Does Castoreum Really Come From Beaver Butts?

Beaver backside
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Articles about a secretion that comes from the south end of a northbound beaver sometimes make the rounds in the social media world, so I decided to take a quick look at this question. The claim is that when we eat vanilla-flavored foods, we also ingest a little bit of this secretion.

Ew... gross. Are we really eating beaver butt goop when we consume vanilla-flavored foods?

Maybe a little bit. The substance is called castoreum, and it’s approved for use as a flavoring agent in the U.S. and elsewhere.

So it might be found in some baked goods, desserts and beverages.

Say That Again?

Castoreum as a flavoring agent isn’t a new thing; it’s been used since 1920, and it’s approved by the U.S. Food and Drug Administration, the Flavor and Extract Manufacturers Association, and the Council of Europe.

But don't worry -- just because it can be used as food flavoring doesn’t mean that everything that tastes like vanilla has castoreum in it. In fact, although I’m not exactly sure how much is used in food processing, but from what I’ve learned, it's rare. You’re much more likely to find castoreum in perfumes, cosmetics, and soaps (especially in men’s colognes).

I’m not sure if that makes you feel better or not…

Eww… So What is Castoreum?

Beavers have scent glands, called castors, which are situated on either side of the anus, next to the anal glands. This isn’t particularly unusual; lots of mammals have scent glands -- gerbils have scent glands on their bellies and cats have them on their heads, faces, paws and their behinds.

These scent glands secrete substances that the animals use to mark their territory. So when your cat rubs his face against your, leg he's marking you as his, and when a gerbil appears to be stretching, it's marking things with its belly.

But apparently if you’re a beaver, the best way to mark your territory is by rubbing your backside against a pile of mud, leaving a mixture of castoreum and urine as your signature.


So Who Collects the Castoreum?

Mostly trappers. North American beavers are trapped and skinned for their fur pelts, and the castors can be removed from the animals after skinning. Sometimes the castors are used to make a bait that attracts more beavers (and the creatures that normally prey on beavers), or they’re dried, graded by size and condition, then sold at auction. The castors are processed, and the castoreum is extracted and sold as a flavoring agent or fragrance ingredient.

How Do I Avoid Beaver Butt Goop?

Castoreum is a natural ingredient so you won’t see it listed as such on a food label. It sounds nasty, but it’s safe to consume. It’s rarely used anyway, but if you want to avoid it, you’ll have to give up heavily-processed and prepackaged foods that might have a vanilla flavor.

Which isn’t a bad thing. Most of these foods are high in sugar, fat, sodium and calories as well. So avoid anything that might have beaver butt goop in it -- choose fresh whole foods instead.


Burdock GA. "Safety assessment of castoreum extract as a food ingredient." Int J Toxicol. 2007 Jan-Feb;26(1):51-5. Accessed April 14, 2016.

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