Lemon

Thelemon(Citrus×limon) is aspeciesof smallevergreentree in theCitrusgenus of theflowering plantfamilyRutaceae. The lemon is ahybridof thecitronand thebitter orange. Its origins are uncertain, but some evidence suggests lemons originated during the 1st millennium BC in what is now northeasternIndia.
The yellowfruitof the lemon tree is used throughout the world, primarily for itsjuice. The pulp andrindare used in cooking and baking. The juice of the lemon is about 5–6%citric acid, giving it a sour taste. This makes it a key ingredient indrinksand foods such aslemonadeandlemon meringue pie.
In 2022, world production was 22 milliontonnes, led by India with 18% of the total.
The lemon tree produces a pointed oval yellowfruit. Botanically this is ahesperidium, a modifiedberrywith a tough, leathery rind. The rind is divided into an outer colored layer orzest, which is aromatic withessential oils, and an inner layer of white spongy pith. Inside are multiplecarpelsarranged as radial segments. The seeds develop inside the carpels. The space inside each segment is aloculefilled withjuice vesicles.
Lemons contain manyphytochemicals, includingpolyphenols,terpenes, andtannins.Their juice contains slightly morecitric acidthanlimejuice (about 47 g/L), nearly twice as much asgrapefruitjuice, and about five times as much asorangejuice.
The lemon, like many other cultivatedCitrusspecies, is ahybrid, in its case of thecitronand thebitter orange.
Lemons were most likely first grown in northeast India.The origin of the wordlemonmay be Middle Eastern.The word draws from the Old Frenchlimon, then Italianlimone, from the Arabicليمونlaymūnorlīmūn, and from thePersianلیموlīmūn, a generic term forcitrusfruit, which is a cognate of Sanskrit (nimbū, 'lime').
Lemons enteredEuropenear southernItalyno later than the second century AD, during the time ofAncient Rome.They were later introduced toPersiaand then toIraqandEgyptaround 700 AD.The lemon was first recorded in literature in a 10th-centuryArabictreatise on farming; it was used as an ornamental plant in earlyIslamic gardens.It was distributed widely throughout the Arab world and theMediterranean regionin theArab Agricultural Revolutionbetween 1000 and 1150.A section on lemon and lime tree cultivation inAndalusia,Spain, was included inIbn al-'Awwam's 12th-century agricultural work,Kitāb al-Filāha("Book on Agriculture").The first substantial cultivation of lemons in Europe began inGenoain the middle of the 15th century. It was introduced to theAmericasin 1493, whenChristopher Columbusbrought lemon seeds toHispaniolaon his voyages. Spanish conquest throughout theNew Worldhelped spread lemon seeds, part of theColumbian exchangeof plants between theOldand New Worlds. It was mainly used as an ornamental plant and for medicine.In the 19th century, lemons were increasingly planted inFloridaandCalifornia.In 1747, the English physicianJames Lind's experiments on seamen suffering fromscurvyinvolved adding lemon juice to their diets, thoughvitamin Cwas not yet known as an important dietary ingredient.
Lemons need a minimum temperature of around 7 °C (45 °F), so they are not hardy year-round in temperate climates, but become hardier as they mature.Citrus require minimal pruning by trimming overcrowded branches, with the tallest branch cut back to encourage bushy growth.Throughout summer, pinching back tips of the most vigorous growth assures more abundant canopy development. As mature plants may produce unwanted, fast-growing shoots (called "water shoots"), these are removed from the main branches at the bottom or middle of the plant.There is reputed merit in the tradition ofurinatingnear a lemon tree.
In cultivation in theUK, the cultivars "Meyer"and "Variegata"have gained theRoyal Horticultural Society'sAward of Garden Merit(confirmed 2017).
In 2022, world production of lemons (combined withlimesfor reporting) was 22 milliontonnesled by India with 18% of the total. Mexico and China were major secondary producers (table).
The 'Bonnie Brae' is oblong, smooth, thin-skinned, and seedless.These are mostly grown inSan Diego County, US.
The 'Eureka' grows year-round and abundantly. This is the common supermarket lemon, also known as "Four Seasons" (Quatre Saisons) because of its ability to produce fruit and flowers together throughout the year. This variety is also available as a plant for domestic customers.There is also apink-fleshed Eureka lemonwith a green and yellowvariegatedouter skin.
The Lisbon lemon is very similar to the Eureka and is the other common supermarket lemon. It is smoother than the Eureka, has thinner skin, and has fewer or no seeds. It generally produces more juice than the Eureka.
The 'Femminello St. Teresa', or 'Sorrento' originates in Italy. This fruit'szestis high in lemon oils. It is the variety traditionally used in the making oflimoncello.
The 'Yen Ben' is an Australasian cultivar.
Lemon is a rich source ofvitamin C, providing 64% of theDaily Valuein a 100 g reference amount (table). Otheressential nutrientsare low in content.
Lemon juice and rind are used in a wide variety of foods and drinks, the juice for its sour taste, from its content of 5–6%citric acid.The whole lemon is used to makemarmalade,lemon curdandlemon liqueurssuch asLimoncello.Lemon slices and lemon rind are used as agarnishfor food and drinks. Lemonzest, the grated outer rind of the fruit, is used to add flavor to baked goods.The juice is used to makelemonadeand somecocktails.
It is used inmarinadesfor fish, where its acid neutralizesaminesin fish.In meat, the acid partiallyhydrolyzestough collagen fibers,tenderizingit.In theUnited Kingdom, lemon juice is frequently added topancakeseaten to celebrateShrove Tuesday.Lemon juice is used as a short-termpreservativeon certain foods that tend to oxidize and turn brown after being sliced (enzymatic browning), such asapples,bananas, andavocados: its acidity suppressesoxidationbypolyphenol oxidaseenzymes.
Lemon peel is used in the manufacture ofpectin, a gelling agent and stabilizer in food and other products.In Mediterranean countries includingMorocco, lemons are preserved in jars or barrels of salt. The salt penetrates the peel and rind, softening them, and curing them so that they last almost indefinitely.
Lemon oil is extracted from oil-containing cells in the skin. A machine breaks up the cells and uses a water spray to flush off the oil. The oil–water mixture is then filtered and separated bycentrifugation.
The leaves of the lemon tree are used to make a tea and for preparing cooked meats andseafoods.
Lemons were the primary commercial source ofcitric acidbefore the development offermentation-based processes.Lemon oil is used inaromatherapy. Lemon oil aroma does not influence the humanimmune system,but may contribute to relaxation.An educational science experiment involves attachingelectrodesto a lemon and using it as abatteryto produce electricity. Although very low power, severallemon batteriescan power a small digital watch.Lemon juice forms a simpleinvisible ink, developed by heat.Lemon juice is sometimes used to increase theblondecolor of hair, acting as a natural highlight after the moistened hair is exposed to sunlight. This works because citric acid acts as bleach.
Lemons appear in paintings, pop art, and novels.A wall painting in thetomb of Nakhtin 15th century BC Egypt depicts a woman in a festival, holding a lemon. In the 17th century,Giovanna Garzonipainted aStill Life with Bowl of Citrons, the fruits still attached to leafy flowering twigs, with a wasp on one of the fruits. TheimpressionistEdouard Manetdepicted a lemon on a pewter plate. In modern art,Arshile GorkypaintedStill Life with Lemonsin the 1930s.
InIndia, a lemon may be ritually encircled around a person in the belief that it repels negative energies.It is a common practice for Hindu owners of a new car to drive over four lemons, one under each wheel, crushing them during their first drive. This is believed to protect the driver from accidents.Hindu deitiesare sometimes depicted with lemons in theiriconography, representing the attribute of wealth or abundance.
In 20th century Americanself-improvementculture,Dale Carnegieadvised readers "If You Have a Lemon, Make a Lemonade", meaning to make the best of what you have. In the 21st century, a defective machine such as a car is called a lemon.