is a tropical evergreen tree. It is believed to have originated in the Sunda Islands and the Moluccas of Indonesia. The tree grows from 7 to 25 m (20 - 80 ft) tall. The rind is deep reddish purple when ripe. Botanically an aril, the fragrant edible flesh can be described as sweet and tangy, citrusy with peach flavor and texture.
The Purple Mangosteen belongs to the same genus as the other less widely known mangosteens, such as the Button Mangosteen (G. prainiana
) or the Lemondrop Mangosteen (G. madruno
). Botanically, they are not related to the mango (Mangifera spp.), which belongs to the Anacardiaceae plant family.
As the mangosteen fruit ripens, chlorophyll synthesis slows as the next color phase begins. Initially the fruit is streaked with red, the outer layer changes colour 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. Following removal from the tree, the skin (or to be exact, exocarp) hardens to an extent depending upon post-harvest handling and ambient storage conditions, especially humidity. If the ambient humidity is high, exocarp hardening may take a week or longer when the aril quality is peaking and excellent for consumption. If unrefrigerated, the flesh inside the fruit might spoil without any obvious indications outside. Using 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 arils. If the exocarp is soft and yielding as it is when ripe and fresh from the tree, the fruit is usually good.
The edible flesh of the mangosteen is botanically defined as an aril with the same shape and size as a tangerine. It is usually 4 - 6 centimeters in diameter, but is white. The circle of wedge-shaped arils contains 4 - 8 segments, the larger ones harboring apomictic seeds that are unpalatable unless roasted. Often described as a subtle delicacy, the arils bear an exceptionally mild aroma, quantitatively having about 400 times fewer chemical constituents than fragrant fruits, which explains its relative mildness. On the bottom of the exocarp are raised ridges arranged like spokes of a wheel. They correspond to the number of aril sections inside the fruit. Mangosteens reach fruit-bearing in as little as 5 - 6 years, but more typically require 8 - 10 years.