Bertie Bott's Every Flavor Beans were created by inventor Bertie Bott quite by mistake. His original purpose was to create tasty candies from food but he accidentally included a pair of dirty socks in his experiment. Bertie recognized the sales potential of a candy that presented a "a risk with every mouthful!"
According to Ron, there are ordinary flavors like chocolate and peppermint and marmalade, but also more adventuresome ones like spinach and liver and tripe. George said he'd had a booger-flavored one. Dumbledore said that, in his youth, he ate a vomit-flavored one and was put off Bertie Bott's Beans for quite a while. Eventually he tried what he thought might be a "nice toffee," only to discover that the flavor was actually ear wax.
Bertie Bott's Every Flavor Beans are a popular sweet for kids at Hogwarts. They buy them from the lunch trolley on the Hogwarts Express and from Honeydukes in Hogsmeade. They give them for Christmas gifts and as gifts when someone is ill and in the hospital wing. Bertie Bott's Beans are sold in bags.
Source:
Harry Potter Lexicon
