Is There Actually Fruit In A Fruit Roll-Up?

If you were alive in the 1980s and '90s, then you remember the glory days of fruit snacks. Some of them were gummy. Some of them gushed. And some of them were oddly stringy. But the undisputed champion of fruity deliciousness was the snack that rolled. General Mills' legendary fruit roll-ups have been a part of kids' lunches and snack times since 1983, and over the years, they've had their sticky fingers on all sorts of triumphs and controversies. But how were they invented? And exactly how much "fruit" is rolled into that cellophane wrapper?