Why Binturongs’ Pee Smells Like Buttery Popcorn

Imagine what a different experience it would be to walk into an public restroom rife with unflushed toilets and, instead of having the insides of your nostrils terrorized with the burning, putrid smell of stale urine, they were greeted with the warm, inviting aroma of hot buttery popcorn?

Who knows if they feel the same way about it, but that is exactly how the pee of a bearcat (a.k.a. binturong, if you’d so prefer) smells. As it turns out, the compound in bearcat pee that is responsible for this phenomenon is the same one that gives popcorn its uniquely wonderful fragrance.

A bearcat is not actually a cat, nor a bear, but a shy creature of the civet family. With sharp claws, it slowly but purposefully climbs through trees, splitting its time between napping and searching for snacks of rodents, small birds, and fruit.

Researchers from Duke University, eager to find out how it is that bearcats were blessed with such a tastily fragrant pee, studied 33 of them at the Carolina Tiger Rescue, a nonprofit wildlife sanctuary in Pittsboro, North Carolina. After identifying the different chemical compounds in the bearcats’ urine, they pinpointed the buttered-popcorn scent culprit as 2-acetyl-1-pyrroline, or 2-AP.

In popcorn, 2-AP is created when heat jumpstarts Maillard reactions between the sugars and amino acids in the corn kernels. The same phenomenon is responsible for the inviting aromas of toast and cooking rice. 2-AP is also the compound that gives jasmine rice its appealing floral scent. “The compound was in every binturong we studied, and at relatively high concentrations,” said lead author Lydia Greene in a press release.

The study was published this week in the online journal The Science of Nature–Naturwissenschaften.

Their aromatic urine serves a distinct purpose. Though these shaggy critters generally keep to themselves and only very rarely put in facetime with others, that doesn’t mean they don’t communicate with other bearcats. This they do through pee, albeit in a fairly unrefined manner.

Bearcats pee squatting in place, thoroughly inundating their back feet and bushy tail in the process. So they all end up smelling like popcorn. As they gingerly move among the trees, their broom-like tail paints all the foliage with that smell and lets all other binturongs know whose territory it is.

Let sleeping binturongs lie