I knew about AirHeads Xtremes, the super sour, rainbow-striped strips the company makes, as well as the mini versions of these strips, called "Bites," but the sour AirHeads bars are different.

It's present in products like Airheads Bites and Gummies. Food coloring like Red 40, Blue 1, and Yellow 6 are generally derived from synthetic (and unsustainable) petroleum-based sources.