Common name: Breadfruit

Breadfruit is one of the most important food trees of the tropics, the fruit being a staple for many and, as its name suggests, a substitute for bread.

Originating in the Old World tropics, the tree's natural range extends from Malaysia, through Indonesia and Papua New Guinea, to Polynesia in the Western Pacific.

Breadfruit falls into two main types: seeded and non-seeded. Non-seeded types, also known as sterile types, are the most widely eaten and the focus of this description.

It may grow into a large tree up to 30 m (100 ft) tall, though it is typically between 15 and 20 m (50 to 65 ft) tall, with a straight trunk supporting a densely leafy, rounded crown. The bark is grey-brown, smooth on young trees, becoming mottled, cracked, and rough with age, and, on wounding, yields a sticky white latex, as do all parts of the tree.

Leaves are large, up to 30 cm (12 in) across, deeply lobed, dark glossy green on top, pale dull green underneath. Although the tree is evergreen, it sheds leaves continuously throughout the year. The old leaves turn first yellow, then brown and papery, before falling to the ground.

Flowers are small and insignificant, held in clusters of male or female flowers on the same tree. The male flowers are tightly packed in club-shaped spikes up to 30 cm (12 in) long, the female flowers in smaller oval-shaped spikes, and there are up to two thousand flowers on each spike.

Flowering is continuous in humid climates, but fruiting is most abundant in the rainy season and in the two to three months that follow. The fruits are oval to round and large, up to 20 cm (8 in) in diameter. When young, they have bright green skin that becomes dull green with age, with brown mottling caused by latex droplets drying on the surface.

There are many varieties of seedless breadfruit, varying in fruit shape and size, as well as leaf shape and size. However, they are most commonly distinguished by pulp colour, which has given rise to two named types: 'White heart' and 'Yellow heart'.

Mature breadfruit

Edible uses

For most uses, harvest the fruit at the mature but still unripe stage, when the pulp is firm and has not yet softened; it becomes nearly liquid once fully ripe.

Cooked vegetable - The most popular way to prepare mature breadfruit is to roast it whole in its skin, especially over hot coals, which chars and blackens the skin. Once peeled, the steaming white or pale yellow pulp is slightly sweet and spongy, and eaten like warm, freshly baked bread, sometimes even spread with butter.

In the French-speaking Caribbean, the boiled pulp is mashed, seasoned, and formed into small balls stuffed with meat or other ingredients, then crumbed and fried to a golden crisp; known as 'Boulettes,' they are a popular snack or starchy accompaniment to a meal, and breadfruit croquettes are made similarly.

Boiled and diced breadfruit is also used to make a mock potato salad, substituting for potatoes in a mayonnaise-based sauce.

Flour - The pulp of mature fruit can be dried and ground to make a gluten-free flour, suitable for mixing with other flours to make bread, cakes, and other baked goods. Breadfruit flour contains about 4% protein - less than enriched wheat flour, at about 10% - but has higher levels of the essential amino acids lysine and threonine.

Chip or crisp - Some recipes call for 'green,' not-yet-fully-mature fruit, at the stage when the pulp is starchy but still supple enough to be thinly sliced, as when making breadfruit chips, a popular snack wherever breadfruit is found. Air-drying the thin slices for about an hour before frying reduces their oil absorption by almost half, reducing their calorie content.

Fruit puree - The pulp of fully ripe fruit is sweet, soft, and almost runny, and can be used in fillings for sweet cream pies and other pastries.

Material uses

Livestock feed - When in abundance, ripe fruit also makes good livestock feed.

Latex - The milky latex is reportedly a good substitute for chicle, used in making chewing gum. Chicle is sourced from the Sapodilla tree (Manilkara zapota).

Roasted breadfruit

Peeled roasted breadfruit (Jamaican lunch)

General interest

During breadfruit season in the Caribbean, bakeries see a significant drop in bread sales and must plan production accordingly.

Climate

Breadfruit grows and fruits reliably in humid tropical climates, generally frost-free areas with annual lows of 18 to 25°C, annual highs of 27 to 35°C, annual rainfall of 1200 to 4500 mm, and a dry season of 5 months or less.

Breadfruit trees fail to thrive in areas where the average low of the coldest month is below 16°C (60°F).

Growing

New plants are usually started from cuttings or root suckers, as seeds are generally not produced. Circumposing (air-layering) new branches also works well.

Cuttings and suckers do best potted in a free-draining potting mix made of coarse, pH-neutral materials, with coir, river sand, and sawdust the most commonly used components. The plants are then cared for in the shade of a nursery and misted in dry weather until they are about 0.6 to 1.6 m (2 to 5 ft) tall or 5 to 9 months old. They mature quickly and start to bear fruit 3 to 5 years after planting out.

Breadfruit trees perform best on deep, fertile, free-draining clay, loam and sand soils of a moderately acid to slightly alkaline nature, generally with a pH of 6.0 to 7.5, and on sites with full sun exposure.

Problem features

Breadfruit is assessed as a low weed risk species for Hawaii by the Hawaii Pacific Weed Risk Assessment (HPWRA) project. No records appear to exist of it as a weed or invasive species anywhere, despite its introduction long ago in regions outside its native range.

Fully ripe breadfruit detach from the tree and fall to the ground, where they splatter, creating a sticky, messy litter, as do the fallen leaves.

Books

• Adams, C. D. 1972, Flowering plants of Jamaica, University of the West Indies, Mona, Greater Kingston

• Allen, B. M. 1967, Malayan fruits : an introduction to the cultivated species, Donald Moore Press, Singapore

• Elevitch, C. R. & Thaman, R. R. 2011, Specialty crops for Pacific islands, 1st ed, Permanent Agriculture Resources, Hawaii

• Fellows, P. 1997, Traditional foods : processing for profit, Intermediate Technology, Technical Centre for Agricultural and Rural Co-operation, London

• Francis, J. K. and Liogier, H. A. 1991, Naturalized exotic tree species in Puerto Rico, General technical report SO-82, USDA Forest Service, Southern Forest Experiment Station, New Orleans

• Francis, J. K. et al. 2000, Silvics of Native and Exotic Trees of Puerto Rico and the Caribbean Islands, Technical Report IITF-15, USDA Forest Service, Rio Piedras, Puerto Rico

• Jensen, M. 1999, Trees commonly cultivated in Southeast Asia : an illustrated field guide, 2nd ed., Food and Agricultural Organisation of the United Nations (FAO) Regional Office for Asia and the Pacific (RAP), Bangkok

• Macmillan, H. F. 1943, Tropical planting and gardening : with special reference to Ceylon, 5th ed, Macmillan Publishing, London

• Mollison, B. 1993, The permaculture book of ferment and human nutrition, Tagari Publications, Tyalgum, New South Wales

• Morton, J. F. & Dowling, C. F. 1987, Fruits of warm climates, Creative Resources Systems, Winterville, North Carolina

• Page, P. E. 1984, Tropical tree fruits for Australia, Queensland Department of Primary Industries (QLD DPI), Brisbane

• Perry, F. & Hay, R. 1982, A field guide to tropical and subtropical plants, Van Nostrand Reinhold Company, New York

• Queensland Department of Primary Industries and Fisheries (QLD DPI) 2008, Queensland tropical fruit : the healthy flavours of North Queensland, Brisbane

• Selvam, V. 2007, Trees and shrubs of the Maldives, Food and Agriculture Organisation (FAO) RAP publication (Maldives), Thammada Press Company Ltd., Bangkok

• Van Wyk, B. E. 2005, Food plants of the world: an illustrated guide, 1st ed., Timber Press, Portland, Oregon

• Wenkam, N.S. 1983 to 1990, Foods of Hawaii and the Pacific Basin (5 volumes), College of Tropical Agriculture and Human Resources, University of Hawaii, Honolulu

Articles, Journals, Reports and Working Papers

• Hamilton, R.A. 1987, Ten tropical fruits of potential value for crop diversification in Hawaii, Research Extension Series : RES-085, University of Hawaii, Honolulu

• International Plant Genetic Resources Institute (IPGRI) 1996 to 1998, Promoting the conservation and use of underutilized and neglected crops (Series of 24 publications), IPGRI, Rome

• Subhadrabandhu, S. 2001, Under-utilized tropical fruits of Thailand, Food and Agriculture Organisation of the United Nations (FAO), Regional Office for Asia and the Pacific (RAPA), Bangkok

• Watson, B.J., & Moncur, M. 1985, Guideline criteria for determining survival, commercial and best mean minimum July temperatures for various tropical fruit in Australia (Southern Hemisphere), Department of Primary Industries Queensland (DPI QLD), Wet Tropics Regional Publication, Queensland

• Wenkam N.S. & Miller C.D. 1965, Composition of Hawaii fruits (Bulletin 135), University of Hawaii, Honolulu