Jackfruit

The jackfruit, jakfruit or nangka is a species of tree in the fig, mulberry, and breadfruit family.
The jackfruit is the largest tree fruit, reaching as much as in weight, in length, and in diameter. A mature jackfruit tree produces some 200 fruits per year, with older trees bearing up to 500 fruits in a year. The jackfruit is a multiple fruit composed of hundreds to thousands of individual flowers; the fleshy petals of the unripe fruit are eaten by humans, in addition to the ripened fruit.
The jackfruit tree is well-suited to tropical lowlands and is widely cultivated throughout tropical regions of the world, particularly from South Asia to Southeast Asia and Oceania.
Its ripe fruit can be sweet depending on grown variety, which is commonly used in desserts. Canned green jackfruit has a mild taste and meat-like texture that lends itself to being called "vegetable meat". Jackfruit is commonly used in South and Southeast Asian cuisines. Both ripe and unripe fruits are consumed. It is available internationally, canned or frozen, and in chilled meals, as are various products derived from the fruit, such as noodles and chips.

Names

The name jackfruit comes from Portuguese jaca added by physician and naturalist Garcia de Orta in his 1563 book Colóquios dos simples e drogas da India. In turn, jaca is derived from the Malayalam word ചക്ക chakka, when the Portuguese Empire arrived in India at Calicut on the Malabar Coast in 1499. Later the Malayalam name chakka was recorded by Hendrik van Rheede in the third volume of Hortus Malabaricus. Henry Yule translated Hendrik's book in Jordanus Catalani's Mirabilia descripta: the wonders of the East. The Malayalam ചക്ക chakka is derived from the Proto-Dravidian root kā.
Centuries later, botanist Ralph Randles Stewart suggested it was named after William Jack, a Scottish botanist who worked for the East India Company in Bengal, Sumatra, and Malaya.
Nangka is another name used in Philippine English borrowing from Tagalog related to nangkà in Cebuano and in Malay, both from the same Austronesian language family.

Description

Shape, trunk and leaves

Artocarpus heterophyllus grows as an evergreen tree that has a relatively short trunk and dense treetop. It easily reaches heights of and trunk diameters of. It sometimes forms buttress roots. The bark of the jackfruit tree is reddish-brown and smooth. In the event of injury to the bark, a milky sap is released.
The leaves are alternate and spirally arranged. They are gummy and thick and are divided into a petiole and a leaf blade. The petiole is long. The leathery leaf blade is long and wide, and is oblong to ovate in shape.
In young trees, the leaf edges are irregularly lobed or split. On older trees, the leaves are rounded and dark green, with a smooth leaf margin. The leaf blade has a prominent main nerve and, starting on each side, six to eight lateral nerves. The stipules are egg-shaped at a length of.

Flowers

The inflorescences are formed on the trunk, branches or twigs. Jackfruit trees are monoecious, having both female and male flowers on a tree. The inflorescences are pedunculated, cylindrical to ellipsoidal or pear-shaped, to about long and wide. Inflorescences are initially completely enveloped in egg-shaped cover sheets which rapidly slough off.
The flowers are small, sitting on a fleshy rachis. The male flowers are greenish, some flowers are sterile. The male flowers are hairy and the perianth ends with two membrane. The individual and prominent stamens are straight with yellow, roundish anthers. Pollen grains are tiny, around 60 microns in diameter. After the pollen distribution, the stamens become ash-gray and fall off after a few days. Later, all the male inflorescences also fall off. The greenish female flowers, with hairy and tubular perianth, have a fleshy flower-like base. The female flowers contain an ovary with a broad, capitate, or rarely bilobed scar. The blooming time ranges from December until February or March.

Fruit

The ellipsoidal to roundish fruit is a multiple fruit formed from the fusion of the ovaries of multiple flowers. The fruits grow on a long and thick stem on the trunk. They vary in size and ripen from an initially yellowish-greenish to yellow, and then at maturity to yellowish-brown. They possess a hard, gummy shell with small pimples surrounded with hard, hexagonal tubercles. The large and variously shaped fruit have a length of and a diameter of and can weigh up to the largest of all tree-borne fruits.
The fruits consist of a fibrous, whitish core about thick. Radiating from this are many individual fruits, long. They are elliptical to egg-shaped, light brownish achenes with a length of about and a diameter of.
There may be about 100–500 seeds per fruit. The seed coat consists of a thin, waxy, parchment-like and easily removable testa and a brownish, membranous tegmen. The cotyledons are usually unequal in size, and the endosperm is minimally present. An average fruit consists of 27% edible seed coat, 15% edible seeds, 20% white pulp and bark and 10% core.
The fruit matures during the rainy season from July to August. The bean-shaped achenes of the jackfruit are coated with a firm yellowish aril, which has an intense sweet taste at maturity of the fruit. The pulp is enveloped by many narrow strands of fiber, which run between the hard shell and the core of the fruit and are firmly attached to it. When pruned, the inner part secretes a sticky, milky liquid, which is hard to remove from the skin, even with soap and water. To clean the hands after "unwinding" the pulp, an oil or other solvent is used. For example, street vendors in Tanzania, who sell the fruit in small segments, provide small bowls of kerosene for their customers to cleanse their sticky fingers.
When fully ripe, jackfruit has a strong aroma which is pleasant to some, unpleasant to others. The odor of the pulp of the opened fruit resembles those of pineapple and banana; in a study of flavour volatiles in five jackfruit cultivars, the main volatile compounds detected were ethyl isovalerate, propyl isovalerate, butyl isovalerate, isobutyl isovalerate, 3-methylbutyl acetate, 1-butanol, and 2-methylbutan-1-ol.

Ecology

The species has expanded excessively because its fruits, which naturally fall to the ground and open, are eagerly eaten by small mammals, such as the common marmoset and coati. The seeds are then dispersed by these animals, spreading jackfruit trees that compete for space with native tree species. The supply of jackfruit has allowed the marmoset and coati populations to expand. Since both prey opportunistically on bird eggs and nestlings, the increase in marmoset and coati populations is detrimental to local birds.

As an invasive species

The jackfruit can become an invasive species as in Brazil's Tijuca Forest National Park in Rio de Janeiro or at the Horto Florestal in neighbouring Niterói. The Tijuca is mostly an artificial secondary forest, whose planting began during the mid-nineteenth century; jackfruit trees have been a part of the park's flora since it was founded.

Cultivation

History

The geographic origin of the jackfruit is not precisely known, although it may have arisen in the Western Ghats. The fruit was later introduced to Guam via Filipino settlers when both were part of the Spanish Empire. Early cultivation also occurred in Myanmar, Sri Lanka, southern China, and the East Indies.

Care

In terms of taking care of the plant, minimal pruning is required; cutting off dead branches from the interior of the tree is only sometimes needed. In addition, twigs bearing fruit must be twisted or cut down to the trunk to induce growth for the next season. Branches should be pruned every three to four years to maintain productivity.
Some trees carry too many mediocre fruits and these are usually removed to allow the others to develop better to maturity.
Stingless bees such as Tetragonula iridipennis are jackfruit pollinators, and so play an important role in jackfruit cultivation. It seems to be the case that pollination results from a three-way mutualism involving the flower, a fungus, and a species of gall midge, Clinidiplosis ultracrepidata. The fungus forms a film over the syncarps which is a food source to both the fly larvae and adults.

Production and marketing

In 2017, India produced of jackfruit, followed by Bangladesh, Thailand, and Indonesia.
The marketing of jackfruit involves three groups: producers, traders, and middlemen, including wholesalers and retailers. The marketing channels are rather complex. Large farms sell immature fruit to wholesalers, which helps cash flow and reduces risk, whereas medium-sized farms sell the fruit directly to local markets or retailers.

Commercial availability

Outside countries of origin, fresh jackfruit can be found at food markets throughout Southeast Asia. It is also extensively cultivated in the Brazilian coastal region, where it is sold in local markets. It is available canned in sugary syrup, or frozen, already prepared and cut. Jackfruit industries are established in Sri Lanka and Vietnam, where the fruit is processed into products such as flour, noodles, papad, and ice cream. It is also canned and sold as a vegetable for export.
Jackfruit is also widely available year-round, both canned and dried. Dried jackfruit chips are produced by various manufacturers. As reported in 2019, jackfruit became more widely available in US grocery stores, cleaned and ready to cook, as well as in premade dishes or prepared ingredients. It is on restaurant menus in preparations such as taco fillings and vegan versions of pulled pork dishes.

Uses

Nutrition

The edible raw pulp is 74% water, 23% carbohydrates, 2% protein, and 1% fat. The carbohydrate component is primarily sugars, and is a source of dietary fiber. In a reference amount of, raw jackfruit provides 95 kilocalories, and is a moderate source of vitamin B₆, vitamin C, and potassium, with no significant content of other micronutrients.
The jackfruit is a partial solution for food security in developing countries.