Mangosteen


Mangosteen, sometimes rendered mangostan, and commonly known as the purple mangosteen, is a tropical evergreen tree with edible fruit native to the Malay Peninsula and Borneo. It has been cultivated extensively in tropical Asia since ancient times. It is grown mainly in Southeast Asia, southwest India and other tropical areas such as Colombia, Puerto Rico and Florida, where the tree has been introduced. The tree grows from tall.
The fruit of the mangosteen is sweet and tangy, juicy, somewhat fibrous, with fluid-filled vesicles and an inedible, deep reddish-purple colored rind when ripe. The fragrant edible flesh that surrounds each seed is the endocarp, i.e., the inner layer of the ovary. The seeds are of similar size and shape to almonds.
The genus Garcinia also contains several less-known fruit-bearing species, such as the button mangosteen and the charichuelo.

Description

Tree

A tropical tree, the mangosteen must be grown in consistently warm conditions, as exposure to temperatures below for prolonged periods will usually kill a mature plant. They are known to recover from brief cold spells rather well, often with damage only to young growth. Experienced horticulturists have grown this species outdoors, and brought them to fruit in extreme south Florida.
The tree grows from tall.

Fruit

The juvenile mangosteen fruit, which does not require fertilisation to form, first appears as pale green or almost white in the shade of the canopy. As the fruit enlarges over the next two to three months, the exocarp colour deepens to darker green. During this period, the fruit increases in size until its exocarp is in outside diameter, remaining hard until a final, abrupt ripening stage.
The subsurface chemistry of the mangosteen exocarp comprises an array of polyphenols, including xanthones and tannins that assure astringency which discourages infestation by insects, fungi, plant viruses, bacteria, and animal predation while the fruit is immature. Colour changes and softening of the exocarp are natural processes of ripening that indicate the fruit can be eaten and the seeds have finished developing.
Once the developing mangosteen fruit has stopped expanding, chlorophyll synthesis slows as the next colour phase begins. Initially streaked with red, the exocarp pigmentation transitions from green to red to dark purple, indicating a final ripening stage. This entire process takes place over a period of ten days as the edible quality of the fruit peaks. Over the days following removal from the tree, the exocarp hardens to an extent depending upon post-harvest handling and ambient storage conditions, especially relative humidity levels. If the ambient humidity is high, exocarp hardening may take a week or longer when the flesh quality is peaking and excellent for consumption. However, after several additional days of storage, especially if unrefrigerated, the flesh inside the fruit might spoil without any obvious external indications. Using the hardness of the rind as an indicator of freshness for the first two weeks following harvest is therefore unreliable because the rind does not accurately reveal the interior condition of the flesh. If the exocarp is soft and yielding as it is when ripe and fresh from the tree, the fruit is usually good.
The edible endocarp of the mangosteen has the same shape and size as a tangerine in diameter, but is white. The number of fruit segments corresponds exactly with the number of stigma lobes on the exterior apex; accordingly, a higher number of fleshy segments also corresponds with the fewest seeds. The circle of wedge-shaped segments contains 4–8, rarely 9 segments, the larger ones harbouring the apomictic seeds that are unpalatable unless roasted. As a non-climacteric fruit, picked mangosteen does not ripen further, so it must be consumed shortly after harvest.
Often described as a subtle delicacy, the flesh bears an exceptionally mild aroma, quantitatively having about 1/400th of the chemical constituents of fragrant fruits, explaining its relative mildness. The main volatile components having caramel, grass and butter notes as part of the mangosteen fragrance are hexyl acetate, hexenol and α-copaene. Ethyl octanoate, ethyl hexanoate and 3-methyl-2-butene-1-thiol were detected as aroma components in mangosteen wine.

Origins and history

Cultivated mangosteen is dioecious, but male trees are unknown. The trees produce viable seeds via apomixis, where all the embryos are essentially clones of the mother. Its extensive cultivation has made its original native range difficult to ascertain. Garcinia mangostana var. mangostana is likely to be the domesticated descendant of wild populations of Garcinia mangostana var. malaccensis and Garcinia mangostana var. borneensis, native to the Malay Peninsula and Borneo respectively. Both of these wild varieties still possess male trees, unlike the domesticated mangosteen. It may have also hybridized to a limited extent with closely related species, including Garcinia penangiana and Garcinia venulosa.
Mangosteens are highly valued for their juicy, delicate texture and slightly sweet and sour flavor. The mangosteen has been cultivated in Malaysia, Sri Lanka, Borneo, Sumatra, Mainland Southeast Asia, and the Philippines since ancient times. The 15th-century Chinese record Yingya Shenglan described mangosteen as mang-chi-shih, a native plant of Southeast Asia of white flesh with a delectable sweet and sour taste.
A description of mangosteen was included in the Species Plantarum by Linnaeus in 1753. The mangosteen was introduced into English greenhouses in 1855. Subsequently, its culture was introduced into the Western Hemisphere, where it became established in West Indies islands, especially Jamaica. It was later established on the American mainland in Guatemala, Honduras, Panama, and Ecuador. The mangosteen tree generally does not grow well outside the tropics.
In Southeast Asia, mangosteen is commonly known as the "Queen of Fruits", and is frequently paired with durian, the "King of Fruits". In Chinese food therapy, mangosteen is considered "cooling", making it a good counterbalance to the "heaty" durian. There is also a legend about Queen Victoria offering a reward of one hundred pounds sterling to anyone who could deliver a fresh mangosteen to her. Although this legend can be traced to a 1930 publication by the fruit explorer David Fairchild, it is not substantiated by any known historical document.
The journalist and gourmetR. W. Apple Jr. once said of the fruit, "No other fruit, for me, is so thrillingly, intoxicatingly luscious...I'd rather eat one than a hot fudge sundae, which for a big Ohio boy is saying a lot." Since 2006, private small-volume orders for fruits grown in Puerto Rico have been sold to American specialty food stores and gourmet restaurants who serve the flesh segments as a delicacy dessert.

Propagation, cultivation and harvest

Mangosteen is usually propagated by seedlings. Vegetative propagation is difficult and seedlings are more robust and reach fruiting earlier than vegetatively propagated plants.
Mangosteen produces a recalcitrant seed which is not a true seed strictly defined, but rather described as a nucellar asexual embryo. As seed formation involves no sexual fertilization, the seedling is genetically identical to the mother plant. If allowed to dry, a seed dies quickly, but if soaked, seed germination takes between 14 and 21 days when the plant can be kept in a nursery for about 2 years growing in a small pot.
When the trees are approximately, they are transplanted to the field at a spacing of. After planting, the field is mulched in order to control weeds. Transplanting takes place in the rainy season because young trees are likely to be damaged by drought. Because young trees need shade, intercropping with banana, plantain, rambutan, durian or coconut leaves is effective. Coconut palms are mainly used in areas with a long dry season, as palms also provide shade for mature mangosteen trees. Another advantage of intercropping in mangosteen cultivation is the suppression of weeds.
The growth of the trees is slowed if the temperature is below. The ideal temperature range for growing and producing fruits is with relative humidity over 80%. The maximal temperature is, with both leaves and fruit being susceptible to scorching and sunburn, while the minimum temperature is. Young seedlings prefer a high level of shade and mature trees are shade-tolerant.
Mangosteen trees have a weak root system and prefer deep, well-drained soils with high moisture content, often growing on riverbanks. The mangosteen is not adapted to limestone soils, alluvial soils, or sandy soils with low organic matter content. Mangosteen trees need a well-distributed rainfall over the year and a 3–5 week dry season.
Mangosteen trees are sensitive to water availability and application of fertilizer input which is increased with the age of trees, regardless of region. Maturation of mangosteen fruits takes 5–6 months, with harvest occurring when the pericarps are purple.

Breeding

In the breeding of perennial mangosteen, the selection of rootstock and grafting are significant issues to overcome constraints to production, harvesting, or seasonality. Most of the genetic resources for breeding are in germplasm collections, whereas some wild species are cultivated in Malaysia and the Philippines. Conservation methods are chosen because storage of seeds under dried and low-temperature conditions has not been successful.
Because of the long duration until the trees yield fruits and the long resulting breeding cycles, mangosteen breeding has not proven attractive for transplanting or research. Breeding objectives that may enhance mangosteen production include:
  • Drought tolerance, especially sensitivity to drought in the first 5 years after germination
  • Tree architecture to produce a tree with a crown that is regular and pyramid-shaped
  • Fruit quality including i) overcoming bitter taste components caused by changes in pulp, pericarp or aril and ii) pericarp cracking resulting from excessive water uptake
  • Rootstock for improved adaptation to drought and robust development in early years of growth