While rarely consumed on their own, lemons make a major contribution to the flavours of many foods we eat. Although you wouldn't choose this tart citrus fruit for a snack, you might well squeeze some lemon juice over fresh fish and seafood, add a wedge of lemon to your tea, or grate some l lemon zest into your favorite cake mix. These fruits are packed with vitamin C, a vitamin whose deficiency can cause scurvy. Aside from supplying substantial amounts of vitamin C, the main benefits of lemons relate to their seasoning potential. By adding tart fresh lemon juice and lemon zest to recipes can reduce the amount of salt needed to enhance the flavours in rice, potatoes, salads, and cooked vegetables, while adding no fat and negligible calories.

Lemons probably originated on the Indian subcontinent, and depictions of lemons were found in 2nd and 3rd century Roman mosaics. It's likely that lemons were popularised in Europe at the time of the Crusades, and Columbus may have taken the seeds of the fruit to the New World (along with lime seeds) on one of his voyages. Citrus fruits, including lemons and limes, were established in what is now Florida by the 16th century.

Buying
These fruits should be firm, glossy, and bright, beautiful enough to be treated as ornaments in your kitchen. Lemons should be a very bright yellow, not greenish. A very coarse exterior may indicate an excessively thick skin, which in turn may mean less flesh and juice (large lemons are likely to be thick skinned); heavy fruits with fine-grained skin are juiciest. Avoid both hard, shriveled lemons as well as spongy, soft ones.

Storage
If you are planning to use lemons quickly, you can leave them in a basket at room temperature; they will keep for about two weeks without refrigeration. Lemons stored in a plastic bag in the refrigerator will keep for up to six weeks.

Preparation
To get the most juice from a lemon, the fruit should be at room temperature or warmer.Or place it in hot water or a low oven for a few minutes to warm it, or microwave it for 15 to 30 seconds. Then roll the fruit under your palm on the worktop 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, using your fingers to hold back the seeds. If you don't need all the juice at once, you can pierce the fruit with a toothpick or cocktail stick and squeeze the juice from the opening; "reseal" the fruit by reinserting the toothpick or stick.

Recipes often call for lemon zest, the yellow part of the peel. Wash and dry the lemon (a lot of lemons sold in the UK are waxed with chemicals to prevent post harvest disease during transport and storage). Use the fine side of a hand grater, a special zesting tool, a sharp paring knife, or a vegetable peeler to remove the zest carefully so as not to include any of the bitter white pith. A large lemon will yield about 3 to 4 tablespoons of juice and 2 to 3 teaspoons of zest.