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The topic of this article is of a real-life subject that has been mentioned "in-universe" in a canon source. The Harry Potter Wiki is written from the perspective that all information presented in canon is true (e.g., Hogwarts really existed), and, as such, details contained in this article may differ from real world facts.
Mint humbugs, or Peppermint humbugs (also known as "Everton Mints" after the Liverpool suburb which is one place they were made), is a peppermint-flavoured Muggle confectionery, often eaten in winter, given the fact that many people get colds and Tonsillitis. They have a distinctive black-and-white striped pattern on them.
During the Welcoming Feast at Hogwarts in 1991, a bowl of mint humbugs were part of the main course. Rubeus Hagrid, a half-giant, Keeper of Keys and Grounds and Care of Magical Creatures Professor with very little knowledge of Muggles, owned a few mint humbugs which he kept in the pocket in his jacket.