The Real Difference Between a Florida Key Lime and a Regular Lime
Plus, can you substitute regular limes in Key lime pie?
They say you should eat several servings of fruit every day, so when you're craving a slice of Key lime pie, there's no reason not to give in. (Right? Right!) However, what happens if you're hankering for a slice of that sweet-tart Key lime goodness, but haven't made it to the Florida Keys to stock up on their local limes? Can you just run to the Piggly Wiggly for a regular lime instead or does lime pie just not have the same élan as Key lime pie? Will people snub your pie at the potluck if you make it with the supermarket variety? Probably not.
The limes grown in the Florida Keys tend to be small with a distinctive lime flavor that is tart, but not too acidic with a very distinct aroma. Grocery store limes, generally speaking, are Persian limes, which are larger and tarter than their Florida cousins. Key limes are smaller and contain more seeds than Persian limes, while Persian limes have a thick, bright green skin, and Key lime skin is thin and tends to be a little on the yellow side.
As for whether they have a different taste, the food testing pros over at Cooks Illustrated claim that there's a slight difference in flavor. "Sampled plain, the Key lime juice tasted slightly less tart and bracing than its Persian counterpart," they wrote. They even went so far as to run a lab test confirming that the juice from the Persian limes had a lower pH and higher acidity than the Key lime juice.
That distinction held true when they whipped up a batch of Key lime bars, too. They found that the bars made with Persian limes were tarter than those made with Key limes. Of course, some people like a dessert with a bit of bite and appreciate that extra acidity.
WATCH: Key Lime Pie Pound Cake
The main difference seems to be that it requires a lot more of that aromatic Key lime juice to make the famous pie sing. It is worth the elbow grease, though, to get that true floral Key lime flavor—unless of course you can't find Key limes. Then just swap for whatever you find at the grocery store and dig in because you want to get your recommended servings of fruit, don't you?