The Durian is a fruit widely known and revered in southeast Asia as the "king of fruits". It belongs to the genus Durio and the Malvaceae family (although some taxonomists place Durio in a distinct family, Durionaceae). The durian has a distinctive smell and formidable thorn-covered husk. The fruit is about 30 centimetres (12 in) long and 15 centimetres (6 in) in diameter. It typically weighs one to three kilograms (2 to 7 lb). Its shape ranges from oblong to round while the colour of its husk is green to brown. The flesh of the durian ranges from pale-yellow to red, depending on the species.
The edible flesh has a distinctive smell that is strong and penetrating even when the husk is intact. Some people regard the durian as fragrant; others find the aroma overpowering and offensive. The smell evokes reactions from deep appreciation to intense disgust. The odour has led to the fruit's banishment from certain hotels and public transportation in southeast Asia.
The durian is native to Malaysia, Indonesia, Brunei and Thailand. There is some debate as to whether the durian is native to the Philippines, or was introduced. It has been known to the Western world for about 600 years. The 19th-century British naturalist Alfred Russel Wallace famously described its flesh as "a rich custard highly flavoured with almonds". The flesh can be consumed at various stages of ripeness, and is used to flavour a wide variety of savoury and sweet edibles in Southeast Asian cuisines. There are 30 recognised Durio species, at least nine of which produce edible fruit. Durio zibethinus is the only species available in the international market. There are hundreds of durian cultivars; many consumers express preferences for specific cultivars, which fetch higher prices in the market.
The island of Borneo has the most diverse species of durians. Among the edible species of durians available here include D. zibethinus, D. dulcis, D. graveolens, D. kutejensis, D. oxleyanus and D. testudinarum are sold in local markets. In Brunei, D. zibethinus is not grown because consumers prefer other species such as D. graveolens, D. kutejensis and D. oxleyanus. These species are commonly distributed in Brunei, and together with other species like D. testudinarum and D. dulcis, represent rich genetic diversity.
In Peninsular Malaysia and Singapore, the season for durians is typically from June to August, which coincides with that of the mangosteen. Prices of durians are relatively high as compared with other fruits. For example, in Singapore, the strong demand for high quality cultivars such as the D24, Sultan, and Mao Shan Wang has resulted in typical retail prices of between S$8 to S$15 (US$5 to US$10) per kilogram of whole fruit. With an average weight of about 1.5 kilograms (3.3 lb), a durian fruit would therefore cost about S$12 to S$22 (US$8 to US$15). The edible portion of the fruit, known as the aril and usually referred to as the "flesh" or "pulp", only accounts for about 15-30% of the mass of the entire fruit. Many consumers in Singapore are nevertheless quite willing to spend up to around S$75 (US$50) in a single purchase of about half a dozen of the favoured fruit to be shared by family members.
Durian trees are relatively large, growing to 25 - 50 metres (80 - 165 ft) in height depending on the species. The leaves are evergreen, elliptic to oblong and 10 - 18 centimetres (4 - 7 in) long. The flowers are produced in three to thirty clusters together on large branches and directly on the trunk with each flower having a calyx (sepals) and five (rarely four or six) petals. Durian trees have one or two flowering and fruiting periods per year, though the timing varies depending on the species, cultivars, and localities. A typical durian tree can bear fruit after four or five years. The durian fruit can hang from any branch and matures roughly three months after pollination. The fruit can grow up to 30 centimetres (12 in) long and 15 centimetres (6 in) in diameter, and typically weighs one to three kilograms (2 to 7 lb). Its shape ranges from oblong to round, the colour of its husk green to brown, and its flesh pale-yellow to red, depending on the species. Among the thirty known species of Durio, nine of them have been identified as producing edible fruits: D. dulcis, , D. grandiflorus, D. graveolens, D. kutejensis, D. lowianus, D. macrantha, D. oxleyanus and D. testudinarum. However, there are many species for which the fruit has never been collected or properly examined, so other species with edible fruit may exist.
The name durian comes from the Malay word duri (thorn) together with the suffix -an (for building a noun in Malay). D. zibethinus is the only species commercially cultivated on a large scale and available outside of its native region. Since this species is open-pollinated, it shows considerable diversity in fruit colour and odour, size of flesh and seed, and tree phenology. In the species name, zibethinus refers to the Indian civet, Viverra zibetha. There is disagreement regarding whether this name, bestowed by Linnaeus, refers to civets being so fond of the durian that the fruit was used as bait to entrap them, or to the durian smelling like the civet.
Durian flowers are large and feathery with copious nectar, and give off a heavy, sour and buttery odour. These features are typical of flowers pollinated by certain species of bats that eat nectar and pollen. According to research conducted in Malaysia in the 1970s, durians were pollinated almost exclusively by cave fruit bats (Eonycteris spelaea). However, a 1996 study indicated two species, D. grandiflorus and D. oblongus, were pollinated by spiderhunters (Nectariniidae) and another species, D. kutejensis, was pollinated by giant honey bees and birds as well as bats.
Over the centuries, numerous durian cultivars propagated by vegetative clones have arisen in southeast Asia. They used to be grown with mixed results from seeds of trees bearing superior quality fruit, but are now propagated by layering, marcotting, or more commonly, by grafting, including bud, veneer, wedge, whip or U-grafting onto seedlings of randomly selected rootstocks. Different cultivars can be distinguished to some extent by variations in the fruit shape, such as the shape of the spines. Durian consumers express preferences for specific cultivars, which fetch higher prices in the market.
Most cultivars have a common name and a code number starting with "D". For example, some popular clones are Kop (D99), Chanee (D123), Berserah or Green Durian or Tuan Mek Hijau (D145), Kan Yao (D158), Mon Thong (D159), Kradum Thong and with no common name, D24 and D169. Each cultivar has a distinct taste and odour. More than 200 cultivars of D. zibethinus exist in Thailand. Chanee is the most preferred rootstock due to its resistance to infection by Phytophthora palmivora. Among all the cultivars in Thailand, only four are currently in large-scale commercial cultivation: Chanee, Kradum Thong, Mon Thong, and Kan Yao. There are more than 100 registered cultivars in Malaysia and many superior cultivars have been identified through competitions held at the annual Malaysian Agriculture, Horticulture and Agrotourism Show. In Vietnam, the same process has been done through competitions held by the Southern Fruit Research Institute.
In recent times, Songpol Somsri, a Thai government scientist, crossbred more than ninety varieties of durian to create Chantaburi No. 1, a cultivar without the characteristic odour, which is awaiting final approval from the local Ministry of Agriculture. Another hybrid, Chantaburi No. 3, develops the odour about three days after the fruit is picked, which enables an odourless transport yet satisfies consumers who prefer the pungent odour.
Durian is used to flavour a wide variety of sweet edibles such as traditional Malay candy, ice kacang, dodol, rose biscuits, and, with a touch of modern innovation, ice cream, milkshakes, mooncakes, Yule logs and cappuccino. Pulut Durian is glutinous rice steamed with coconut milk and served with ripened durian. In Sabah, red durian is fried with onions and chilli and served as a side dish. Red-fleshed durian is traditionally added to sayur, an Indonesian soup made from fresh water fish. Ikan brengkes is fish cooked in a durian-based sauce, traditional in Sumatra. Tempoyak refers to fermented durian, usually made from lower quality durian that is unsuitable for direct consumption. Tempoyak can be eaten either cooked or uncooked, is normally eaten with rice, and can also be used for making curry. Sambal Tempoyak is a Sumatran dish made from the fermented durian fruit, coconut milk, and a collection of spicy ingredients known as sambal.
In Thailand, blocks of durian paste are sold in the markets, though much of the paste is adulterated with pumpkin. Unripe durians may be cooked as a vegetable, except in the Philippines, where all uses are sweet rather than savoury. Malaysians make both sugared and salted preserves from durian. When durian is minced with salt, onions and vinegar, it is called boder. The durian seeds, which are the size of chestnuts, can be eaten whether they are boiled, roasted or fried in coconut oil, with a texture that is similar to taro or yam, but stickier. In Java, the seeds are sliced thin and cooked with sugar as a confection. Uncooked durian seeds are toxic due to cyclopropene fatty acids and should not be ingested. Young leaves and shoots of the durian are occasionally cooked as greens. Sometimes the ash of the burned rind is added to special cakes. The petals of durian flowers are eaten in the Batak provinces of Indonesia, while in the Moluccas islands the husk of the durian fruit is used as fuel to smoke fish. The nectar and pollen of the durian flower that honeybees collect is an important honey source, but the characteristics of the honey are unknown.
Durian http://commons.wikimedia.org/wiki/File:Durian_rack_in_Kuala_Lumpur.jpeg Jack Merridew
Pack of durian showing segments and stone http://commons.wikimedia.org/wiki/File:Durianpack01.JPG Markalexander100
Durian tree and durians http://commons.wikimedia.org/wiki/File:Durian_in_tree.jpg AmonHeijne