If you've ever eaten a sour candy, you know that the taste is much different than a sour fruit, like a lemon. It's not a flavor that occurs in nature, but you probably aren't expecting a Warhead, sour ...

Trick-or-treaters demand it. Dentists despise it. Pop musicians have sung odes to it. Love it or hate it, candy is a cultural fixation — and it isn't going anywhere. In Candy: A Century of Panic ...