''Citrus hystrix'', called the kaffir lime, Thai lime or makrut lime, (, ) is a

citrus fruit ''Citrus'' is a genus of flowering plant, flowering trees and shrubs in the family Rutaceae. Plants in the genus produce citrus fruits, including important crops such as Orange (fruit), oranges, Mandarin orange, mandarins, lemons, grapefruits, ...

native to

tropical The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's ax ...

Southeast Asia Southeast Asia is the geographical United Nations geoscheme for Asia#South-eastern Asia, southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of the Mainland Au ...

. Its fruit and leaves are used in

Southeast Asian cuisine This is a list of Asian cuisines, by region. A cuisine is a characteristic style of cooking practices and traditions, usually associated with a specific culture or region. Asia, being the largest, most populous and culturally diverse continent, ...

, and its

essential oil An essential oil is a concentrated hydrophobic liquid containing volatile (easily evaporated at normal temperatures) chemical compounds from plants. Essential oils are also known as volatile oils, ethereal oils, aetheroleum, or simply as the ...

is used in perfumery. Its rind and crushed leaves emit an intense citrus fragrance.

Names

The most likely

etymology Etymology ( ) is the study of the origin and evolution of words—including their constituent units of sound and meaning—across time. In the 21st century a subfield within linguistics, etymology has become a more rigorously scientific study. ...

is through the Kaffirs, an ethnic group in

Sri Lanka Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka, also known historically as Ceylon, is an island country in South Asia. It lies in the Indian Ocean, southwest of the Bay of Bengal, separated from the Indian subcontinent, ...

partly descended from enslaved

Bantu Bantu may refer to: *Bantu languages, constitute the largest sub-branch of the Niger–Congo languages *Bantu peoples, over 400 peoples of Africa speaking a Bantu language * Bantu knots, a type of African hairstyle *Black Association for National ...

. The earliest known reference, under the alternative spelling "caffre" is in the 1888 book ''The Cultivated Oranges, Lemons Etc. of India and Ceylon'' by Emanuel Bonavia, who notes, "The plantation

coolie Coolie (also spelled koelie, kouli, khuli, khulie, kuli, cooli, cooly, or quli) is a pejorative term used for low-wage labourers, typically those of Indian people, Indian or Chinese descent. The word ''coolie'' was first used in the 16th cent ...

s also smear it over their feet and legs, to keep off land

leech Leeches are segmented parasitism, parasitic or Predation, predatory worms that comprise the Class (biology), subclass Hirudinea within the phylum Annelida. They are closely related to the Oligochaeta, oligochaetes, which include the earthwor ...

es; and therefore in Ceylon ri Lankait has also got the name of ''Kudalu dchi'', or Leech Lime. Europeans call it Caffre Lime." Similarly, H.F. MacMillan's 1910 book ''A Handbook of Tropical Gardening and Planting'' notes, "The 'Kaffir Lime' in Ceylon." Another proposed etymology is directly by Indian Muslims of the imported fruit from the non-Muslim lands to the east to "convey otherness and exotic provenance." Claims that the name of the fruit derives directly from the

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

n ethnic slur " kaffir" ''(see "South Africa" below)'' are not well supported. ''C. hystrix'' is known by various names in its native areas: * in Javanese and in Malay (respectively into

Indonesian Indonesian is anything of, from, or related to Indonesia, an archipelagic country in Southeast Asia. It may refer to: * Indonesians, citizens of Indonesia ** Native Indonesians, diverse groups of local inhabitants of the archipelago ** Indonesian ...

and Malaysian) both meaning "warty/rough-skinned lime" due to the fruit's bumpy texture. * ( "arrow-leaf lime") in

Chinese Chinese may refer to: * Something related to China * Chinese people, people identified with China, through nationality, citizenship, and/or ethnicity **Han Chinese, East Asian ethnic group native to China. **'' Zhonghua minzu'', the supra-ethnic ...

. * or in the Philippines. The city of

Cabuyao Cabuyao (), officially the City of Cabuyao (), is a component city in the province of Laguna, Philippines. According to the 2020 census, it has a population of 355,330 people. It used to be known as the "richest municipality in the Philipp ...

in Laguna is named after the fruit. *''Kolumichai'', கொலுமிச்சை in

Kongu Tamil Kongu Tamil or Kovai Tamil (also called Kongalam, Kongu Pechu, Coimbatore Tamil) is the dialect of Tamil language that is spoken by the people in Kongu Nadu, which is the western region of Tamil Nadu. It is originally known as "Kangee"` or "Kong ...

* or (, ) in Thailand (a name also used for the

bergamot orange ''Citrus bergamia'', the bergamot orange (pronounced ), is a fragrant citrus fruit the size of an orange, with a yellow or green colour similar to a lime, depending on ripeness. Genetic research into the ancestral origins of extant citrus cul ...

). * (, ) in Laos. * or in

Vietnam Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...

. * in

Réunion Réunion (; ; ; known as before 1848) is an island in the Indian Ocean that is an overseas departments and regions of France, overseas department and region of France. Part of the Mascarene Islands, it is located approximately east of the isl ...

Island The micrantha, a similar citrus fruit native to the Philippines that is ancestral to several hybrid limes, such as the

Key lime The Key lime or acid lime (''Citrus'' × ''aurantiifolia'' or ''C. aurantifolia'') is a citrus hybrid (''kaffir lime, C. hystrix'' × ''citron, C. medica'') native to tropical Southeast Asia. It has a spherical fruit, in diameter. The Key lime ...

and

Persian lime Persian lime (''Citrus'' × ''latifolia''), also known by other common names such as seedless lime, Bearss lime and Tahiti lime, is a citrus fruit species of hybrid origin, known only in cultivation. The Persian lime is a triploid cross betwe ...

, may represent the same species as ''C. hystrix'', but the genomic characterization of the kaffir lime has not been performed in sufficient detail to allow a definitive conclusion.

South Africa

In South Africa, the Arabic ''kafir'' was adopted by White colonialists as " kaffir," an ethnic slur for black African people. Consequently, some authors favour switching from "kaffir lime" to "makrut lime," a less well-known name, while in South Africa, it is usually referred to as "Thai lime".

Description

''C. hystrix'' is a thorny shrub or small tree, tall, with aromatic and distinctively shaped "double" leaves. These hourglass-shaped leaves comprise the leaf blade plus a flattened, leaf-like stalk (botanically, a winged

petiole Petiole may refer to: *Petiole (botany), the stalk of a leaf, attaching the blade to the stem *Petiole (insect anatomy) In entomology, petiole is the technical term for the narrow waist of some hymenopteran insects, especially ants, bees, and ...

). The fruit is rough and green and ripens to yellow; it is distinguished by its bumpy exterior and small size, approximately wide. The fruits have thick skins ( pericarps) and taste very acidic and slightly bitter. Flowers can have four to five petals that are white in color and are fragrant.

History

Pierre Sonnerat Pierre Sonnerat (18 August 1748 – 31 March 1814) was a French naturalist, colonial administrator, writer and explorer. He described numerous species of plants and animals on his travels and is honoured in the genus ''Sonneratia'' and in other ...

(1748–1814) collected specimens of it in 1771–72, and it appears in Lamarck's Encyclopédie Méthodique (1796). Makrut lime appears in texts under the name of kaffir lime in 1868, in Ceylon, where rubbing the juice onto legs and socks prevents leech bites. This could be a possible origin of the name leech lime.

Uses

Culinary

''C. hystrix'' leaves are used in Southeast Asian cuisines such as

, Laotian, Cambodian, and Thai. The leaves are the most frequently used part of the plant, fresh, dried, or frozen. The leaves are widely used in

Thai cuisine Thai cuisine (, , ) is the national cuisine of Thailand. Thai cooking places emphasis on lightly prepared dishes with aromatics and spicy heat. The Australian chef David Thompson (chef), David Thompson, an expert on Thai food, observes that ...

(for dishes such as tom yum) and

Cambodian cuisine Cambodian cuisine is the national cuisine of Cambodia. It reflects the varied culinary traditions of different ethnic groups in Cambodia, central of which is Khmer cuisine (, ), the nearly-two-thousand-year-old culinary tradition of the Khmer pe ...

(for the base paste " krueng"). The leaves are used in

Vietnamese cuisine Vietnamese cuisine encompasses the foods and beverages originated from Vietnam. Meals feature a combination of five fundamental tastes (): sweet, salty, bitter, sour, and Piquant, spicy. The distinctive nature of each dish reflects one or more ...

to add fragrance to chicken dishes and to decrease the pungent odor when steaming snails. Also, in Vietnamese villages that harvest

silkworms ''Bombyx mori'', commonly known as the domestic silk moth, is a moth species belonging to the family Bombycidae. It is the closest relative of '' Bombyx mandarina'', the wild silk moth. Silkworms are the larvae of silk moths. The silkworm is of ...

, the silkworms in the

pupa A pupa (; : pupae) is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their life cycle, the stages th ...

stage are

stir fried Stir frying ( zh, c= 炒, p=chǎo, w=ch'ao3, cy=cháau) is a cooking technique in which ingredients are fried in a small amount of very hot oil while being stirred or tossed in a wok. The technique originated in China and in recent centuries ...

with the kaffir lime leaves. The leaves are used in

Indonesian cuisine Indonesian cuisine is a collection of various regional culinary traditions by various ethnic groups that formed in the archipelagic nation of Indonesia. There are a wide variety of recipes and cuisines in part because Indonesia is composed ...

(especially

Balinese cuisine Balinese cuisine is a cuisine tradition of Balinese people from the volcanic island of Bali. Using a variety of spices, blended with the fresh vegetables, meat and fish. Part of Indonesian cuisine, it demonstrates indigenous traditions, as well a ...

and

Javanese cuisine Javanese cuisine () is the cuisine of Javanese people, a major Native Indonesian, ethnic group in Indonesia in the provinces of Central Java, Yogyakarta, and East Java. Definition Javanese cuisine refers exclusively to the cuisine of Javan ...

) for foods such as

soto ayam Soto ayam is a traditional Indonesian dish with ingredients such as chicken, ''lontong'', noodles, and rice vermicelli. Soto ayam is also popular in Singapore, Malaysia and Suriname, where it is made with slightly different ingredients and known ...

and are used along with Indonesian bay leaf for chicken and fish. They are also found in Malaysian and Burmese cuisines. The rind (peel) is commonly used in Lao and

Thai curry Thai curry (, ) is a dish in Thai cuisine made from curry paste, coconut milk or water, meat, seafood, vegetables or fruit, and herbs. Curries in Thailand mainly differ from the Indian subcontinent in their use of ingredients such as fresh rhizo ...

paste, adding an aromatic, astringent flavor. The zest of the fruit, referred to as combava, is used in

creole cuisine Creole cuisine (; ; ) is a cuisine style born in colonial times, from the fusion between African, European and pre-Columbian traditions. ''Creole'' is a term that refers to those of European origin who were born in the New World and have adap ...

to impart flavor in infused rums and rougails in

Mauritius Mauritius, officially the Republic of Mauritius, is an island country in the Indian Ocean, about off the southeastern coast of East Africa, east of Madagascar. It includes the main island (also called Mauritius), as well as Rodrigues, Ag ...

, and

Madagascar Madagascar, officially the Republic of Madagascar, is an island country that includes the island of Madagascar and numerous smaller peripheral islands. Lying off the southeastern coast of Africa, it is the world's List of islands by area, f ...

. In Cambodia, the entire fruit is crystallized/candied for eating.Dy Phon Pauline, 2000, ''Plants Used In Cambodia'', printed by Imprimerie Olympic, Phnom Penh

Medicinal

The juice and rinds of the peel are used in traditional medicine in some Asian countries; the fruit's juice is often used in shampoo and is believed to kill head lice.

Other uses

The juice is used as a cleanser for clothing and hair in Thailand and occasionally in Cambodia. Lustral water mixed with slices of the fruit is used in religious ceremonies in Cambodia. Makrut lime oil is used as raw material in many fields, including pharmaceutical, agronomic, food, sanitary, cosmetic, and perfume industries. It is also used extensively in aromatherapy and as an essential ingredient in various cosmetic and beauty products. File:Fish stuffed with Thai herbs.jpg, Striped snakehead fish stuffed with ''C. hystrix'' and

lemongrass ''Cymbopogon'', also known as lemongrass, barbed wire grass, silky heads, oily heads, Cochin grass, Malabar grass, citronella grass or fever grass, is a genus of Asian, African, Australian, and tropical island plants in the grass family. Some ...

in preparation for steaming File:Flickr - cyclonebill - Tom yam.jpg, ''C. hystrix'' leaves floating in tom yum File:Citrus hystrix DC. (AM AK305877-3).jpg, Fruit longitudinal section File:Combava Rind Madagascar.jpg, Dried fruit rinds File:Combava Powder Madagascar.jpg, Powdered fruit rind, used in

Malagasy cuisine Malagasy may refer to: *Someone or something from Madagascar * Malagasy people *Malagasy language Malagasy ( ; ; Sorabe: ) is an Austronesian languages, Austronesian language and dialect continuum spoken in Madagascar. The standard variety, c ...

File:Phanaeng kai.jpg, Cut leaf strips on chicken phanaeng File:2022.08-516-248ap1 Large bags with Citrus hystrix leaves for sale in Phou Puy Wholesale Vegetable Market in Battambang, Cambodia sat27aug2022-1516h.jpg, ''C. hystrix'' leaves for sale in Phou Puy Wholesale Vegetable Market in

Battambang Battambang (, Romanization of Khmer#UNGEGN, UNGEGN: ) is the capital of Battambang province and the List of cities and towns in Cambodia, third largest city in Cambodia. The city is situated on the Sangkae River, which winds its way through t ...

, Cambodia (August 2022)

Cultivation

''C. hystrix'' is grown worldwide in suitable climates as a garden shrub for home fruit production. It is well suited to

container garden Container gardening or pot gardening/farming is the practice of growing plants, including edible plants, exclusively in containers instead of planting them in the ground. A container in gardening is a small, enclosed and usually portable object ...

s and for large garden pots on

patio A patio (, ; ) is an outdoor space generally used for dining or recreation that adjoins a structure and is typically paved. In Australia, the term is expanded to include roofed structures such as a veranda, which provides protection from sun ...

s, terraces, and in conservatories.

Main constituents

The compound responsible for the characteristic aroma was identified as (–)-(''S'')-citronellal, which is contained in the leaf oil up to 80 percent; minor components include

citronellol Citronellol, or dihydrogeraniol, is a natural acyclic monoterpenoid. Both enantiomers occur in nature. (+)-Citronellol, which is found in citronella oils, including '' Cymbopogon nardus'' (50%), is the more common isomer. (−)-Citronellol is ...

(10 percent),

nerol Nerol is a monoterpenoid alcohol found in many essential oils such as lemongrass and hops. It was originally isolated from neroli oil, hence its name. This colourless liquid is used in perfumery. Like geraniol, nerol has a sweet rose odor but it ...

and

limonene Limonene () is a colorless liquid aliphatic hydrocarbon classified as a cyclic monoterpene, and is the major component in the essential oil of citrus fruit peels. The (+)-isomer, occurring more commonly in nature as the fragrance of oranges, ...

. From a stereochemical point of view, it is remarkable that makrut lime leaves contain only the (''S'')

stereoisomer In stereochemistry, stereoisomerism, or spatial isomerism, is a form of isomerism in which molecules have the same molecular formula and sequence of bonded atoms (constitution), but differ in the three-dimensional orientations of their atoms in ...

of citronellal, whereas its

enantiomer In chemistry, an enantiomer (Help:IPA/English, /ɪˈnænti.əmər, ɛ-, -oʊ-/ Help:Pronunciation respelling key, ''ih-NAN-tee-ə-mər''), also known as an optical isomer, antipode, or optical antipode, is one of a pair of molecular entities whi ...

, (+)-(''R'')-citronellal is found in both

lemon balm Lemon balm (''Melissa officinalis'') is a perennial herbaceous plant in the mint family. It has lemon-scented leaves, white or pale pink flowers, and contains essential oils and compounds like geranial and neral. It grows to a maximum height o ...

and (to a lesser degree)

lemon grass ''Cymbopogon'', also known as lemongrass, barbed wire grass, silky heads, oily heads, Cochin grass, Malabar grass, citronella grass or fever grass, is a genus of Asian, African, Australian, and tropical island plants in the grass family. Some ...

, (however, citronellal is only a trace component in the latter's essential oil). Makrut lime fruit peel contains an essential oil comparable to lime fruit peel oil; its main components are limonene and β-pinene.

Toxicity

''C. hystrix'' contains significant quantities of

furanocoumarins The furanocoumarins, or furocoumarins, are a class of organic chemical compounds produced by a variety of plants. Most of the plant species found to contain furanocoumarins belong to a handful of plant families. The families Apiaceae and Rutacea ...

, in both the peel and the pulp. Furanocoumarins are known to cause

phytophotodermatitis Phytophotodermatitis, also known as berloque dermatitis,, margarita photodermatitis,, lime disease or lime phytodermatitis is a cutaneous phototoxic inflammatory reaction resulting from contact with a light-sensitizing botanical agent (such as ...

, a potentially severe skin inflammation. Cases of phytophotodermatitis induced by external use of ''C. hystrix'' have been reported.

References

{{Taxonbar, from=Q465934 Southeast Asian cuisine Limes (fruit) Citrus

Citrus ''Citrus'' is a genus of flowering trees and shrubs in the family Rutaceae. Plants in the genus produce citrus fruits, including important crops such as oranges, mandarins, lemons, grapefruits, pomelos, and limes. ''Citrus'' is nativ ...

Herbs Lao cuisine Filipino cuisine Spices Thai cuisine Austronesian agriculture