Lemon -- a secret, subtle ingredient --is usually added in small quantities to recipes, yet adds notable flavor. While, it may seem like all lemons are created equal, there are actually different varieties of varying tastes and qualities. For example, Meyer lemons have a sweet flavor and work well in fruit salads, lemonade, chutney, and jams. Eureka and Lisbon lemons, are slightly bitter, and add a pleasant tartness to dressings and marinades. Here's some tips on how how you can spot the differences between varieties.
First thing to take note of is skin color. If the lemon's skin has an orange cast, then it is a Meyer Lemon. However, if it is bright yellow you will need to examine other aspects to determine what type of lemon you have.
Next, examine the skin texture. If the skin is very thick and pitted, with tiny holes in it, then you are likely dealing with a Eureka lemon. These lemons are very juicy and grown in large quantities for commercial use. If you purchased your fruit at a grocery store chances are you've got a Eureka. Lisbon lemons have smoother skin that tends to taper off to a pointed end.
Geographic region also plays a role--Eureka lemons are grown commercially and available in chain grocery stores everywhere, while Meyer lemons are most often available home grown in California. Limettas are a common variety found in home gardens in the U.S., India, and the Mediterranean, while Lisbons can be found in abundance at local produce stands in Florida.
Taste: Sweet vs. Sour
If you're still not sure, slice open the lemon and sample its juice. If the juice has a sweet taste, then the lemon is probably a sweet variety, like a Limetta or Meyer. Both of these types are actually hybrids; the Limetta is mixture of lemon fruit and the Mexican lime and the Meyer lemon is a cross between a lemon and orange. If the juice has a sour taste, then you probably have either a Lisbon or a Eureka. You will need to investigate further to determine which one you've got.
Seeds vs. Seedless
Finally, check the seeds. Lisbon lemons are seedless, while Eureka's have seeds.