Fruit and vegetables for health

While rarely consumed on their own, limes make a major contribution to the flavours of many of the foods we eat. These flavour packed fruits are also loaded with vitamin C, which among its other health promoting virtues also prevents a disease called scurvy. In the 18th century, the Royal Navy ordered ships going on long journeys to carry limes for their crew (hence the nickname "limeys" for British sailors), although, at the time, it was not understood exactly how the fruit prevented scurvy. It wasn't until vitamin C was discovered in 1932 that scientists understood that it was the vitamin, not the fresh fruit itself, that protected against the disease.

Aside from supplying substantial amounts of vitamin C, the main benefits of limes relate to their seasoning potential. Slightly sweet, tangy lime juice and lime zest can help you cut down on the amount of salt you add to dishes you prepare. They also enhance the flavour of foods such as rice, potatoes, salads, and cooked vegetables while adding no fat and only negligible calories.

Limes probably originated on the Indian subcontinent. It seems likely that limes (and lemons) were popularised in Europe at the time of the Crusades, and Columbus may have taken the seeds of both fruits to the New World on one of his voyages. Citrus fruits, including lemons and limes, were established in what is now Florida in the 16th century.

Shopping
Limes should be firm, glossy, and bright. They should be dark green: Limes turn from green to yellow as they ripen, but it's the immature fruits that have the desirably tart juice; yellowish limes have an insipid flavour.

A very coarse exterior may indicate an excessively thick skin, which in turn may mean less flesh and juice; heavy fruits with fine-grained skin are juiciest. Avoid both hard, shriveled limes as well as spongy, soft ones.

Storage
While lemons will keep for about two weeks without refrigeration, limes are more perishable and should be refrigerated immediately. Limes stored in a plastic bag in the refrigerator will keep for up to six weeks.

Preparation
To get the most juice from a lime, the fruit should be at room temperature or warmer; if need be, place it in hot water to warm it, or microwave it for 15 to 30 seconds. Then roll the fruit under your palm on the countertop until it feels softened.

There are lots of gadgets for juicing citrus fruits—juicers onto which you press the fruit, reamers you twist into the fruit—but it's simplest to halve the fruit and squeeze it in your hand. If you don't need all the juice at once, you can pierce the fruit with a toothpick and squeeze the juice from the opening; "reseal" the fruit by reinserting the toothpick.

Recipes often call for lime zest—the flavorful colored part of the peel. Wash and dry the fruit, then use the fine side of a hand grater, a special zesting tool, a sharp paring knife, or a vegetable peeler to remove the zest. When grating or paring the zest from a lime, do not include any of the bitter white pith along with it.

A large lime will provide 2 to 3 tablespoons of juice and 1 to 2 teaspoons of zest.