Yeasty Dough Heats and Rises in Truck, Leaving Gooey Trail on Interstate 5

Mile after mile, drivers on the freeway in Tacoma, Washington noticed the sticky, beige substance oozing out of the large truck.

To some, it looked like foam. To others, some type of insulation. The goo was falling out of the open container truck in chunks, leaving a messy trail on Interstate 5 for miles.

The glutinous substance was actually bread dough, rising like dinner rolls in a pan. That afternoon, the truck driver had picked up the yeasty dough – leftover waste from a bakery – to take to a processing plant where it would be re-purposed as feed for livestock, according to Brooke Bova, public information officer for Washington State Patrol.

As the driver had been doing for years, he loaded up the truck with the plastic bags of dough, filling the truck bed with the same amount as always. But it was a particularly hot day, with temperatures in the mid 80s, and a particularly long commute, because of traffic from a nearby military base.

“It was kind of a comedy of errors,” Bova told The Washington Post.

The combination of the heat and yeast in the non-refrigerated truck must have caused the dough to swell and the plastic bags to burst, Bova said. As the dough expanded, it began seeping up and out of the truck and falling onto the road in clumps the sizes of basketballs.

The driver was on the road for more than an hour when he noticed the falling dough and pulled over.

Responding to a number of 911 calls, state troopers showed up and helped clear the large chunks of goo off the highway. Hearing the calls, Bova said, “I gotta go see this with my own eyes.”

Making her way down the interstate to mile marker 130, where the driver had pulled over, Bova saw the trail of dough, flattened on the road by drivers.

“Right when you think you’ve seen it all, you get dough on the freeway,” Bova said as she live-streamed a video of the gooey mess.

State troopers scooped the dough off the road and into a pickup truck, and the driver took the remaining dough to the feed processing plant.

“He was embarrassed,” Bova said about the driver. “He’s never seen anything like this.”

The dough did not present a hazard for driving, and caused no accidents, Bova said.

But the same could not be said for a similar sticky scene in recent memory. In November 2015, a Domino’s semi-truck carrying hundreds of pizza dough balls crashed into a bridge in Indianapolis, causing rising dough to ooze onto the highway.