Smaller and more delicate than lemons, limes are tart with a hint of sweetness. They are an essential ingredient in the cuisines of Southeast Asia, Latin America, Africa, the West Indies and the Pacific Islands.

Lime can be used in place of lemon in nearly any recipe. Twist a bit of the zest into cocktails or add thin slices to a summery punch. In tropical countries, fresh lime juice deepens the flavor of sweet, musky fruits like papaya and guava. Lime pickles accompany Indian curries, fresh lime juice infuses Cuban chicken soup, and lime wedges accompany Mexican beer.

Familiar grocery store limes are Persian limes. Smaller, rounder Key limes grow in southern Florida. With thin, leathery skin and an abundance of seeds, highly tart Key limes lend their name to the famous pie. They are available fresh only occasionally in specialty produce markets, but look for good-quality bottled Key lime juice in gourmet shops.

Selecting
Buy smooth, glossy limes that are plump and heavy for their size. Avoid any with dull skin or soft spots. Pick Persian limes with dark green rind. Fully ripe Key limes have a yellowish rind and green flesh.

Storing
Limes can be stored at room temperature for 3 to 5 days. More perishable than lemons, limes fare better in a plastic bag in the refrigerator. Exposure to light and air will rapidly diminish the amount and tartness of their juice. Store lime oil in the refrigerator.

Adapted from Williams-Sonoma Kitchen Companion: The A to Z Guide to Everyday Cooking, Equipment and Ingredients (Time-Life Books, 2000)