The pleasures of the flesh
OPENING a mangosteen is one of life's ineffably delightful experiences, matched only by the pleasure of eating what you find inside.
Mangosteens are hard, round fruits slightly larger than golf balls. The skin is a dull, dark purple, sometimes scuffed with brown which makes them look as though they've been kicked around on their way to market. Clustered at the stem end are four prominent leathery leaf-shaped appendages (the sepals of the flower, to be precise). At the other end is a raised, pie-shaped pattern, of which the number of pieces in the ''pie'' corresponds to the number of segments of the fruit inside.
Inside are pristine white segments - much like a citrus in pattern - as tender, smooth and juicy as a ripe peach, but of unique flavour.
Origin. The mangosteen is a regional and seasonal delicacy, still defiant of entrepreneurial attempts to grow or ship it beyond its natural range. The tree grows throughout the Asian tropics but does not succeed elsewhere. The fruit perishes so readily that export is not profitable. Hence, only people in the right place at the right time can enjoy this treasure of a fruit.
In Singapore and Malaysia, mangosteens ripen about the same time as another regional, seasonal delicacy, such as the horny-rinded durian. Durains are nicknamed the King of Fruit (gwoh waang in Cantonese) and have considerable nutritional value but consumption can easily ''overheat'' a person's digestion. The perfect antidote is the cooling mangosteen, aptly nicknamed the Queen of Fruit (gwoh hau ). Both of these fruits are currently on sale in Hong Kong markets, and will be found side by side at traditional vendors' stalls.
Quality. First, check for signs of rot. Yellow juice oozing from the rind could indicate the inner segments have begun to decay. Second, check for ripeness by squeezing them gently (if not surreptitiously, under the eyes of the vendor). The rind should give slightly; those which are as hard as golf balls will probably be equally inedible. Finally, consider weight.
Heavier ones will be juicier because the rind itself, though thick, is light and porous. The colour of the skin varies from red to deep purple-black and seems to have no relevance to quality.
Storage. Store them in the fridge as you would any fruit. In good condition they will last a week for even two.
Preparation. This fruit is popularly if not exclusively enjoyed as a table fruit. It is eaten fresh, out of hand, never cooked, rarely combined, seldom served without its shell (a modest sort of fruit, but regal). The basic strategy in opening a mangosteen is to remove the rind without damaging the inner segments. The most clinical approach is with a knife. Cut through the rind - about 1.5cm deep - at its equator. This should allow you to lift the top off, like the lid of a box, exposing the fruit segments inside.
Alternatively, simply grasp the fruit in both hands and break it apart with a slight twisting motion; use enough strength to sever the rind but not enough to damage the fruit inside.
Having exposed the inner segments, extract them with fork, spoon, or directly with your teeth. Often one of the segments will be much larger than the others due to the presence of a seed. This can be eaten as well, or discarded.
There are two caveats. First, regardless of the method employed to open the fruit, take care not to let the juice of the rind get on to clothes or cloth because it stains. Secondly, once opened, the inner segments should be as pure white as the driven snow. If they are starting to darken or turn bright yellow or pink, decay has begun; with regret, discard and start on the next one.
Martha Dahlen, a botanist and food writer, has lived in Hong Kong for 15 years. She is the author of A Cook's Guide to Chinese Vegetables (Guidebook Co, $110).