A good lemon will feel heavy for its size and have a finely textured skin.
As the lemon ripens, the skin will become thinner and more juice will develop. If you are going to use the zest it is important to buy unwaxed and, preferably, untreated organic lemons. Otherwise they will need thorough scrubbing in hot water before paring or grating. For an elegant presentation, lemons can be segmented like oranges or grapefruit.
In the kitchen
Lemons have several important supporting roles in cookery. One of their earliest tasks was as a garnish for fish, just as they are used today. Lemons are also an essential accompaniment to deep-fried foods. They act as a flavour enhancer for other ingredients, bringing a sweet acidic element to marinades, salad dressing and sauces, and will halt discolouration of cut raw ingredients such as pears and fennel. Their pectin content makes them an essential component of jams and jellies. Salt-pickled lemons are a staple flavouring of North African cooking; lemons can also be preserved in vinegar or olive oil. Some Mediterranean regions use lemon chopped raw in salads.
The fruit also takes a central role in recipes such as lemon curd, tarte citron and avgolémono, where its combination with eggs gives a balance of richness and acidity. Lemon zest is an important ingredient in its own right and contains essential oils that lend a dish perfume as well as flavour.
Amalfi lemons, which come from the Amalfi coast in Italy, are very highly regarded.