredients in Medieval banquets. The 15th-century Persian Ni’matnamah, knows in English as the Sultan’s Book of Delights, includes recipes for musk-spiced samosas and ambergris-and-rosewater puddings.

Castoreum began to be used in flavorings in the early 20th century, an era when flavor-makers were borrowing freely from perfumers’ toolkits. By the 1960s, it was being used in vanilla and fruity blends; a 1970s flavor textbook praised the “unusual notes” it added to strawberry and raspberry flavors. Castoreum could be found in beverages, baked goods, ice cream, candy, and especially in chewing gum. The Algonquins traditionally dusted their tobacco with dried castoreum, and, in the 20th century, so did cigarette manufacturers like Phillip Morris and RJ Reynolds; it gave Camels and Winstons a distinguished, luxe aroma.

Castoreum was never fake vanilla or fake strawberry—not exactly. It was used in tiny amounts, usually less than ten parts per million, adding depth, intricacy, and intrigue to flavor compositions. In this way, castoreum is a quintessential secret ingredient, something that made a flavor better and more interesting, while eluding recognition

In the 1980s, the use of castoreum in flavors began to lag. In 1982, according to the Flavor Extract Manufacturers’ Association (FEMA), 683 pounds of castoreum were used in flavorings in the US. In 1987, that had dropped to just under 250 pounds. FEMA couldn’t provide me with current figures, but confirmed that its use has “decreased significantly” since then. Tobacco industry memos suggest that cigarette makers have also largely abandoned the substance.

In some cases, genuine castoreum was probably replaced with cheaper synthetic chemicals. But the biggest problem with castoreum was not its price, nor its anal-adjacent origins. It’s that beaver butt is not kosher. If food companies wanted to earn the rabbinical seal of approval, any traces of castoreum in flavorings had to be nixed.