Jackfruit, raw (jacob fruit, jaca fruit, nangka)

The jackfruit, also called jaca fruit, nangka, jacob fruit or jack tree fruit, is a green to yellow tropical giant fruit. It is the largest and heaviest tree fruit in the world.

Use in the kitchen:

The flesh of a ripe jackfruit ( Artocarpus heterophyllus) is light yellow to golden in color and tastes pleasantly sweet, like a mixture of pineapple and banana. The flesh usually has very little juice. In the middle of the flesh there is a thick central strand. The flesh around this strand is made up of numerous carpels, which are connected to one another by milk tubes and fibrous strands.

The strands can be a bit annoying when eaten raw. There are up to 500 seeds hidden inside the fiber strands. ¹ These seeds are smooth, light brown and look like beans that are between 2 and 4 cm in size. The seeds are edible when heated and taste similar to sweet chestnuts when cooked - or you can roast them in a pan like nuts. ² They are often used as an ingredient in curry dishes. They are also used as a side dish instead of beans or rice. ³ In India, the seeds of the jackfruit are used to make flour for chapatti (a type of flatbread) and papadams (thin, fried flatbreads). ⁴ Only 1/3 of a whole jackfruit is suitable for consumption. The rest goes into the compost. ⁵

Please note: When processing the fruit, you should wear rubber gloves because the fruit's skin secretes an extremely sticky latex juice. Oil the knife and cutting board beforehand so that the juice can be removed more easily afterwards. The sticky juice is difficult to remove not only from objects but also from textiles. ³
Cut the jackfruit and tear it in half. There is fibrous flesh around the inner stalk. Since the skin is inedible, it is separated from the flesh for further processing. ³ If the jackfruit cannot be torn, it can be cut into centimeter-thick slices and then processed further.

Ripe jackfruit pieces taste delicious raw in a fresh fruit salad. In tropical countries, the fruit is often sold in portions as a snack on the side of the road. The pulp can be pureed to make ice cream, sorbet, cake fillings, mixed juices and smoothies. For desserts made from the jackfruit, you can add a little lime or lemon juice before serving. This rounds off the sweetness of the compote particularly well. If you want to add sugar, please do not add it until after cooking. ⁶

But the jackfruit is not just a sweet tropical fruit. You can also steam, fry or boil the flesh. The jackfruit is a wonderful meat alternative, not just for vegans and vegetarians. Unripe jackfruit is actually inedible, bad for digestion and has no taste. But since 2016 the unripe fruit has been an export product as a vegan meat substitute. After cooking, the fruit fibers take on their own consistency. And with the right herb and spice mixture, the neutral, fibrous flesh, cut into small pieces and well fried, acquires a meaty taste that will amaze even convinced meat eaters.

Is jackfruit the perfect meat substitute for vegans? Video clip from September 9, 2017.

Purchasing:

A Jaca fruit looks like a knobbly, green or yellow dinosaur egg. Buying one is not easy in Europe. A specialised fruit dealer may be able to order it for you, or you can buy it from an online shop. When buying the Jaca fruit, make sure that the skin is intact. The jackfruit is climacteric. However, a fruit harvested just a little too early will unfortunately not ripen to its optimal quality. ⁷

A fully ripe fruit has a characteristic, strange smell. When the skin changes color from green to yellow-brown, this is a ripening process. The fruit also gives way when lightly pressed, and when tapped, a dull, hollow sound is heard, which indicates that the fruit is ripe. The larger the fruit, the better it tastes. ^3,7 An overripe fruit gives off a strong, unpleasant smell through the unopened skin, reminiscent of rotten onions. ⁸

There are two varieties of Jaca fruit:
Jaca Mole is a soft, small jackfruit with soft flesh that is very sweet, fibrous and juicy. The shell can be opened by hand. It is suitable for drying or freezing. ⁷
Jaca Dura is a hard, larger jackfruit with firm flesh. You definitely need a knife to open it. Apparently it is more suited to western tastes and is therefore more commercially important. ⁸

In an Asian shop you can buy the Nangka fruit pieces in cans. The preserved fruit pulp usually comes from Thailand and the Philippines. ⁵ The unripe pieces are preserved in salt water and the ripe pieces in syrup. Dried fruit pieces are also available in the Asian market as jackfruit chips or sometimes frozen pieces. ³ You might even find the fine Nangka juice, a liqueur or candied fruit pieces in an Asian import market.

Found in the wild:

The jackfruit tree ( Artocarpus heterophyllus) is, like other breadfruit trees ( Artocarpus), found in the wild. The fruit of the wild varieties has sour and dry flesh. ⁵

Storage:

An unripe jackfruit lasts for about 10 days at room temperature and ripens during this time. Below 11 °C, the Nangka shows impaired ripening behavior. If it is already ripe, it will last for about 2-6 weeks at 13 °C if the relative humidity is at least 90 percent. ⁷ An opened jackfruit or its pieces can be kept in the refrigerator for a few days.

Ingredients:

Jackfruit is rich in starch, contains hardly any protein or fat and a small amount of fiber. Vitamins such as pyridoxine (B₆), thiamine (B₁), vitamin C, vitamin A and folic acid are present in the fruit. Of the minerals, the potassium content is particularly high. Magnesium, calcium and phosphorus are also found in the flesh of the jackfruit. ⁹ You can find detailed information in the ingredient tables after the text.

Health aspects:

Basically, jackfruit is a nutrient-rich staple food for rural communities in the countries of origin. The pulp is a perfect substitute for rice. The starch nourishes and the fiber helps regulate the intestinal flora.

Potassium plays a central role in the transmission of stimuli in the nervous system and in regulating the body's water balance. It also regulates blood pressure and ensures that the muscles work well. The calcium in Nangka strengthens the bones and teeth. Vitamin A stimulates cell production in the skin and mucous membranes, supports the metabolism and is important for eyesight. The vitamin C it contains protects the immune system.

The saponins, lignans and isoflavones contained in jackfruit are valuable plant ingredients that are said to have an anti-cancer effect. However, there are still no significant studies on this. Saponins, which are said to prevent colon cancer, are mainly found in the leaves and trunk of the jackfruit tree and less in the fruit. ¹⁰ Jacalin, a lectin, contained in jackfruit is said to have antiviral properties. In highly concentrated form, in-vitro studies have shown positive effects against HIV and herpes viruses. In comparison, however, the fruit contains only a small dose of this. ¹¹

Dangers / Intolerances:

The seeds of the Jaca contain a toxin. In order to neutralize the toxin and to be able to eat them, the seeds must be cooked, roasted, grilled or boiled.

People who are allergic to birch pollen should be careful when eating jackfruit. Allergic reactions can occur due to cross-allergies. ¹²

Folk medicine

The jaca fruit is said to be effective in combating respiratory infections. It is used therapeutically for all types of coughs. ⁶ The seeds of the nangka fruit are also said to speed up the healing process if you are suffering from an intestinal infection. ¹³

According to the English botanist Isaac Burkill (1870-1965), the juice of the pressed roots of the Nangka bubor contains a fever-reducing substance. Heated leaves of the jackfruit tree are said to provide relief for wounds. ⁵ The bark of the jackfruit tree releases a milky liquid when scratched. This juice is said to have a healing effect on eye irritations. ⁶

Occurrence:

The jackfruit or nangka originally comes from southern India. From there it was brought to Brazil and almost all tropical regions of the world. The largest areas where jackfruit is grown are in Kerala, a well-developed state in southwest India that has been independent since 1974. There the jaca fruit is even considered the national fruit. In addition to India, other main areas where the exotic jackfruit is grown today are Thailand, Bangladesh, Malaysia, Sri Lanka, Indonesia and Nepal. ^13.6 The nangka fruit is also cultivated in Brazil, the Caribbean, Australia and several African countries. ⁷

Cultivation, harvest:

The jackfruit tree grows up to 25 meters high. The trunk is straight as an arrow and can have a diameter of more than 1 meter. The inflorescences are grouped directly on woody parts of the plant, i.e. on the trunk and on the strongest branches (cauliflory). The tree is monoecious, which means that each tree has male and female flowers that are visually different from each other. The female flowers normally grow closer to the trunk and contain a single-chambered ovary, from which the pseudofruits later develop.

The crown of the tree is irregular and has long, leathery, dark green, shiny leaves. The tree loves a warm, humid climate and an average annual temperature of 25 degrees. In semi-arid climates it also thrives with artificial irrigation. It can grow at altitudes of up to 1100 m above sea level, but does not tolerate frost.

The Singapore Nangka bears fruit three years after planting. Other tree varieties take almost eight years to produce their first harvest. ⁵ A jackfruit takes 180 to 200 days to grow. Each year, a tree bears around 30 fruits, which are attached to a long, thick stem. The exotic fruit is usually harvested for the European market when it is unripe in July and August. The fruit ripens later, like the banana, and has a long journey ahead of it. But that is not the only reason for the early harvest: if there are too many fruits on the tree, the riper ones have to be harvested so that the remaining ones can ripen even better. ^3,14

The best quality of jackfruit (jacafruit, jacobfruit) is said to grow near Nakhon Si Thammarat ⁸ - in a fertile coastal plain about 780 km south of Bangkok on the Gulf of Thailand.

The Jaca fruit is the largest of all cultivated fruits. The fruit has an unusual, oval shape and a thick green skin with small bumps. The curious fruits can reach a weight of more than 15 kg and a length of up to 90 cm. The fruit diameter can be between 13 and 50 cm. ⁶

Danger of confusion:

The breadfruit ( Artocarpus altilis) is very similar to the jackfruit. It can also be confused with the durian fruit ( Durio zibethinus) from the mallow family (Malvaceae). Unlike the jackfruit, the durian does not have a knobbly shell, but rather a prickly shell. If you cut open the shell of the durian fruit, the fruit smells very strong. This is why the durian is also called the stink fruit or vomit fruit. ³

The baobab fruit is a 25-40 cm long, edible fruit that hangs on long stems from the crown of the African baobab tree ( Adansonia digitata). The tree also belongs to the mallow family and is one of the best known and most characteristic trees in Africa.

General information:

The jackfruit ( Artocarpus heterophyllus) belongs to the mulberry family (Moraceae). The fruit gets its name from the Malaysian Hindu name “Chakka”. This means “round” and simply describes its appearance.

In Sri Lanka, the jackfruit tree is protected. A tree may only be felled with the permission of the authorities. ¹³ During the colonial period, it was legally required that every family on the island had two jackfruit trees. This ensured a source of food all year round. ¹⁵

In its countries of origin, the tree is often used today as a windbreak and to provide shade for grazing livestock. The green tree leaves, when chopped or ground, are an important food source for birds, goats and other domestic animals. ⁶

The wood of the jaca tree is a precious wood. It has a white to greyish colour and darkens when it comes into contact with the air. When oxidised, it looks very similar to mahogany. The boat building industry is very coveted for this valuable wood. ^6.1

Wikipedia on this: The wood of the jackfruit tree is medium hard, weatherproof, termite resistant and can be polished well. It is highly valued as furniture wood and is used to make musical instruments; in Indonesia (Indonesian pohon nangka) for the frames of some gongs and the barrel drum kendang in the gamelan as well as the plucked lute gambus, in India for the barrel drum maddale, the cylinder drum chenda played in Kerala and sometimes the hourglass drum idakka. In this southern Indian state, the tree (Malayalam varikka plavu) is considered sacred and the home of the Hindu goddess Kali. Therefore, altarpieces of the goddess and the crown for the main actor in the religious dance drama Mutiyettu are ritually made from jackfruit wood. ¹³

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