Kyoko Sakura
Celestial Guide
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Source - National Geographic
Nat Geo said:Beaver butts secrete a goo called castoreum, which the animals use to mark their territory. 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[...]
Instead of smelling icky, castoreum has a musky, vanilla scent, which is why food scientists like to incorporate it in recipes[...]
Because of its FDA label, in some cases, manufacturers dont have to list castoreum on the ingredient list and may instead refer to it as "natural flavoring." Yum.