Synonym: Artocapus heterophyllus, Artocarpus integrifolius, Artocarpus integrifolia, Artocarpus integra.
Jackfruit, nangka, jaca, jakfruit.
The jackfruit tree is handsome and stately. In the tropics it grows to an enormous size, like a large eastern oak. In California it is very doubtful that it would ever approach this size. All parts contain a sticky, white latex.
The leaves are oblong, oval, or elliptic in form, 4 to 6 inches in length, leathery, glossy, and deep green in color. Juvenile leaves are lobed.
Male and female flowers are borne in separate flower-heads. Male flower-heads are on new wood among the leaves or above the female. They are swollen, oblong, from an inch to four inches long and up to an inch wide at the widest part. They are pale green at first, then darken. When mature the head is covered with yellow pollen that falls rapidly after flowering. The female heads appear on short, stout twigs that emerge from the trunk and large branches, or even from the soil-covered base of very old trees. They look like the male heads but without pollen, and soon begins to swell. The stalks of both male and female flower-heads are encircled by a small green ring.
Jackfruit is the largest tree-borne fruit in the world, reaching 80 pounds in weight and up to 36 inches long and 20 inches in diameter. The exterior of the compound fruit is green or yellow when ripe. The interior consists of large edible bulbs of yellow, banana-flavored flesh that encloses a smooth, oval, light-brown seed. The seed is 3/4 to 1-1/2 inches long and 1/2 to 3/4 inches thick and is white and crisp within. There may be 100 or up to 500 seeds in a single fruit, which are viable for no more than three or four days. When fully ripe, the unopened jackfruit emits a strong disagreeable odor, resembling that of decayed onions, while the pulp of the opened fruit smells of pineapple and banana.
There are two main varieties. In one, the fruits have small, fibrous, soft, mushy, but very sweet carpels with a texture somewhat akin to a raw oysters. The other variety is crisp and almost crunchy though not quite as sweet. This form is the more important commercially and is more palatable to western tastes.
Westerners generally will find the jackfruit most acceptable in the full-grown but unripe stage, when it has no objectionable odor and excels cooked green breadfruit and plantain. The fruit at this time is simply 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 salad 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. The latex clinging to the pot may be removed by rubbing with oil. The flesh of the unripe fruit has been experimentally canned in brine or with curry. It may also be dried and kept in tins for a year. Cross sections of dried, unripe jackfruit are sold in native markets in Thailand. Tender young fruits may be pickled with or without spices.
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 crisp types of jackfruit are preferred for canning. The canned product is more attractive than the fresh pulp and is sometimes called "vegetable meat". The ripe bulbs are mechanically pulped to make jackfruit nectar or reduced to concentrate or powder. The addition of synthetic flavoring—ethyl and n-butyl esters of 4-hydroxybutyric acid at 120 ppm and 100 ppm, respectively greatly improves the flavor of the canned fruit and the nectar.
If the bulbs are boiled in milk, the latter when drained off and cooled will congeal and form a pleasant, orange colored custard. By a method patented in India, the ripe bulbs may be dried, fried in oil and salted for eating like potato chips. Candied jackfruit pulp in boxes was being marketed in Brazil in 1917. Improved methods of preserving and candying jackfruit pulp have been devised at the Central Food Technological Research Institute, Mysore, India. Ripe bulbs, sliced and packed in sirup with added citric acid, and frozen, retain good color, flavor and texture for one year. Canned jackfruit retains quality for 63 weeks at room temperature—75° to 80°F (23.89°-26.67°C), with only 3% loss of B-carotene. When frozen, the canned pulp keeps well for 2 years.
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.
Where large quantities of jackfruit are available, it is worthwhile to utilize the inedible portion, and the rind has been found to yield a fair jelly with citric acid. A pectin extract can be made from the peel, undeveloped perianths and core, or just from the inner rind; and this waste also yields a sirup used for tobacco curing.
Fruit: In some areas, the jackfruit is fed to cattle. The 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.
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 from Schleichera trijuga Willd. The heated latex is employed as a household cement for mending chinaware and earthenware, and to caulk boats and holes in buckets. The chemical constituents of the latex have been reported by Tanchico and Magpanlay. It is not a substitue for rubber but contains 82.6 to 86.4% resins which may have value in varnishes. Its bacteriolytic activity is equal to that of papaya latex.
Wood: Jackwood is an important timber in Ceylon 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, and the limited supply was once reserved for temples in Indochina. Its strength is 75 to 80% that of teak. Though sharp tools are needed to achieve a smooth surface, it polishes beautifully. Roots of old trees are greatly prized for carving and picture framing. Dried branches are employed to produce fire by friction in religious ceremonies in Malabar.
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. Besides the yellow colorant, morin, the wood contains the colorless cyanomaclurin and a new yellow coloring matter, artocarpin, was reported by workers in Bombay in 1955. Six other flavonoids have been isolated at the National Chemical Laboratory, Poona.
Bark: There is only 3.3% tannin in the bark which is occasionally made into cordage or cloth.
The Chinese consider jackfruit pulp and seeds tonic, cooling and nutritious, and to be "useful in overcoming the influence of alcohol on the system." The seed starch is given to relieve biliousness and the roasted seeds are regarded as aphrodisiac. The ash of jackfruit leaves, burned with corn and coconut shells, is used alone or mixed with coconut oil to heal ulcers. The dried latex yields artostenone, convertible to artosterone, a compound with marked androgenic action. Mixed with vinegar, the latex promotes healing of abscesses, snakebite and glandular swellings. The root is a remedy for skin diseases and asthma. An extract of the root is taken in cases of fever and diarrhea. The bark is made into poultices. Heated leaves are placed on wounds. The wood has a sedative property; its pith is said to produce abortion.
* Jackfruit has many medicinal uses as listed below:
* Root extract is used to treat fever and diarrhoea.
* The root is a remedy for skin diseases and asthma.
* The bark is used as a poultice.
* The wood has a sedative property.
* The jackfruit pulp and the seeds are considered a tonic by the Chinese.
* It also helps one get over the influence of alcohol.
* The starch from the seeds is used to relieve biliousness The roasted seeds are said to be an aphrodisiac.
* The burnt residue of jackfruit leaves mixed with burnt corn and coconut shells is used to heal ulcers.
* It is also a good source of vitamin B1 and B2.