Two of the best known and nicest of the aromatic citrus fruits are lemon and lime. All cuisines worldwide use these fruits to give a sharp tang to both piquant and sweet recipes. The lemon is a citrus fruit with origins in India (not the Mediterranean, as is commonly believed). The Romans brought lemons to Europe, from India, in the first century AD. From there, the Moors took them to Spain and North Africa, as well as further east to China. Christopher Columbus took the lemon to America on his second voyage in 1493, and thus began the New World’s love of this fruit.

With their origin believed to be somewhere in Malaysia, limes are the most important citrus fruit in tropical regions. From Southeast Asia, the cultivation of limes spread to India, the Middle East, China and the West Indies. Attempts were also made to cultivate limes in Europe during the Middle Ages, but without success, since this fruit requires a much warmer climate such as that of the West Indies or Central America, where lime cultivation flourishes still today.

Lemons
Lemons are probably the most versatile fruit within the citrus family. Giving a sharp taste and aroma to every recipe, lemons can be used fresh, baked or dried, while both the flesh and the peel are edible. There are a number of lemon varieties; some are sharper than others, while some have a thinner peel, others a thicker one. When buying lemons, select ones that are dry and heavy for their size. They can be kept at room temperature for a week or stored in the fridge for 3 weeks.

Lime
There are a large variety of limes, all of which are very acidic. Limes from the West Indies or key lime is a specific variety of lime with a particularly strong aroma. This variety needs a very warm climate in order to flourish. The best known limes are from Tahiti, and are larger, but less aromatic. They may be stored in the fridge for about a week. When no longer fresh, the peel or the fruit becomes dry and its distinct green colour takes on a yellow hue.

The peel
The colourful and highly aromatic peel of either a lemon and or a lime is very often used in cooking. When a recipe calls for lemon or lime peel, make sure you remove only the coloured part of the peel and none of the flesh, which is bitter. Peel can be removed by grating or by using a peeler.


Kafir leaves
Kafir leaves from lime trees are butterfly shaped and are used extensively in Thai cooking. They have a characteristic, sweet aroma and are slightly sharp in terms of taste. These leaves can be used whole when simmered in curries and soups, or finely chopped in fried dishes and in salad dressings. They are available either fresh or dried in the Asian food section of your supermarket. When very fresh, they can be frozen for later use. Dried leaves are a poor substitute, however, for fresh ones. In fact, these little trees are easily cultivated and make attractive bushes. Snip off a few leaves as required for your particular recipes.


Juice
Both lemon and lime juice can be easily extracted. If the fruit is not fresh, it may have lost some of its liquid. This will make it much more difficult to extract the juice. Press with the palm of the hand on a work surface or a table to help the internal membranes release their juice.