The lemon is a small evergreen tree (Citrus limon) originally native to Asia, and is also the name of the tree's oval yellow fruit. The fruit is used for culinary and nonculinary purposes throughout the world – primarily for its juice, though the pulp and rind (zest) are also used, mainly in cooking and baking. Lemon juice is about 5% (approximately 0.3 mole per liter) citric acid, which gives lemons a tart taste, and a pH of 2 to 3. This makes lemon juice an inexpensive, readily available acid for use in educational science experiments. Because of the tart flavor, many lemon-flavored drinks and candies are available, including lemonade.

History

The exact origin of the lemon has remained a mystery, though it is widely presumed that lemons first grew in India, northern Burma, and China. In South and South East Asia, it was known for its antiseptic properties and it was used as an antidote for various poisons. It was later introduced to Persia and then to Iraq and Egypt around AD 700. The lemon was first recorded in literature in a tenth century Arabic treatise on farming, and was also used as an ornamental plant in early Islamic gardens. It was distributed widely throughout the Arab world and the Mediterranean region between AD 1000 and AD 1150.

Lemons entered Europe (near southern Italy) no later than the first century AD, during the time of Ancient Rome. However, they were not widely cultivated. The first real lemon cultivation in Europe began in Genoa in the middle of the fifteenth century. It was later introduced to the Americas in 1493 when Christopher Columbus brought lemon seeds to Hispaniola along his voyages. Spanish conquest throughout the New World helped spread lemon seeds. It was mainly used as ornament and medicine. In 1700s and late 1800s, lemons were increasingly planted in Florida and California when lemons began to be used in cooking and flavoring.

In 1747, James Lind's experiments on seamen suffering from scurvy involved adding Vitamin C to their diets through lemon juice. Case 3: Naval Medicine: The Fight Against Scurvy @ King's College at London. Information on this site is based from: James Lind. A treatise on the scurvy. Second edition. London: printed for A. Millar, 1757. [St. Thomas's Historical Collection 28.b.9].

Etymology

Lemon : Its Origin is in 1350–1400; 1905–10. According to www.dictionary.com: Although we know neither where the lemon was first grown nor when it first came to Europe, we know from its name that it came to us from the Middle East because we can trace its etymological path. One of the earliest occurrences of our word is found in a Middle English customs document of 1420-1421. The Middle English word limon goes back to Old French limon, showing that yet another delicacy passed into England through France. The Old French word probably came from Italian limone, another step on the route that leads back to the Arabic word laymūn or līmūn, which comes from the Persian word līmūn.

Varieties

• Meyer lemon - Is a cross between a lemon and possibly an orange or a mandarin, was named for Frank N. Meyer who first discovered it in 1908. Thin-skinned and slightly less acidic than the Lisbon and Eureka lemons, Meyer lemons require more care when shipping and are not widely grown on a commercial basis.
• Lisbon - A good quality bitter lemon with high juice and acid levels. The fruits of Eureka and Lisbon are very similar. Vigorous and productive, trees are very thorny particularly when young.
• Eureka
• Verna - A Spanish variety of unknown origin.
• Bush Lemon Tree - Naturalized lemon grown wild in subtropical Australia. They are very hardy, have a thick skin with a true lemon flavour. Grows to about 4m in a sunny position. The skin makes a good zest for cooking.
• Villafranca
• Lemonade
• West Indian or Mexican or Key
• Tahitian or Persian

Culinary uses

Lemons are used to make lemonade, and as a garnish for drinks. Lemon zest has many uses. Many mixed drinks, soft drinks, iced tea, and water are often served with a wedge or slice of lemon in the glass or on the rim. The average lemon contains approximately 3 tablespoons of juice. Allowing lemons to come to room temperature before squeezing (or heating briefly in a microwave) makes the juice easier to extract. Lemons left unrefrigerated for long periods of time are susceptible to mold.

Fish are marinated in lemon juice to neutralize the odor. The acid neutralizes the amines in fish by converting them into nonvolatile ammonium salts.

Lemon juice, alone or in combination with other ingredients, is used to marinate meat before cooking: the acid provided by the juice partially hydrolyzes the tough collagen fibers in the meat (tenderizing the meat), though the juice does not have any antibiotic effects.

Lemons, alone or with oranges, are used to make marmalade. The grated rind of the lemon, called lemon zest, is used to add flavor to baked goods, puddings, rice and other dishes. Pickled lemons are a Moroccan delicacy. A liqueur called limoncello, typical of southern Italy, is made from lemon rind.

When lemon juice is sprinkled on certain foods that tend to oxidize and turn brown after being sliced, such as apples, bananas and avocados, the acid acts as a short-term preservative by denaturing the enzymes that cause browning and degradation.

Non-culinary uses

• Citric acid - Lemons were the primary commercial source of this substance prior to the development of fermentation-based processes.
• Lemon battery - A popular science experiment in schools involves attaching electrodes to a lemon and using it as a battery to produce electricity. Although very low power, several lemons used in this way can power a small digital watch. These experiments also work with other fruits and vegetables.
• Sanitary kitchen deodorizer - deodorize, remove grease, bleach stain, and disinfect; when mixed with baking soda, lemon can remove stains from plastic food storage containers.
• Insecticide - The d-limonene in lemon oil is used as a non-toxic insecticide treatment. See orange oil.
• Antibacterial uses because it has a low pH
• Wood treatment - the traditional lemon oil used on the unsealed rosewood fingerboards of guitars and other stringed instruments is not made from lemons. It's a different product altogether, made from mineral oil and a solvent, usually naphtha, and got its name from its color and tart smell, and should not be confused with the corrosive oil of lemons.
• A halved lemon is used as a finger moistener for those counting large amounts of bills such as tellers and cashiers.
• Aromatherapy - In one of the most comprehensive scientific investigations done yet, researchers at Ohio State University reveal that lemon oil aroma does not influence the human immune system but may enhance mood.
• A halved lemon dipped in salt or baking powder can be used to brighten copper cookware. The acid cuts through the tarnish and the abrasives assist the cleaning.
• Lemon juice may also be used lighten hair color.

Lemon alternatives

Several other plants have a similar taste to lemons. In recent times, the Australian bush food lemon myrtle has become a popular alternative to lemons. The crushed and dried leaves and edible essential oils have a strong, sweet lemon taste but contain no citric acid. Lemon myrtle is popular in foods that curdle with lemon juice, such as cheesecake and ice cream. Limes are often used instead of lemons.

Many other plants are noted to have a lemon-like taste or scent. Among them are Cymbopogon (lemon grass), lemon balm, lemon thyme, lemon verbena, scented geranium, certain cultivars of basil, and certain cultivars of mint.

Production

India tops the production list with ~16% of the world's overall lemon and lime output followed by Mexico(~14.5%), Argentina(~10%), Brazil(~8%) and Spain(~7%).

Top Ten Lemons and Limes Producers — 2007
Country	Production (Tonnes)
	2,060,000F
	1,880,000F
	1,260,000F
	1,060,000F
	880,000F
	745,100F
	722,000
	706,652
	615,000F
	546,584
	13,032,388F
No symbol = official figure, F = FAO estimate, A = Aggregate(may include official, semi-official or estimates); Source: Food And Agricultural Organization of United Nations: Economic And Social Department: The Statistical Devision

References

1. Wright, A. Clifford. History of Lemonade, CliffordAWright.com
2. The origins, limmi.it.
3. Morton, J. 1987. Lemon. p. 160–168. Fruits of warm climates. (Julia F. Morton, Miami, FL.) @ Purdue University
4. http://www.australiancitrusgrowers.com/aspdev/resources/documents/Verna9-02.pdf
5. http://9am.ten.com.au/lemon-trees.htm
6. http://www.energyquest.ca.gov/projects/lemon.html California Energy Commission
7. 6 ingredients for a green, clean home, Shine. Retrieved on April 24, 2008.
8. 9 Ohio State University Research, March 3, 2008 Study is published in the March 2008 issue of the journal Psychoneuroendocrinology
9. Lemon Myrtle

External links

• (Purdue University) Morton, Julia F. 1987. "Lemon". pp. 160–168, in Fruits of warm climates. (Julia F. Morton, Miami)
• PlantFiles: Citrus x meyeri 'Meyer'