Kaffir lime


Citrus hystrix, called the kaffir lime, makrut lime, Thai lime or Mauritius papeda, is a citrus fruit native to tropical Southeast Asia and southern China.
Its fruit and leaves are used in Southeast Asian cuisine and its essential oil is used in perfumery. Its rind and crushed leaves emit an intense citrus fragrance.

Names

The etymology of the name "kaffir lime" is uncertain.
C. hystrix is known by various names in its native areas:
The micrantha, a similar citrus fruit native to the Philippines that is ancestral to several hybrid limes, such as the Key lime and Persian lime, may represent the same species as C. hystrix, but genomic characterization of the kaffir lime has not been performed in sufficient detail to allow a definitive conclusion.

Naming controversy

In South Africa, "kaffir" is an ethnic slur for black African people. Consequently, some authors favour switching from "kaffir lime" to "makrut lime", a name less well established in English, while in South Africa it is usually referred to as "Thai lime".

Description

C. hystrix is a thorny bush, tall, with aromatic and distinctively shaped "double" leaves. These hourglass-shaped leaves comprise the leaf blade plus a flattened, leaf-like stalk. The fruit is rough and green, and ripens to yellow; it is distinguished by its bumpy exterior and its small size, approximately wide.

Uses

Cuisine

The leaves are the most frequently used part of the plant, fresh, dried, or frozen. The leaves are widely used in Thai and Lao cuisine and Cambodian cuisine. The leaves are used in Vietnamese cuisine to add fragrance to chicken dishes and to decrease the pungent odor when steaming snails. The leaves are used in Indonesian cuisine for foods such as soto ayam and are used along with Indonesian bay leaf for chicken and fish. They are also found in Malaysian and Burmese cuisines. It is used widely in Bengali and South Indian cuisine.
The rind is commonly used in Lao and Thai curry paste, adding an aromatic, astringent flavor. The zest of the fruit, referred to as combava, is used in creole cuisine to impart flavor in infused rums and rougails in Mauritius, Réunion, and Madagascar. In Cambodia, the entire fruit is crystallized/candied for eating.

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 finds use as a cleanser for clothing and hair in Thailand and very occasionally in Cambodia. Lustral water mixed with slices of the fruit is used in religious ceremonies in Cambodia.

Cultivation

C. hystrix is grown worldwide in suitable climates as a garden shrub for home fruit production. It is well suited to container gardens and for large garden pots on patios, terraces, and in conservatories.

Main constituents

The compound responsible for the characteristic aroma was identified as --citronellal, which is contained in the leaf oil up to 80 percent; minor components include citronellol, nerol and limonene.
From a stereochemical point of view, it is remarkable that kaffir lime leaves contain only the stereoisomer of citronellal, whereas its enantiomer, --citronellal, is found in both lemon balm and lemon grass,.
Kaffir 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, in both the peel and the pulp. Furanocoumarins are known to cause phytophotodermatitis, a potentially severe skin inflammation. One case of phytophotodermatitis induced by C. hystrix has been reported.