Why Lime Is A Crucial Component Of Traditional Tacos

There's a reason why James Beard Award Winner Rick Martinez, one of the most trusted voices in Mexican cuisine, calls skipping the lime on your homemade taco "a huge mistake". Lime doesn't just add a bright burst of acidity to your tacos. This vibrant green citrus is an essential, unskippable part of authentic Mexican cooking.

To understand why, we have to wind the clock back. It's around the 16th century, and Spanish conquistadors, along with European settlers, were flocking to the New World on ships. Aboard, they brought with them not just armor and horses, but also lime seedlings. These tart fruits made their way to Spain through trade, where their peculiar tartness became greatly popular. When the conquistadors transported them to the New World, the seedlings quickly acclimated to the tropical climate of Mexico. Before long, lime crops were flourishing and became a huge export for the colony.

Since limes are so widely available and plentiful, they're a low-cost ingredient for Mexican chefs to use in their dishes. It's so popular that you can give any dish a squeeze of lime, and not only does it blend in perfectly, but it also takes the tasting experience of that dish to the next level — and tacos aren't an exception.

For the most authentic flavor possible, you can't just pick any kind of lime to squeeze — it has to be a Key lime. While you might know this type of lime from those famous Key lime pies, they actually have another name: Mexican limes. These are the exact same citrus fruits that Spanish settlers brought to Mexico all those centuries ago.

The limes you typically see at the grocery store are called Persian limes, and they're very different from the Key limes that are commonly used in Mexican cuisine. They're bigger, with thicker, greener skin, but more importantly, they taste a smidge more mellow than Key limes — great for Brazilian lemonade, but you'll need more than that to cut through all the rich, savory ingredients in a traditional taco filling.

That's where Key limes come in. The fruit is smaller with thinner, slightly yellowish skin, and the juice it carries is verifiably potent. Sharp, tart, and extra-aromatic with a tinge of bitterness. If there's one drawback, it's that they can be a bit difficult to find in the U.S. (they used to be grown in Florida, but these days, most Key limes are imported from South America). But if you can get your hands on them, you'll have the ultimate batch of tacos with just a squeeze.