| Longan Dimocarpus longan |
|
|---|---|
| Longan fruit | |
| Conservation status | |
| Scientific classification | |
| Kingdom: | Plantae |
| (unranked): | Angiosperms |
| (unranked): | Eudicots |
| (unranked): | Rosids |
| Order: | Sapindales |
| Family: | Sapindaceae |
| Genus: | Dimocarpus |
| Species: | D. longan |
| Binomial name | |
| Dimocarpus longan Lour. |
|
| Synonyms | |
|
Euphoria longan Steud. |
|
Dimocarpus longan, commonly known as the longan, is a tropical tree native to South and Southeast Asia,[1] in the Indomalaya ecozone.[2] It produces edible fruit.
Contents |
The fruit is known as longan or longyan in English. It is also known as, in simplified Chinese: 龙眼; traditional Chinese: 龍眼; Mandarin Pinyin: lóngyǎn; Jyutping: lung4 ngaan5; literally "dragon eye", in Lao: ລໍາໄຍ Lam Yai, in Vietnamese: Long Nhãn/Nhãn, in Malaysian: mata kucing, literally "cat's eye", in Indonesian: Kelengkeng, in Sinhala: Mora or Lengkeng, in Thai: ลำไย Lam Yai, in Filipino: Longan, in Bangladesh : Ashfol, Tamil: முதலிப் பழம் (Muthali Pazham)
The Dimocarpus longan tree can grow up to 6 to 7 metres in height, and the plant is very sensitive to frost. Longan trees require sandy soil and temperatures that do not typically go below 4.5 degrees Celsius (40.1 degrees Fahrenheit). Longans and lychees bear fruit at around the same time of the year.
The longan (translated literally as "dragon eye") is so named (from its transliteration from Amoy) [liong-gan] because its fruit, when it is shelled, resembles an eyeball (the black seed shows through the translucent flesh like a pupil/iris). The seed is small, round and hard, and of an enamel-like, lacquered black. The fully ripened, freshly harvested shell is bark-like, thin, and firm, making the fruit easy to shell by squeezing the fruit out as if one is "cracking" a sunflower seed. When the shell has more moisture content and is more tender, the fruit becomes less convenient to shell. The tenderness of the shell varies due to either premature harvest, variety, weather conditions, or transport/storage conditions.
The longan is listed as Near Threatened on the IUCN Red List.[3]
The fruit is edible, extremely sweet, juicy and succulent in superior agricultural varieties, and apart from being eaten fresh, is also often used in East Asian soups, snacks, desserts, and sweet-and-sour foods, either fresh or dried, sometimes canned with syrup in supermarkets.
Dried longan, called guìyuán (桂圆) in Chinese, are often used in Chinese cuisine and Chinese sweet dessert soups. In Chinese food therapy and herbal medicine, it is believed to have an effect on relaxation. In contrast with the fresh fruit, which is juicy and white, the flesh of dried longans is dark brown to almost black. In Chinese medicine the longan, much like the lychee, is thought to give internal "heat" (上火).
Potassium chlorate has been found to cause the longan tree to blossom. However, this causes stress on the tree if it is used excessively, and eventually kills it.[4]