Dragon fruit


Dragon fruit (Hylocereus undatus), a tropical fruit popular in Southeast Asia, belongs to the climbing cacti (Cactaceae) family. Vietnam is the main commercial producer of dragon fruits in this region. The fruit, apart from being refreshing and tasty, has loads of vitamin C and is said to aid digestion.

Origin and distribution
The fruit is native to Central America. It is known as Pitahaya in Mexico and as Pitaya roja in Central America and northern South America. Pitahaya is the Spanish name for fruiting vines of Central America. The fruit was introduced in Vietnam by the French over a hundred years ago. According to some, the French took the fruit from Nicaragua and Colombia while others said they brought it from Guyana (South America) in 1870 as an ornamental plant. For its large attractive flowers which bloom only at night, the flamboyant plant is also known as "moonflower" or "lady of the night".

When the Vietnamese discovered the plant's tasty fruit, they cultivated it for food, just as the Mexicans did. The Vietnamese now regard this fruit as indigenous, especially the white flesh variety, Hylocereus undatus, or called Blue Dragon or thanh long by the Vietnamese Only of late was the fruit grown in Vietnam on a large-scale as a commercial crop. As one of Vietnam's most profitable crops, it is exported to markets all over the Southeast Asia. The commercialisation of the crop is also catching up in Thailand, New Zealand, Australia and Hawaii.

The plant gets its genus name Hylocerus from the word cerus derived from the Latin word cera, meaning "wax" or "torch-like".

Description
The plant is a climbing cactus vine that grows well in dry areas. Because of its epiphytic nature, it grows best in soil with a high level of organic materials. The flowers are white and large, measuring 30 cm long or more. They are ornate and produce a sweet fragrance when in bloom. The flowers bloom for one night only. Pitahaya plants can have between four to six fruiting cycles in one year. It can be propagated by seed or by stem cuttings.

The dragon fruit has a dramatic appearance, bright pink or yellow skinned (from Columbia) with green coloured spine-like scales. The scales turn yellow as the fruit ripens while the skin peels easily. The fruit is oval shaped, elliptical or pear-shaped. Inside, the flesh has subtly flavoured sweet taste or sometimes slightly sourish. The flesh is either white or red with black seeds dotted all over. The seeds resemble sesame seeds and taste like cactus seeds. It imparts a crunchy texture. Dragon fruits are also called cactus fruits. They are closely related to the orchid cacti or epiphyllum. Epiphyllums are known for their large and impressive flowers. The pitahaya can be cross pollinated with the epiphyllums.

Usage and potential
Food
The fruit is popularly eaten raw and tastes better chilled. It is also served as a juice. The flesh is sweet and sometimes served with mango in a tropical sorbet. The fruit is also used to flavour drinks while syrup made of the whole fruit is used to colour pastries and candy.
The pulp of the fruit is used in producing an alcoholic beverage. The fruit makes a wonderful cocktail on its own or mixed with other tropical fruits. It is sometimes used in cooking. Unopened flowerbuds can be cooked like vegetables.

Medicine
Dragon fruits reputedly improve eyesight and prevent hypertension. The seeds of the fruit supposed help in controlling blood glucose levels in people with non-insulin-dependent hyperglycaemic conditions (a kind of diabetes). It is also used to treat stomach and endocrine problems.

Other uses

The plant is popularly planted as a climber to cover chainlink fencing. Parts of the pitahaya plant can be used to produce food colour.

Variant names
Common name: Dragon Fruit or Dragon Pearl Fruit.
Scientific name: Hylocereus undatus, or its synonym, Cereus triangularis.
Malay name: Kaktus madu.
Chinese name: Long guo (Mandarin).
Vietnamese name: Thanh long.
Other common names: Pitahaya, Strawberry Pear, Cactus fruit, Night blooming Cereus, Belle of the Night, Cinderella plant.



Author
Naidu Ratnala Thulaja
Nor-Afidah Abd Rahman




References 
Dragon fruit exported for $45/tray. (2004, March 5). New Zealand Press Association.

Baxter, P. (2002, November 20). Fruits of labour just deliciously different. Northern Territory News (Australia), p. 5.

Lam, P. S. (2000, October 21). Desert blooms. New Straits Times, p. 8.

Morris, K. (2003, January 14). Moonflower a lady of the night. Cairns Post, p. 21.

Dan Kinnard's Pitaya Research. (2002, January 17). Retrieved May 12, 2004, from groups.yahoo.com/group/PitayaFruit/files/

International Tropical Fruits Network. (n.d.). Dragonfruit. Retrieved May 12, 2004, from www.itfnet.org/fruits.content.fm?Title=Dragonfruit

Karp. D. (1998). Breaking into the mainstream with cactus pears: Improved varieties, marketing, and Pitahaya. Journal of the Professional Association for Cactus Development. Retrieved May 12, 2004, from www.jpacd.org/Jpacd98/karp.pdf

Oregon State University. (2005, January 9). Pitahaya, food resource. Retrieved January 12, 2005, from food.oregonstate.edu/a/pitahaya.html

Trade Winds Fruit. (2004). Dragon fruit. Retrieved May 12, 2004, from www.tradewindsfruit.com/dragon_fruit.htm

Taman University, Hospital Homeopathy Nik Omar. (n.d.). Kaktus madu - dragon fruit - pitaya. Retrieved May 12, 2004, from members.langoo.com/dragonfruit/
 



The information in this article is valid as at 1998 and correct as far as we are able to ascertain from our sources. It is not intended to be an exhaustive or complete history on the subject. Please contact the Library for further reading materials on the topic.

Subject
Science and technology>>Agriculture>>Fruit crops
Nature>>Plants
Tropical fruit--Asia, Southeastern

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