Among North Carolina frankfurter aficionados, the state’s signature bright red hot dog is a thing of pride and beauty. Distinctively tubular, the tradition of these vibrant hot dogs stretches back nearly a century and across multiple small-town manufacturers.

Red Dye No. 3, also known as erythrosine, is a synthetic food dye that gives foods and drinks a bright red color. It is also sometimes used in oral medicines and dietary supplements. It first was approved for use in food in 1907. It's made from petroleum.