Two Colorado farmers admitted to causing the deadliest foodborne illness outbreak in a decade Tuesday. Jensen Farms, located in Colorado, was the source of the outbreak that killed 33 people nationwide and sickened seven in Missouri.

In front of a federal judge, brothers Eric and Ryan Jensen pleaded guilty for the listeria outbreak linked back to their cantaloupe farm. A sentencing hearing is scheduled for January.

Colorado State University food safety expert Mike Bartolo says farmers have learned from the massive outbreak. And the fact that the brothers now face a possible 6-year prison sentence could have a chilling effect on anyone that produces food.

“There’s still that element of risk," Bartolo said. "And people, when you have that severe of consequences, may not want to assume that kind of risk.”

The Jensen brothers are suing a private auditing firm that gave their processing equipment a clean bill of health just weeks before the outbreak was detected.