The Only Temperature Frostys Should Be Served At, According To Wendy's

When Wendy's first hit the scene in 1969, it only had five menu items, according to the chain: hamburgers, chili, French fries, drinks, and the unprecedented Frosty. In a time of fast-food giants like McDonald's, KFC, and A&W, Wendy's strived against the odds to make a name for itself by touting the freshest ingredients, iconic square beef patties, and the one-of-a-kind chocolate Frosty.

The Frosty is a modern marvel of food science and a fast food industry hall-of-famer along with greats like the Big Mac and the Crunchwrap Supreme. Some claim the Frosty's key to popularity is its texture, a proverbial missing link between rich, creamy soft serve and frothy milkshakes. But achieving this coveted, now-classic balance and consistently delivering an incomparable product requires specialized equipment and proprietary recipes. Most importantly, for the integrity of the dessert as well as the Wendy's franchise, it must be served at precisely the right temperature.     

Occupying the liminal space between shake and soft serve, the Frosty was born from founder Dave Thomas' desire to create "a dessert on the menu that's so thick you had to eat it with a spoon," said the former executive vice president Ian Rowden. That vision was seen to fruition by Ohio-based food service equipment distributor Fred Kappus, says the chain's History of the Wendy's Frosty. When Kappus was asked to assist in the development of a frozen dairy dessert for Wendy's menu, he recalled a frosted malt concoction from a racetrack in 1960s Cleveland. This nostalgic treat's not-so-secret formula served as the inspiration for combining chocolate and vanilla to get a smooth, malty flavor.

Once Kappus and his team got the recipe together for the flavor, though, they had to manage procuring ingredients, stocking machinery, and coordinating transportation. This was all a lot easier when all six Wendy's restaurants were located in and around Columbus, Ohio, where they briefly outsourced their ice cream from a popular soft serve shop in the city. But according to the History of the Wendy's Frosty, as the chain expanded, they needed to switch gears, so Wendy's went to dairy recipe and mix specialist Tom Kullman to develop the Frosty formula that created the distinct flavor we know today. 

But a malty flavor and proprietary ingredients aren't the only things setting the Frosty apart from its peers. More of the mystery of the Frosty was revealed during an episode of Food Network's Unwrapped, where Wendy's demonstrated their specialized frosty machines that combine the functions of soft serve and shake machines. These machines, still supplied by the Kappus company to this day according to Wendy's, have a freezing chamber like a shake machine that uses rotary blades to continuously churn the Frosty mix. But these hybrid Frosty machines are also equipped with the refrigeration system of a soft-serve machine, giving the frosty its signature texture.

In order to achieve (and maintain) the perfect balance of smooth, creamy soft serve and light, fluffy milkshake, Wendy's stated in a 2006 press release announcing the addition of vanilla frosty to the menu that these specialized Frosty machines are designed to serve the drink "at a temperature of between 19 to 21 degrees" Fahrenheit in order to keep the mixture thick and retain optimal texture. With Kullman's perfected Frosty recipe and Kappus' specialty Frosty machines, Wendy's was able to expand far beyond its Ohio roots and serve perfectly churned and chilled Frostys worldwide.