With the media coverage on Panera and Chipotle regarding their preference for using “antibiotic free” meat, an associate professor at Iowa State University questioned the difference between the two products.

Dr. Scott Hurd, associate professor at Iowa State University, addressed the topic on his blog earlier this month. Dr. Hurd questioned if there was a difference, other than price, between conventional meat and antibiotic-free meat in regards to food safety.

From his post earlier this month titled, “Is antibiotic free really healthier?” Dr. Hurd addressed whether antibiotics, referred to as residues, are in the meat consumers eat. Due to the withdrawal period leading up to slaughter, Hurd says no illegal residues remain in the animal’s system at processing, leaving virtually no traces of antibiotics in U.S. meat.