Durian

Durian
	Durian tree ( Durio zibethinus )
Systematics
	Eurosiden II
Order :	Mallow-like (Malvales)
Family :	Mallow family (Malvaceae)
Subfamily :	Helicteroideae
Genre :	Durian trees ( Durio )
Type :	Durian
Scientific name
	Durio zibethinus
	L. ex Murray

The durian tree ( Durio zibethinus , Thai ทุเรียน , RTGS transcription Thurian ; Malay Pokok Durian Kampung ), also known as the civet tree, is a species of the mallow family (Malvaceae). It is originally native to Indonesia and Malaysia . Today it is cultivated throughout Southeast Asia and some other tropical areas. The fruit durian , also called civet fruit , is used as a fruit . There are different opinions about their taste and smell. Some consumers value them greatly because of their complex taste, while others are repulsed by their taste and smell.

description

Appearance and leaf

The durian tree grows as an evergreen tree that can reach heights of up to 40 meters. The best growth rates are achieved on alluvial or clay soils that are well supplied with water. In the primary forest , durian trees do not appear to form a stand, but are usually only found widely scattered (on average about 1 tree on 4 hectares). Typical features are the protruding, steep roots , the slender, high trunk and the high, often almost horizontal, strong branches. Trees cultivated in plantations remain significantly smaller (maximum 10 meters) and develop a crown that almost attaches to the base of the trunk.

The alternate and two lines are arranged on the branches leaves are divided in leaf blade and leaf stem. The petiole is 1.5 to 3 cm long. The leathery, simple leaf blade is 6 to 25 cm long and 2.5 to 9 cm wide with entire margins and pinnate veins with a rounded or blunt blade base. The upper side of the leaf is glossy, the underside of the leaf is golden yellow or silver and mostly covered with scales. The 1.5 to 2 cm long stipules fall off early.

Illustration of the durian tree ( Durio zibethinus )

Inflorescence and flower

Three to thirty flowers stand together in zymous inflorescences , which are located on leafless nodes (nodes) on the branches. The flower stalk is 2 to 4 cm long.

The decrepit, fleshy calyx is closed when budded and opens with irregular fissures or is two- to three-lobed. The blooms , which smell unpleasantly of sour milk, are hermaphroditic and open for less than 24 hours in the late afternoon. They are only capable of being pollinated between around 5 p.m. and 6 a.m. The flowers are visited by various types of insects (honey bees, beetles and flies), but they are only involved in pollination to a lesser extent. The main part of the pollination is the nocturnal long- nosed lesser long- tongue bat ( Eonycterus spelaea ), which is generally regarded as an important pollinator of many forest tree species in Southeast Asia.

The three to five leathery sepals are bell-shaped fused with an expanded calyx base and four to six calyx tips. The 2.25 to 3 cm high calyx is densely covered with scales on the outside and densely hairy on the inside. There are none, four to five or more free petals . The yellow-white petals are elongated-spatulate with a length of 3.5 to 5 cm and curved back at the upper end. There are many fertile stamens present. In four or five bundles there are 4 to 18 stamens together, which are fused together over a length of a quarter to half. Three to six carpels are three to a top continuous to sechskammerigen ovary grown. Each ovary chamber contains some ovules . The stylus is narrow with a heady scar.

genetics

In November 2017, a team of authors from Singapore described the decoding of the complete genome of Durio zibethinus ( Musang King variety ). The genome contained around 45,000 genes ( calculated bioinformatically ), roughly twice as many as the human genome, and comprised 738 Mbp . The genetic analysis also provided new insights into the origin of the smell and taste of the durian fruit. Several metabolic pathways that are responsible for the production of sulfur-containing chemical compounds ( thiols , disulfides , trisulfides ), which are responsible for the onion-like odor, or esters , which cause the sweet, fruity odor, have been identified.

Some flavors of the durian fruit
( S ) -2-methylbutyric acid ethyl ester (fruity)
( E ) -ethyl cinnamon ester (honey smell)
1-propanethiol (rotten)
3-methyl-2-butene-1-thiol (skunk odor)
1-ethylsulfanyl-ethanethiol (roasted onion odor )

The durian fruit

Fruit, aril and seeds

The fruits are ripe for harvest about 90 to 130 days (depending on the cultivar ) after pollination of the flowers. Harvesting the fruits is laborious and has not yet been mechanized. Harvesters have to climb the tree and check the degree of ripeness of fruits based on certain criteria (smell, color, knocking noise, etc.). The ripe fruits are then picked and lowered into a basket. Contact with the ground should be avoided in order to avoid easier spoilage by microorganisms. Fruits that spontaneously fall from the tree have a significantly shorter shelf life.

The ripe fruit is coconut - up to the size of a head and weighs 2 to 4 kilograms. The fruit peel is light yellow to greenish-yellow or gray-green when ripe and has many hard, wood-like spines about one centimeter long . The ellipsoidal, loculicidal capsule fruit with a length of 15 to 30 cm and a diameter of 13 to 15 cm is divided by relatively thick walls into three to five or sometimes six completely separate chambers. Each fruit chamber contains up to six seeds, which are covered by a white to yellowish, thick, fleshy, greasy, strongly smelling seed coat ( arillus ), which is also known as the pulp . The consistency of the pulp is comparable to that of fibrous pudding. The seeds contain endosperm .

In its natural environment, the fruit is consumed by many forest-dwelling animal species, including elephants , orangutans , rats, etc. The animals ensure that the seeds are spread.

Taste and smell

The flesh is sweet and has an incomparable taste. Since the aromatic smell, which is dependent on the variety and maturity, disappears unusually slowly and is perceived by some as unpleasant, it has a polarizing effect. The taste is described as reminiscent of walnut and vanilla, but with a strong fruity top note and a clear onion flavor. The smell of the durian fruit is described as leek and cheese-like. It is mainly caused by dithio hemiacetals and other sulfur-containing compounds . A total of around two hundred compounds have been found so far, which contribute differently to the odor. The compound 1-ethylsulfanyl-ethanethiol is of particular interest. Their smell is reminiscent of fried onions. The substance is known from, for example, the leek . But it has not been observed in any other fruit than that of the durian tree.

Consumption and Processing

There are tastings of different varieties and origins, comparable to wine tastings in Europe. These durian tastings and the durian festivals in the growing regions, which take place every year, attract lovers of this exotic species from all over the world, which some call the “king of fruits”. In the main growing countries such as Malaysia or Thailand there are many different varieties that are highly valued and achieve appropriate prices. The main trading center for durian fruits is Singapore .

In Europe, fresh durian fruits are most likely to be found in Asian shops in metropolises with a large Asian population, such as London; otherwise they are rarely offered fresh in Europe, mostly only in large delicatessen departments. In Asian shops, however, you can often find frozen whole fruit, durian segments (seeds with pulp) and frozen pulp.

For consumption, the whole fruit is opened at the seams and the seeds covered by the pulp are removed from the individual chambers; the pulp is separated from the seed core. The fruits should be intact when purchased; Overripe durian fruits open by themselves, which affects the taste and which attracts insects even with an extreme fragrance. In Singapore, after consuming durian, mangosteen fruits are often consumed as they are supposed to help digest the somewhat difficult to digest durian.

Durian fruits in a market.
Opening a durian fruit
Comparison of two varieties. The fruit peel and the fruit chambers that contain the aril are clearly visible.
Durian segments are also sold in portions (sometimes frozen).

In addition to being eaten raw , durian fruits are used to make jams , cakes , ice cream , fruit juice and curry dishes . The seeds are also prepared in the growing countries, e.g. B. thinly cut and roasted as a kind of chips.

A warning is given against consuming alcohol with durian, as this can lead to cramping abdominal pain. Medical examinations on this question have so far not produced any clear results, but suggest that no harmful interaction is to be expected, the symptoms are temporary.

Medically, the reason for alcohol intolerance is the inhibition of the enzyme aldehyde dehydrogenase (ALDH), which is necessary for the breakdown of alcohol (inhibition of enzyme activity by 81.5%). The drinking alcohol ( ethanol ) is first broken down into toxic acetaldehyde . This requires alcohol dehydrogenases (ADH) . In the second step, the acetaldehyde is oxidized to acetic acid by ALDH . If the enzyme ALDH is inhibited, e.g. B. by consuming durian or even more strongly from some mushrooms, these same toxins are not or only delayed degraded, which can explain the corresponding complaints. In the case of the durian fruit, sulfur compounds are responsible for the inhibition.

No durians , prohibition sign on the Singapore Metro

Wood

The wood of the durian tree has an average density (r ₁₅ ) of 0.69 g / cm³ and is counted among the lighter hardwoods of Southeast Asia. The wood is moderately to good physically resilient, but not very durable and not very resistant to wood pests. It is easy to work with and is used to make door and window frames, floors, etc., among other things. Among other things, it is also used to make toys.

Use in the healing arts

In folk medicine , leaves, fruits, bark and roots of the durian tree are used for fever and hepatitis , the fruits as a tonic and sexual enhancer ( aphrodisiac ).

Durian fruit in the hotel and on public transport

Due to the unpleasant smell, it is usually not permitted to take durian fruits into hotels or airplanes. Once the smell sets in, it's difficult to get rid of. That is why it is common in hotels to have to pay for the room for another week if the durian ban is violated. In Singapore, it is also prohibited to carry durians on the MRT ( subway ), which is indicated by signs; however, no penalty is given. In Malaysia, it is also prohibited to carry this fruit on trains and airplanes.

In November 2018, several tons of durian stowed in the hold of a Sriwijaya Air plane caused tumult among the angry passengers in Jakarta, Indonesia . The plane was only able to take off one hour late after the fruit had been unloaded again.

Evacuations over durian fruits

In May 2019, a University of Canberra library had to be evacuated due to an alleged gas leak and searched by the fire department. The reason was a left durian fruit.

In June 2020, a package with four durian fruits in Schweinfurt caused a large-scale operation by the police, several fire departments and rescue services. A Deutsche Post building was completely cleared. Twelve employees had to receive medical care because of nausea, six of them were hospitalized as a precaution. Foreign media also reported on the incident.

Home and growing areas

Main Producer (1996)
rank	country	Annual production (t)
1	Thailand Thailand	950,000
2	Malaysia Malaysia	400,000
3	Indonesia Indonesia	200,000

Original area of origin of the durian cultivation introduced later

Habit of the durian tree in a plantation

The natural home of Durio zibethinus is probably the Malay Peninsula , as well as the islands of Borneo and Sumatra .

Today elite forms are grown in many areas of the tropics, especially on the Indian subcontinent , in Indochina and Malesia . The durian tree can be found, for example, in Thailand , Vietnam in the Philippines , but also in the tropical countries of Africa and even in Queensland in Australia . The main producing countries are Thailand, followed by Malaysia and Indonesia.

Most durians are grown for local fresh consumption. Thailand is the largest exporter. About 10% (80,000 t) of the Thai cultivation was exported in 1996. The main customer countries were Taiwan , neighboring Malaysia, the People's Republic of China , the United States , Hong Kong and Singapore. Fresh durians were mainly exported to neighboring countries and frozen fruits to the United States.

Naming

The name of the prickly durian fruit is derived from the Malay word duri , which means “thorn” or “thorn”.

Taxonomy

The first publication of Durio zibethinus was made in 1774 by Carl Linnaeus in Johan Andreas Murray (ed.): Systema Vegetabilium Secundum Classes Ordines genera species cum Characteribus et differentiis. Editio decima tertia… Gottingae. P. 581; Murray writes in the foreword that all names come from Linnaeus. A homonym is Durio zibethinus Moon (published in Alexander Moon: A Catalog of the Indigenous and Exotic Plants Growing in Ceylon 1824, p. 56.)

swell

Durio zibethinus Murray, Malvaceae at Pacific Island Ecosystems at Risk (PIER). (Section description)

literature

Brigitte Kranz: The big book of fruits: exotic and native species . Südwest-Verlag, Munich 1981, ISBN 3-517-00732-3 .
Nadja Biedinger: The world of tropical plants . DuMont, Cologne 2000, ISBN 3-7701-5294-8 .
Roland Hanewald: Edible Fruits of Asia . Reise Know-How, Bielefeld, ISBN 3-89416-771-8 .
Rolf Blancke: Color atlas of exotic fruits: fruits and vegetables of the tropics and subtropics . Ulmer, Stuttgart 2000, ISBN 3-8001-3520-5 .
Wilhelm Lötschert, Gerhard Beese: Plants of the tropics: 323 ornamental and useful plants . 4th revised edition. BLV, Munich 1992, ISBN 3-405-14448-5 . (Identification book, which helps to explain the exotic fruits on the local market with good photos.)
Christa Weil: Cuisine Fatale: a potpourri from international extreme cuisine . Ullstein, Berlin 2007, ISBN 978-3-548-36923-5 . (Book about curious dishes with information on the cultural background and with a special focus on the peculiarities of trying to eat them.)
Michael J. Brown: Durio - A Bibliographic Review. International Plant Genetic Resources Institute, 1997, ISBN 92-9043-318-3 (online)

Web links

Commons : Durian tree ( Durio zibethinus ) - collection of images, videos and audio files

Food and Agriculture Organization of the United Nations = FAO: Durio zibethinus - data sheet at Ecocrop (online).
Durio zibethinus - Datasheet at MH Porcher among others: Searchable World Wide Web Multilingual Multiscript Plant Name Database. (MMPND).
Crop Info and How-to Guide in Growing Durian .
General information about durian. ( Memento from February 10, 2008 in the Internet Archive )
Wilfried Stevens: The Thai national fruit Durian. (No longer available online.) In: Thaipage.ch. August 14, 2013, archived from the original on January 8, 2018 .; accessed on November 16, 2019
Stink on board. - Outrage about stink fruit flying with you, NZZ, June 22, 2012

Individual evidence

↑ Durian. tropenkost.de, accessed on February 1, 2016 .

↑ Thomas Fuller, Poypiti Amatatham, Natalia V. Osipova: Travel: The King of Fruits. The New York Times, December 3, 2013, accessed February 1, 2016 .

↑ Katy Salter: Durian, the world's smelliest fruit, goes on sale in Britain. The Guardian, February 3, 2014, accessed February 1, 2016 .

↑ ^a ^b ^c ^d Walter Kollert: Durio zibethinus . In: Schütt, Weisgerber, Schuck, Lang, Stimm, Roloff (ed.): Trees of the tropics . Nikol Verlagsgesellschaft, Hamburg 2006, ISBN 978-3-933203-79-3 , p. 291-296 .

↑ Bin Tean Teh, Kevin Lim, Chern Han Yong, Cedric Chuan Young Ng, Sushma Ramesh Rao, Vikneswari Rajasegaran, Weng Khong Lim, Choon Kiat Ong, Ki Chan, Vincent Kin Yuen Cheng, Poh Sheng Soh, Sanjay Swarup, Steven G Rozen , Niranjan Nagarajan, Patrick Tan: The draft genome of tropical fruit durian (Durio zibethinus) . In: Nature Genetics . tape 49 , 2017, p. 1633–1641 , doi : 10.1038 / ng . 3972 (English).

^ Durian Harvesting. The Philippine Council for Agriculture, Forestry and Natural Resources Research and Development (PCARRD), accessed March 24, 2018 .

↑ Griebel, C .: For the microscopic detection of durian and nillu onion (Salpamisri) , Journal for Food Analysis and Research A, 1928 , 55 (5) , 453–459. doi: 10.1007 / BF01660443

↑ Baldry, J. et al .: Volatile flavoring constituents of durian , Phytochemistry , 1972 , 11 , 2081-2087. doi: 10.1016 / S0031-9422 (00) 90176-6

↑ Volker Mrasek : The secret of the stink fruit - German researchers investigate the Asian durian , Deutschlandfunk " Forschung aktuell " from February 11, 2013

↑ Li, Jia-Xiao. et al .: Characterization of the Major Odor-Active Compounds in Thai Durian (Durio zibethinus L. `Monthong`) by Aroma Extract Dilution Analysis and Headspace Gas Chromatography-Olfactometry . In: Journal of agricultural and food chemistry . tape 60 , no. 45 , 2012, p. 11253-11262 , doi : 10.1021 / jf303881k .

↑ Swift, R. & Davidson, D. (1998): Alcohol Hangover: Mechanism and Mediators . Alcohol Health & Research World. 22 (1): 54-60. [1]

↑ John S. Maninang, Ma.Concepcion C. Lizada, Hiroshi Gemma (2009) Inhibition of aldehyde dehydrogenase enzymes by Durian (Durio zibethinus Murray) Fruit Extract. Food Chemistry 117 (2): 352-355. doi : 10.1016 / j.foodchem. 2009.03.106

↑ ^a ^b ^c Durio zibethinus in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland.

↑ Barbara Simonsohn: Healing power from the tropics. Integral, 2009, ISBN 978-3-641-01991-4 ( limited preview in Google Book Search).

↑ Nicola Smith: Indonesian passenger plane grounded after two tonnes of pungent durian fruit triggers revolt on www.telegraph.co.uk , November 7, 2018

↑ Indonesian plane grounded after passengers complain about stinky durian on www.bbc.com , November 7, 2018

↑ Michael McGowan: Library stink: smell of durian prompts evacuation at University of Canberra at www.guardian.com , May 13, 2019

↑ Thai stink fruit triggers large-scale operation in Schweinfurt on www.br.de , June 20, 2020

↑ Rebecca Ratcliffe: Smelly durian fruit forces evacuation of Bavarian post office on www.guardian.com , June 23, 2020

↑ Large-scale operation because of stinky fruit! Six postmen in the hospital on heute.at , June 20, 2020

^ ^A ^b Production and Marketing Situation: World durian situation. (No longer available online.) Archived from the original on April 3, 2016 ; accessed on January 30, 2016 .

^ Durio zibethinus. (PDF) worldagroforestry.org, accessed January 30, 2016 .

↑ DURIAN FRUITING SEASONS WORLDWIDE. The Archives of the Rare Fruit Council of Australia, accessed January 30, 2016 .

^ Tropical Fruit Global Information System. Accessed January 30, 2016 .

↑ Michael J. Brown: Durio - A Bibliographic Review . International Plant Genetic Resources Institute, 1997, ISBN 92-9043-318-3 , p. 2.

^ IPNI on the work of the first publication.

^ Durio zibethinus at Tropicos.org. Missouri Botanical Garden, St. Louis

[1] Durian. tropenkost.de, accessed on February 1, 2016 .

[2] Thomas Fuller, Poypiti Amatatham, Natalia V. Osipova: Travel: The King of Fruits. The New York Times, December 3, 2013, accessed February 1, 2016 .

[3] Katy Salter: Durian, the world's smelliest fruit, goes on sale in Britain. The Guardian, February 3, 2014, accessed February 1, 2016 .

[tropen-4] Walter Kollert: Durio zibethinus . In: Schütt, Weisgerber, Schuck, Lang, Stimm, Roloff (ed.): Trees of the tropics . Nikol Verlagsgesellschaft, Hamburg 2006, ISBN 978-3-933203-79-3 , p. 291-296 .