In Florida, Color Tells You Everything About Key Lime Pie

For as long as we can remember, a sweet and tart Key lime pie has always come in that signature shade of light green. It's the color you find in most bakeries and seaside cafes, the one that has you immediately going: "That's a Key lime pie!" after one look. As it turns out, this is not the case everywhere. In its home state, Florida, an authentic Key lime pie is actually defined by a custardy yellow hue.

Contrary to common misconception, Key lime pie isn't green by default. This long-held belief stems all the way back to the early 20th century, when Florida tourism started booming, and the pie became a visitor staple. Tourists conflated the green color of Key lime with the color of the pie. Meanwhile, yellow versions were dismissed as many thought they had been made from lemon. As a result, sellers adapted by lacing it with artificial food coloring to match customers' expectations.

In truth, Key limes are only green at first, but later on turn yellow when they ripen, and the juice is often clear and colorless. This renders it impossible to achieve that green hue naturally. Realistically, Key lime pie is creamy yellow, primarily from the egg yolks that are mixed with sweetened condensed milk and lime juice. This is also the reason Trader Joe's Key lime pie is yellow, not green.

Having been around since the late 1800s, it's inevitable that the Key lime pie has gone through a lot of changes. Still, you can get as close to recreating an authentic Florida Key lime pie as possible by paying attention to important elements. Firstly, the crust. Stick to a graham cracker crust, preferably made from scratch. Ensure that it's a perfect balance of pie-crust-solid and tender-moist, with a buttery undertone that supports the filling's zesty vibrancy.

The lime, of course, is no less crucial. Nowadays, Persian limes are a common choice since they are easier to obtain than Key limes. For a genuine pie, however, there's no beating those good old Key limes. Similar as they may look to the untrained eye, the difference between a Key lime and a regular lime is clear in flavor and aroma prominence. Tart and zesty without too much acidity, with a citrusy aroma that comes to life on your taste buds, Key limes are the superior choice every time. If fresh fruits aren't available, help yourself to store-bought bottled juice.

Last but not least is the topping. In The New York Times, one 1978 recipe from Key West restaurant Pier House opted for meringue, which is whipped from egg whites, cream of tartar, and sugar, then baked along with the pie until its edges are nicely browned. However, some sources also claim that authentic Key lime pie doesn't use anything at all since the original recipe would have predated modern refrigeration. In which case, a few slices of lime or grated zest will do the trick.