The Kentucky Derby and the Mint Julep go together like a horse and the drink you traditionally consume while watching said horse race – and it's been like that for so long that it's easy to forget it wasn't always so. The modern, bourbon-drive julep was once a cognac, brandy, and rum drink sipped out of ordinary glass cups. Then southerners got their hands on it and switched out the ingredients and the glasses.

"By the middle of the 19th century, bourbon became established as a popular American spirit and became the base of the mint julep," says Dale DeGroff, the founding president of The Museum of the American Cocktail. "In the 1862 edition of 'BonVivant's Companion,' Jerry Thomas speaks about the Julep as a peculiar American beverage introduced to England by Captain Marryatt." The Captain, an officer in the British Navy and inventor of maritime flag signalingfavored sweeter liquors and "pounded ice," but juleps only took off in Kentucky when local bourbon was added. The refined 19th-century drink became a 20th-century blockbuster. It just needed to improve its packaging.

"Real julep cups have initials stamped on the bottom that tells you who was president at the time they were made," says Chea Beckley, Beverage Director at Louisville's Proof on Main. "They are given as gifts for special occasions and passed down within families." 

The purpose of the cups isn't immediately clear to most drinkers because they are holding them wrong. Julep cups should only be held by the top or the bottom so that the crushed ice inside them can create a frost on the outside. The whole thing is, as Simon Bolivar Buckner, Jr., a Lieutenant General and Kentucky native wrote in 1937, about the process. "By proper manipulation of the spoons, the ingredients are circulated and blended until nature, wishing to take a further hand and add another of its beautiful phenomena, encrusts the whole in a glistening coat of white frost," Buckner Jr. explained in a letter to a superior officer. "Harmoniously blended by the deft touches of a skilled hand, you have a beverage eminently appropriate for honorable men and beautiful women."

"Proper manipulation" takes a bit of practice. Beckley recommends lightly pressing mint leaves with the back of a spoon or a muddler, then adding simple syrup, packing the glass with crushed ice and pouring bourbon over the mix. If you really want to get into it, you can purchase collectible glasses from Churchill Downs itself. The institution's owners have embraced the association with the julep and spent the last several decades profiting from it. Over 120,000 juleps will be served at the track over the two-day race period and each one will be made with care. As for whether it will be consumed with care from a frosted glass, that's a different story.