Beaver butts emit goo used in vanilla flavored foods

Beavers are among the largest of the rodents.
(Joel Sartore/National Geographic)

Next time you pick up a vanilla candy, think twice. A chemical compound used in vanilla flavored foods and scents comes from the butt of a beaver.

Castoreum comes from a beaver's castor sacs, located between the pelvis and base of the tail. Due to its proximity to the anal glands, the slimy brown substance is often mixed with gland secretions and urine.

"I lift up the animal's tail," Joanne Crawford, a wildlife ecologist at Southern Illinois University told National Geographic. "I’m like, 'Get down there, and stick your nose near its bum.'"