The Jackfruit tree (botanical name Artocarpus Heterophyllus), also know as Jack tree, is a tropical tree that produces the largest fruits on the planet. You can find them in the jungles of southeast Asia and is also widely cultived in Asia, Australia, Africa and South America. The tree is also called Halasina Hannu(India), Nangka (Malaysia), kos (Sinhalese), ponas (Konkani), Palappalam (Tamil), Katahal (Hindi), and in some languages there are even different names for the different stages of the fruit.
Jackfruit
In general, when the fruit is ripe, it's sweet and can be eaten directly. When it's unripe, it's called young/green jackfruit, and it's mainly used for cooking in curries.
Westerners generally will find the jackfruit most acceptable in the full-grown but unripe stage, when it has no objectionable odor. The fruit cut into large chunks for cooking, the only handicap being its copious gummy latex which accumulates on the knife and the hands unless they are first rubbed with oil. The chunks are boiled in lightly salted water until tender, when the really delicious flesh is cut from the rind and served as a vegetable, including the seeds which, if thoroughly cooked, are mealy and agreeable.
If the jackfruit is allowed to ripen, the bulbs and seeds may be extracted outdoors; or, if indoors, the odorous residue should be removed from the kitchen at once. The bulbs may then be enjoyed raw or cooked (with coconut milk or otherwise); or made into ice cream, chutney, jam, jelly, paste, "leather" or papad, or canned in sirup made with sugar or honey with citric acid added.
The canned product is sometimes called "vegetable meat". The ripe bulbs are mechanically pulped to make jackfruit nectar or reduced to concentrate or powder.
By a method patented in India, the ripe bulbs are dried, fried in oil and salted for eating like potato chips. In Malaya, where the odor of the ripe fruit is not avoided, small jackfruits are cut in half, seeded, chilled, and brought to the table filled with ice cream.
The ripe bulbs, fermented and then distilled, produce a potent liquor. The seeds, which appeal to all tastes, may be boiled or roasted and eaten, or boiled and preserved in sirup like chestnuts. They have also been successfully canned in brine, in curry, and, like baked beans, in tomato sauce. They are often included in curried dishes. Roasted, dried seeds are ground to make a flour which is blended with wheat flour for baking.
Tender young fruits may be pickled with or without spices. Tender jackfruit leaves and young male flower clusters may be cooked and served as vegetables.
Other applications
In some areas, the jackfruit is fed to cattle. The Jackfruit tree is even planted in pastures so that the animals can avail themselves of the fallen fruits. Surplus jackfruit rind is considered a good stock food.
Jackfruit tree leaves: Young leaves are readily eaten by cattle and other livestock and are said to be fattening. In India, the leaves are used as food wrappers in cooking, and they are also fastened together for use as plates.
Latex: The latex serves as birdlime, alone or mixed with Ficus sap and oil. The heated latex is employed as a household cement for mending chinaware and earthenware, and to caulk boats and holes in buckets.
Wood: Jackwood is an important timber in former Ceylon (now Sri Lanka) and, to a lesser extent, in India; some is exported to Europe. It changes with age from orange or yellow to brown or dark-red; is termite proof, fairly resistant to fungal and bacterial decay, seasons without difficulty, resembles mahogany and is superior to teak for furniture, construction, turnery, masts, oars, implements, brush backs and musical instruments. Palaces were built of jackwood in Bali and Macassar.
From the sawdust of jackwood or chips of the heartwood, boiled with alum, there is derived a rich yellow dye commonly used for dyeing silk and the cotton robes of Buddhist priests. In Indonesia, splinters of the wood are put into the bamboo tubes collecting coconut toddy in order to impart a yellow tone to the sugar.
Sources Morton, Julia. "Jackfruit". Center for New Crops & Plant Products, Purdue University Department of Horticulture and Landscape Architecture.