As any Cosmo reader will tell you, it’s a well-tested truth that men love the smell of vanilla. Turns out though, that men may not be falling for a scent that reminds them of childhood, but for something else entirely: Castoreum a.ka. a fragrant, brown slime that comes from a beaver’s castor sacs, which are located pretty much where you expect them to be located.
The chemical compound that beavers use to mark their territory has a musky, vanilla scent, which is why some perfume makers incorporate the component into their products and food scientists add the all-natural ingredient into recipes. As one can surmise, the vanilla aroma is not typical of the area, but is a product of the beaver’s unique diet of leaves and bark, said Joanne Crawford, a wildlife ecologist at Southern Illinois University, speaking to National Geographic.
Collecting castoreum can be a tricky endeavor though. A beaver’s castor sacs are located between the pelvis and the base of the tail. Because of its close proximity to the anal glands, castoreum is often a combination of castor gland secretions, anal gland secretions, and urine. “You can milk the anal glands so you can extract the fluid,” Crawford said. “You can squirt [castoreum] out. It’s pretty gross.” That may explain why castoreum is not an especially common source of vanilla flavoring. According to Fenaroli’s Handbook of Flavor Ingredients, published in 2005, total annual consumption of both castoreum extract and castoreum liquid was around 250 pounds, undoubtedly because the milking process is unpleasant for all parties involved.
The U.S. Food and Drug Administration lists castoreum as a “generally regarded as safe” additive, and manufacturers have been using it extensively in perfumes and foods for at least 80 years, according to National Geographic and a study in the International Journal of Toxicology. Because the FDA considers the ingredient safe, in some cases, manufacturers don’t have to list castoreum on the ingredient list and may instead refer to it simply as “natural flavoring.” Apparently “gross” is not something the FDA quantifies.