Averrhoa bilimbi

Averrhoa bilimbi

The bilimbi or cucumber tree, tree sorrel (Averrhoa bilimbi L. 1753) is an arboreal species belonging to the Oxalidaceae family.

Systematics –
From a systematic point of view it belongs to:
Eukaryota domain,
Kingdom Plantae,
Magnoliophyta division,
Class Magnoliopsida,
Geraniales Order,
Oxalidaceae family,
Genus Averrhoa,
Species A. bilimbi.
The terms are synonyms:
– Averrhoa abtusangulata Stokes;
– Averrhoa obtusangula Stokes.

Etymology –
The term Averrhoa was attributed in honor of Averroes, the Latinized name by which the Arab philosopher, jurist, doctor and astronomer of Spain Abū l-Walīd Muḥammad ibn Rushd (1126-1198) is known in the West.
The specific epithet bilimbi appears to be a transliteration or corruption of the original Malay or Indonesian term “belimbing” which is used to refer to this plant.

Geographic Distribution and Habitat –
Averrhoa bilimbi is probably a plant native to the Moluccas; in Indonesia, the species is now cultivated and is found throughout Indonesia, East Timor, the Philippines, Sri Lanka, Bangladesh, the Maldives, Myanmar (Burma), and Malaysia. It is also common in other Southeast Asian countries. In India, where it is usually found in gardens, bilimbi has spread to warmer regions of the country. It is also found in the coastal regions of southern India.
Outside of Asia, the tree is grown in Zanzibar. In 1793, bilimbi was introduced to Jamaica from Timor and after several years was grown throughout Central and South America where it is known as mimbro. In Suriname this fruit is known as lange birambi. Introduced to Queensland in the late 19th century, it has been grown commercially in the region ever since. In Guyana it is called Sourie, One finger, Bilimbi and Kamranga.
Its natural habitat is that of primary and secondary lowland forests, usually along rivers, where it thrives in tropical and subtropical climates, at altitudes up to 1,200 metres. It prefers regions with high humidity and regular rainfall. The plant is often found growing in back gardens, small orchards, and along roadsides in its native regions. It can adapt to various soil types, but grows best in well-draining, fertile soils with a pH that ranges from slightly acidic to neutral.

Description –
Averrhoa bilimbi is a tree that reaches 5 to 10 m in height.
It has a short trunk that rapidly divides into numerous branches and can be up to 30 cm in diameter.
The leaves are 3-6 cm long and alternate, imparipinnate, and grouped at the ends of the branches. These are dense near the apex of the branches, 15–48 cm long; leaflets 7–25, oblong to elliptical, 2.5–9.2 cm long and 1–2.6 cm broad, apex acute to acuminate, often mucronate, base rounded, tomentose, petioles fleshy, 1–2 mm long ; petioles 3.5-10 cm long.
The inflorescences are borne in cymes with 1–24 flowers; the sepals are ovate to elliptical in shape, 3-5 mm long, acute, mucronate; the petals are 9-12 mm long and 2-4 mm wide, of a purplish-red color, then becoming dark purple-black; fertile stamens 10, 5 long and 5 short, free or connate at the base, glabrous; the ovary is oblong, carpels 1-7-ovulate.
The fruit is 4 to 10 cm long, and can be helical, ovoid or almost cylindrical and with five faces, like the fruit of the carambola, but in a much less marked way. It is bright light green, slightly translucent and turns yellowish when ripe. The skin of the fruit is very thin and the pulp is very acidic.
Inside the fruit there are 6 or 7 small seeds in the shape of a flattened disc.

Cultivation –
Averrhoa bilimbi is an essentially tropical tree, less resistant to cold than carambola, which grows better in rich and well-drained soils (but it also tolerates limestone and sand). It prefers rains evenly distributed throughout the year, but with a dry season of 2 to 3 months. Thus, the species is not found in, for example, the wetter part of Malaysia.
In its natural habitat it can also be found at altitudes of up to 1,200 metres. It grows best in areas where annual daytime temperatures are between 23-30°C, but can tolerate 10-36°C.
Mature plants can be killed by temperatures of -3°C or lower, but young shoots are severely damaged at -1°C.
It prefers an average annual rainfall between 1,200 and 2,300 mm, but tolerates between 700 and 4,000 mm.
They are also quite drought tolerant plants and do well when there is a 2 – 3 month dry season.
When choosing the area where to grow them, remember that they prefer a position in full sun, growing rather slowly in shady or semi-shady situations.
The plant thrives well on any type of soil as long as it is well drained, however, to obtain the best productions, it should be cultivated in deep, fertile, sandy or clayey soils with a lot of organic substance; it also grows better in a position sheltered from strong winds.
From a soil point of view, it prefers a soil pH in the range of 5.5 – 6.5, tolerating 5 – 8.3.
Grafted trees can start producing when they are 2 – 3 years old and a single tree can often produce many hundreds of fruit. Yields of 50 to 150 pounds per tree have been reported.
Flowers and fruit are produced throughout most of the year, although there are normally one or two pronounced harvest seasons, each lasting about 2 months.
Flowering and fruiting occur mostly during the driest part of the year.
It is a tree that lives very long.
As far as propagation is concerned, it can be propagated from seed, although this is generally not recommended because when it is to be grown as a fruit crop there is great genetic variability between seedlings.
Propagation methods also include layering, grafting and root cutting since it has been observed that the severed roots of trees are capable of producing adventitious growths from which independent plants are generated.

Customs and Traditions –
Averrhoa bilimbi is a plant cultivated since ancient times in tropical Southeast Asia, even if the exact place of origin is not known.
This plant is known by various names, including: bilimbi, bilimbi-tree, cucumber-tree, sour finger carambola, tree-sorrel (English); san lian, san nien (Chinese); carambolier bilimbi, cornichon des Indes, zibeline (French); bilimbi (Hindi); belimbing asam, belimbing besu, belimbing wuluh (Malay); limâo-de-Caiena (Portuguese); bilimbi, grosella china, limón chino, mimbro, pepino de Indias, tiriguro, vinagrillo (Spanish); bilimbibaum, gurkenbaum (German).
In the past, the fruits were used to whiten skin spots, remove rust stains from clothes, clean knife blades and polish brass objects. Leaves and fruits are used in traditional medicine for various pathologies, but they must be used with great caution due to the side effects due to the high oxalic acid content.
In Indonesia, the A. bilimbi, known locally as belimbing wuluh, is often used to give a tart or acidic flavor to food, as a substitute for tamarind or tomato; in fact its fruits are more acidic than those of Averrhoa carambola and contain vitamin C.
In the northwestern province of Aceh, the fruit is preserved by salting and drying it in the sun to make asam sunti, a cooking condiment for preparing a variety of Acehnese dishes. It is a key ingredient in many Indonesian dishes such as sambal believing wuluh.
In the Philippines, where it is commonly called kamias and ibâ, they are commonly found in backyards. The fruits are eaten raw or dipped in rock salt. It can be curried or added as an acidifying agent for common Filipino dishes such as sinigang, pinangat and paksiw. Here too it is dried in the sun for conservation. It is also used to make mixed salad with tomatoes, chopped onions with soy sauce as a dressing.
Raw bilimbi is prepared as a condiment and served with rice and beans in Costa Rica.
In the Far East, where the tree originated, it is sometimes added to curries.
In Malaysia and the Philippines, bilimbi or kamias is made into a rather sweet and sour jam, with a flavor profile similar to plums or plums.
In Kerala and Bhatkal, India, it is used to make fish pickles and curries, especially with sardines, while in Karnataka, Maharashtra and Goa, the fruit is commonly eaten raw with salt and spices. In Guyana and Mauritius, it is made into achar/pickle.
In the Maldives, where it is known as bilimagu, it is pickled with aromatic spices and eaten with rice and the local Garudhiya (fish soup). It is also used in various local Maldivian dishes such as Boakibaa and Mashuni as an acidifying agent.
In Seychelles, it is often used as an ingredient to give a piquant flavor to many Seychellois Creole dishes, especially fish dishes. It is often used in grilled fish and also (almost always) in a shark meat dish, called satini reken. It is also cooked with onion, tomato and chili peppers to make a sauce. They are sometimes seasoned with salt for use when out of season.
Bilimbi juice (with a pH of about 4.47) is made into a refreshing drink. It can replace mango in the preparation of chutney. Also, the fruit can be preserved by pickling, which reduces its acidity.
However, it should be remembered that the fruit contains high levels of oxalate which, in excess consumption, can cause acute renal failure due to tubular necrosis.
This pathology, caused by oxalate, has been recorded in several people who drank the concentrated juice for continuous days as a treatment for high cholesterol.
In Philippine folk medicine, the leaves are used to make a paste used to treat itching, swelling, rheumatism, mumps, or skin rashes. In other places they are used to treat bites from poisonous animals. An infusion of leaves is used as a postpartum tonic, while an infusion made from its flowers is used to treat candidiasis, colds and coughs. Malays use fresh or fermented bilimbi leaves to treat venereal disease. In French Guiana, an extract prepared from the fruit is used to treat inflammation. There is no scientific evidence to confirm the effectiveness of these uses.
In some villages of Thiruvananthapuram district of India, the bilimbi fruit was used in local medicine to control obesity. This has led to studies on its antihyperlipidemic properties.
Among other uses it should be remembered that in Malaysia, very acidic bilimbi are used to clean the blades of kris.
In the Philippines, it is often used in rural areas as an alternative stain remover.
In the Addu region of the Maldives, the flowers of the bilimbi plant were reportedly commonly used as a fabric dye in the 20th century.
Additionally, the raw juice of the fruit effectively removes stains or stains on clothing, rust stains on brass, and stubborn food particles on enamelware.
The fruits are used as a mordant in the preparation of an orange dye for silk fabrics.
A purple dye from the petals is used as an indicator in chemistry.
The wood, which is white, soft but strong, uniformly grained, weighs 35 pounds/cubic foot. However it is rarely available in sufficient size to be used for joinery.
Wood is used as fuel.

Method of Preparation –
The fruit of Averrhoa bilimbi is eaten raw, cooked or pickled. It can be used to make juices, accompany dishes or as a condiment. In the Philippines it is eaten raw, with salt. It is used as an ingredient in the cuisine of many tropical Asian countries where it is used to flavor dishes such as curry or sinigang. The intensely acidic flavor sometimes makes it a substitute for tamarind pulp.
In Costa Rica, stewed bilimbi is eaten with rice and beans. In Aceh cuisine it is used fresh or dried.
In general, however, it is a multipurpose plant that provides food, medicine and a wide range of other products.
Of the edible uses, as mentioned, the fruit is occasionally eaten raw with salt or thinly sliced and added to salads, although most people find it too acidic and use it in curries, sauces, etc. instead.
When ripe it is crunchy, juicy, acidic, and contains few flattened seeds.
The fruit is widely used as an acidifying agent for many native dishes; moreover it can also be made into candy or made into chutneys, toppings and pickles.
Even the flowers are made into preserves.
In the medicinal field, the leaves are used which can be used to treat syphilis if taken internally, fresh or fermented. Typically a preparation involves three leaves being placed in water and the liquid being drunk daily as a remedy for high blood pressure.
When applied externally as a paste or poultice, the leaves prevent itching.
A decoction of the leaves is used to treat inflammation of the rectum, and the paste is applied for mumps, rheumatism and pimples.
An infusion of the flowers is used for the cough.
The fruit is an astringent, stomachic and coolant and its juice is made into syrup as a refreshing drink to reduce fever.
It is antiscorbutic and is used in some mild cases of bleeding from the intestines as well as from the stomach and internal bleeding. It is also used to treat beriberi, biliousness and cough.
To control diarrhea, one or two pickled fruits are eaten.
A rotten fruit is rubbed into the peel to cure fungal diseases.

Guido Bissanti

Sources
– Acta Plantarum – Flora of the Italian Regions.
– Wikipedia, the free encyclopedia.
– GBIF, the Global Biodiversity Information Facility.
– Useful Tropical Plants Database.
– Conti F., Abbate G., Alessandrini A., Blasi C. (ed.), 2005. An annotated checklist of the Italian vascular flora, Palombi Editore.
– Pignatti S., 1982. Flora of Italy, Edagricole, Bologna.
– Treben M., 2000. Health from the Lord’s Pharmacy, Advice and experiences with medicinal herbs, Ennsthaler Editore.

Photo source:
– https://inaturalist-open-data.s3.amazonaws.com/photos/109636837/original.jpg

Attention: The pharmaceutical applications and alimurgical uses are indicated for informational purposes only, they do not in any way represent a medical prescription; we therefore decline all responsibility for their use for curative, aesthetic or food purposes.