Key limes vs. Persian limes

Cooks Illustrated, an excellent cooking magazine that doesn't take advertising, did a comparison between Key limes and the common Persian limes. They didn't test them in cocktails, but they did compare them straight and in a Key lime bar desert recipe. The results were that in straight tasting some tasters found that the Persian limes were slightly more tart, but in the desert there was no clear difference, except that they had to squeeze 20 Key limes vs. only 3 Persian limes to get the same quantity of juice!

http://www.cooksillustrated.com/tasting.asp?tastingid=399&bdc=4788&extcode=N07EG3AH1

I searched for a past topic on this but didn't find an exact match (previous topics on juice squeezers and Mai Tais had diverged into some discussion of this), so I started a new one.

In cocktails I was always disappointed when I tried key limes. They were not only more tart, but had a lot of bitterness in them. Not to mention the hassle of squeezing way more limes to get the same quantity.

I squeezed a bagful of fresh key limes from Trader Joe's one day -- it just got silly after awhile. The juice was fine but it just took too long for such a small amount.

They make adorable garnishes, though! And the mini-spent-shells look cool in a Mai Tai.

I use the key limes all the time, I like the bitterness and tartness. When I squeeze them, I throw in about 3 halves at a time, goes a little faster..

I don't have a little squeezer for key limes...

I prefer Key limes to Persian limes, but in the Greater Washington area they are often hard to find. Fortunately, this year starting in the spring we've been getting them, so that's all I buy now until they can't be found anymore.

If you squeeze Key limes while they're still green they're definitely going to be very tart. Key limes aren't ripe until they turn yellow. Then, when you cut them open, they are yellow on the outside and on the inside... well...lime green. Yummy.

Here are a couple of links I posted a while back about Persian Limes and Key limes.

Mai-Kai uses key limes

Anybody have first hand knowledge if this is still the case? If not, I'll find out.

Reviving an old thread here to hopefully get some perspective on what limes are supposed to be used in cocktail drinks. Maybe it doesn't matter a lot taste wise. But when you see Trader Vic's recipe for a Mai Tai that calls for "Juice from one lime" you have to wonder if its juice from a Key lime or a Persian lime. It would certainly make a difference in the amount of juice that's supposed to be in a Mai Tai.

Using the limes' various pseudonyms makes it even more confusing. Key limes are also known as "Mexican limes" or "Bartender's limes." That said, I would think that a "Bartender's lime" would be named for the reason that it was used commonly by bartenders to make drinks.

But "Persian limes" are also known as "Tahiti limes" (even though the variety was created in California), which makes me wonder if it was called "Tahiti lime" because it was grown on that island or if because it was used in tropical cocktails.

Anyone out there with some good knowledge of lime usage in cocktails from the 1930s on?

EDIT: I want to be clear, I'm re-iterating some of the above great information from Gator Rob and The Gnommon, but bringing it more forward and placing a firm opinion on the matter. :)

I have been researching citrus for the past few years, and here are a few tidbits:

The Persian or Tahiti lime (c. latifolia) originated in the Mediterranean likely as a cross between a lemon or citron and the key lime (true lime: c. aurantifolia). It went to Portugal, then Brazil, then Australia, then to Tahiti and to us.

It was relatively unknown previous to WWII. So! If you use a lime in a pre-1945-ish recipe, you had better be using a true/key/Bartender's lime (if these things are important to you).

The Persian/Tahitian lime produces a higher volume per acreage, is easier to grow and harvest (less spines) and ships better than the true lime. It soon became the Default.

Key limes surpass Tahitian in about any use: The oils are more complex aromatics; The juice is more complex in flavor.

Also, they are the closest to 'oldest' citrus we have. The four source citrus from which most others originate:

1. Citron
2. Lime
3. Pomello
4. Mandarin

[ Edited by: Melintur 2010-11-22 15:38 ]

Thanks Melintur. Bartender's limes are what I kinda expected to be the proper lime for older recipes. Thanks for the confirmation. Now I need to get some (I think our local Vietnamese grocery carries them) and make a more authentic Mai Tai.

I use Nellie & Joe's Key Lime Juice as a back-up when I don't have, or run out of fresh Persian lime juice. I usually cut the amounts by 1/4 to account for the stronger taste of Key Lime juice. Much easier than squeezing fresh, and probably much more cost effective.

I think it makes more sense of a Mai Tai than currently prevailing recipes, and certainly what is served at Vic's. Most Mai Tai's are way too tart and you can't taste the rums. Juice of half a Key Lime might be a bit too little, but maybe juice of one is about what I use in my Mai Tai recipe.

Let me make this crystal clear to everyone on this site.

Key Limes should only be used once they have ripened to a nice yellow. Not green, not kinda yellow, but yellow. Once ripe, they are full of juice, nearly a full to at least three-quarters of an ounce of powerfully delicious juice.

I use Key Limes almost exclusively when my Key Lime tree is in season - twice a year for about two months at a time. My Mai Tais are superior in tasting, my Zombies, Beachcomber Rum Kegs, you name it, are all superior in taste. My Margaritas sing.

One last thing, you must use a sweetener when using Key Limes. Now for Tiki drinkers, this isn't a problem. Sweeteners are an accepted part of drink making. For everyone else use to sweet and sour mixes, you must use either simple syrup or agave nectar.

But I promise you, if you use a nice yellow Key Lime, the rewards will be worth it. But, it must be ripe. I can't say this enough. Sadly, Americans are keen on using "green' limes and this simply won't do for this type of lime. Unless it is yellow, don't drink the....