Ice cream is young. For more than a thousand years, our ancestors had to settle for flavored snow — quick to vanish without modern refrigeration, and thus a luxury, reserved for the rich.

Sorbet was accidentally invented in the 16th century, when the Italian scientist Giambattista della Porta tried to freeze wine and wound up with boozy slush. Only in the late 17th century did someone have the grand idea of improving sorbet by using milk, “which first you must cook,” as noted in a recipe by Antonio Latini, the steward of a noble Neapolitan household.

But ice cream has always been part of American history — because our nation, too, is young. Thomas Jefferson wrote out a recipe for it in longhand, demanding “good cream” and a stick of vanilla, and served it encased in pastry to guests when he was president. While the French and Italians refined ice cream as an art, Americans made it the dessert of the people, building labor-saving machines that drove prices down.