Brazil nuts are edible seeds of the brazil nut tree (Bertholletia excelsa).
The Brazil nut tree is the only species in the monotypic genus Bertholletia.
It occurs as scattered trees in large forests on the banks of the Amazon River, Rio Negro, Tapajós, and the Orinoco.
The Brazil nut tree has a lifespan of 500 years or more, and according to some authorities often reaches an age of 1,000 years.
The Brazil nut tree is a large tree, reaching 50 meters (160 feet) tall and with a trunk 1 to 2 meters (3.3 to 6.6 feet) in diameter, making it among the largest of trees in the Amazon rainforests.
The stem is straight and commonly without branches for well over half the tree’s height, with a large emergent crown of long branches above the surrounding canopy of other trees. The bark is grayish and smooth.
The leaves are dry-season deciduous, alternate, simple, entire or crenate, oblong, 20 to 35 centimeters (8-14 inches) long and 10 to 15 centimeters (4-6 inches) broad.
The flowers are small, greenish-white, in panicles 5 to 10 centimeters (2-4 inches) long; each flower has a two-parted, deciduous calyx, six unequal cream-colored petals, and numerous stamens united into a broad, hood-shaped mass.
Brazil nut trees produce fruit almost exclusively in pristine forests, as disturbed forests lack the large-body bees that are the only ones capable of pollinating the tree’s flowers. The fruit takes 14 months to mature after pollination of the flowers. The fruit itself is a large capsule 10–15 centimeters (3.9–5.9 inches) in diameter, resembling a coconut endocarp in size and weighing up to 2 kilograms (4.4 pounds).
The fruit has a hard, woody shell 8 to 12 millimeter (0.31 to 0.47 inches) thick, which contains 8 to 24 triangular seeds 4 to 5 centimeters (1.5-2 inches) long (the “Brazil nuts”) packed like the segments of an orange.
A mature tree will produce more than 300 fruits, which ripen and fall to the ground from January to June. The pods are harvested from the forest floor, and the seeds are taken out, dried in the sun, and then washed and exported while still in their shells. The brown shell is very hard and has three sides.
Brazil nut is not a true nut in the botanical sense, but only in the culinary sense.
Similar to the specific needs of the Brazil nut tree’s flower to pollinate, another key process in the tree’s life cycle is heavily dependent on another of the rainforest’s creatures. Under natural conditions there are only a few animals with the ability to access the tree’s seeds and help disperse them throughout the forest. Typically, the most important of these animals is the agouti.
Brazil nuts are primarily harvested in the wild by local people. Many forest-based communities depend on the collection and sale of Brazil nuts as a vital and sustainable source of income, and the sweet nuts provide protein and calories for tribal, rural, and even urban Brazilians.
Despite their name, the most significant exporter of Brazil nuts is not Brazil but Bolivia, where they are called castañas o nuez de Brasil. In Brazil, these nuts are called castanhas-do-pará (literally “chestnuts from Pará”), but Acreans call them castanhas-do-acre instead. Indigenous names include juvia in the Orinoco area.
Around 25,000 metric tons of Brazil nuts are harvested each year, of which Bolivia accounts for about 50%, Brazil 40%, and Peru 10%. In 1980, annual production was around 40,000 tons per year from Brazil alone, and in 1970, Brazil harvested a reported 104,487 tons of nuts.
There are 656 calories in 100 grams (3.5 ounces) of Brazil nuts.
Brazil nuts are are 14% protein, 12% carbohydrate, and 66% fat by weight; 85% of their calories come from fat.
Brazil nuts are high in calories, vitamins, minerals and antioxidants. These creamy nuts are an excellent source of B complex vitamins like thiamin, riboflavin, pantothenic acid, niacin, folate and pyridoxine. It contains minerals like manganese, selenium, potassium, calcium, iron, phosphorus and zinc. It also contains Vitamin E and Vitamin C.
Some of the health benefits of Brazil nuts include a healthy heart, their ability to aid in skin care and reduce the signs of aging, balance hormone function and weight loss. These nuts also improve the immune system, stimulate growth and repair, improve the digestive process, lower risk of cancer, and boost male fertility.
Brazil nuts are eaten as they are or as part of confectionary or baked goods. They are one of the world’s major commercial nuts.
Brazil nut oil is produced from the seed. As well as its food use, Brazil nut oil is also used as a lubricant in clocks, for making artists’ paints, and in the cosmetics industry.
The lumber from Brazil nut trees is of excellent quality, but logging the trees is prohibited by law in all three producing countries (Brazil, Bolivia and Peru). Illegal extraction of timber and land clearances present a continuing threat.
Brazil nut trees are some of the most valuable non-timber products in the Amazon but are extremely sensitive to deforestation, because of their complex ecological requirements.
There has been a long history of extraction and collection of Brazil nuts from the rainforest of Bolivia and Brazil. In fact, since as early as 1633 Brazil nuts have been exported to Europe.
In North America, Brazil nuts are sometimes known by the epithet “nigger toes,” though the term has fallen out of favor as public use of the racial slur became increasingly unacceptable by the 1960s. They can be seen being sold in a market under this name in a scene from the 1922 Stan Laurel film The Pest.
The “Brazil nut effect” describes the tendency of the larger items to rise to the top of a mixture of items of various sizes but similar densities, such as brazil nuts mixed with peanuts.