The ripe sweet fruit is well-filled with vitamins A, B6 and C and contains iron, potassium, calcium and a lot of fibre. There's room for all of these with ease, because jackfruits are no little boys. They are often almost a metre long, weigh up to 50 kilos or more and grow on trees. An adult tree produces more than 200 a year.
Jackfruit and Doerian are often confused with each other. At first sight they look similar, but jackfruits are much bigger and heavier. Their skin is softer, while that of the doerian is much rougher because of the spines. Doerians are also rounder than jackfruits, which are more in the shape of a zeppelin. The flesh of the doerian looks like a big bean (or croissant, if you like), that of jackfruit looks more like coarsely ribbed yellow segments. With some imagination: overgrown corn grains.
If you're out on the streets in Thailand looking for fruit, you're more likely to find jackfruit than apples. Thailand is one of the largest jackfruit producers in the world. Much of the fruit is canned and transported to Europe, where it is usually not yet for sale.
An unripe jackfruit is also fine to eat, but because of its fibrous structure and savory taste it looks more like a vegetable. The fruit is also seen by vegetarians as a meat substitute, especially because of its good 'bite'. Unfortunately, jackfruit contains much less protein, vitamin B6 and iron than meat.
If you want to cook with jackfruit, it is best to use the unripe (young) variety. Fresh young jackfruit may not be easy to find in your area. Try tinned jackfruit instead. Pour off the liquid; to get the full flavour, gently squeeze some more water from the fruit. Jackfruit does taste fruity, but the flavour is neutral and not overpowering. Because jackfruit absorbs flavour very well, it is good for cooking. You can marinade the fleshy fruit, but jackfruit is also very suitable for many dishes when grated or pulled.
Finally, young jackfruit has a neutral fruity flavour, but mature jackfruit is sweet and has a taste somewhere between banana, mango and pineapple. Same same, but different', as they would say in Thailand.