Apple Candy comes in a variety of types, but perhpas top of mind is the classic hard candy apple, a historical staple of autumn festivals, traces its roots back to 1908 in Newark, New Jersey, where candy maker William W. Kolb reportedly invented the treat while experimenting with red cinnamon hard candy for a Christmas window display; the combination of a whole apple on a stick dipped in a hard, cinnamon-flavored sugar glaze was an instant, albeit accidental, hit. This original candy apple - often called a toffee apple outside North America—is distinct from the softer, stickier caramel apple, which came later, popularized in the 1950s using melted caramels.
For manufactured apple-flavored candies, the characteristic "green apple" taste, which is typically tart and sour, is often based on the flavor of the Granny Smith apple and is chemically mimicked using specific fruit esters, which are easier and cheaper to synthesize than the complex blend of compounds that make up a fresh apple's flavor. The popularity of green-colored apple candies is partly an industry decision to visually differentiate the tart apple flavor from the red color already associated with sweet berry or cherry candies. This flavor is globally popular, such as Peelerz Green Apple and Gummy Sour Green Apples.