The Brazil Nut tree (Bertholletia excelsa) is the only species in the genus Bertholletia. It is native to South America and is among the largest trees in the Amazonian rainforest, occurring in non-flooded (terra firme) forests of the Amazon Basin and Guiana Shield. Because of the structure of the flowers, pollen is accessible only to larger bees such as Xylocopa species and female euglossines. The flowers are essentially self-sterile. The slow-developing fruit is a large, round woody capsule, 0.5 to 2.5 kg, which contains the seeds (i.e., the "brazil nuts" of commerce). Most brazil nuts in commerce are collected from wild trees, the fallen fruits being split open with an axe to reach the 10 to 25 seeds packed within like the sections of an orange. There is some risk to collectors of injury or even death from being hit on the head by falling fruit. Brazil nuts contain up to 17% protein and 65 to 70% of a monounsaturated (almost 50% aflatoxins that may be produced by certain fungi infecting brazil nuts.
- Freitas-Silva, O. and A. Venâncio. 2011. Brazil nuts: Benefits and risks associated with contamination by fungi and mycotoxins. Food Research International 44: 1434–1440.
- Haugaasen, J.M.T., T. Haugaasen, C.A. Peres, R. Gribel, and P. Wegge. 2010. Seed dispersal of the Brazil nut tree (Bertholletia excelsa) by scatter-hoarding rodents in a central Amazonian forest. Journal of Tropical Ecology 26: 251-262.
- Mabberley, D.J. 2008. Mabberley's Plant-Book, 3rd edition [2009 reprint with corrections]. Cambridge University Press, New York.
- Mori, S. 1992. The Brazil Nut Industry—Past, Present, and Future. Pp. 241-251 in Sustainable Harvest and Marketing of Rain Forest Products (M. Plotkin and L. Famolare, eds.). Island Press, Wasington, D.C. www.nybg.org/bsci/braznut/
- Paivaa, P.M., M.C. Guedesa, and C. Funia. 2011. Brazil nut conservation through shifting cultivation. Forest Ecology and Management 261: 508-514.
- Peres, C.A. and C. Baider. 1997. Seed dispersal, spatial distribution and population structure of Brazilnut trees (Bertholletia excelsa) in southeastern Amazonia. Journal of Tropical Ecology 13: 595-616.
- Peres, C.A., L.C. Schiesari, and C.L. Dias-Leme. 1997. Vertebrate Predation of Brazil-Nuts (Bertholletia excelsa, Lecythidaceae), an Agouti-Dispersed Amazonian Seed Crop: A Test of the Escape Hypothesis. Journal of Tropical Ecology 13(1): 69-79.
- Reis, M.M., A.C. Braga. M.R. Lemes, R. Gribel, and R.G. Collevatti. 2009. Development and characterization of microsatellite markers for the Brazil nut tree Bertholletia excelsa Humb. & Bonpl. (Lecythidaceae). Molecular Ecology Resources 9(3): 920-923.
- Shepard, G.H.and H. Ramirez. 2011. "Made in Brazil": Human Dispersal of the Brazil Nut (Bertholletia excelsa, Lecythidaceae) in Ancient Amazonia. Economic Botany 65(1): 44-65.
- Silvertown, J. 2004. Sustainability in a nutshell. Trends in Ecology and Evolution 19(6): 276-278.
- Vaughan, J.G. and C.A. Geissler. 1997. The New Oxford Book of Food Plants (revised and updated edition). Oxford University Press, New York.
- Wadta, L.H.O., K.A. Kainerb, C.L. Staudhammerb, and R.O.P. Serranod. 2008. Sustainable forest use in Brazilian extractive reserves: Natural regeneration of Brazil nut in exploited populations. Biological Conservation 141: 332-346.
Localities documented in Tropicos sources
Brazil (South America)
French Guiana (South America)
Guyana (South America)
Peru (South America)
Suriname (South America)
Venezuela (South America)
Bolivia (South America)
Colombia (South America)
Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.
- Forzza, R. C. & et al. 2010. 2010 Lista de espécies Flora do Brasil. http://floradobrasil.jbrj.gov.br/2010/. http://www.tropicos.org/Reference/100002289
- SPECIMEN BASED RECORD. 1986. Field Museum Type Record. http://www.tropicos.org/Reference/1104
- Killeen, T. J., E. García Estigarribia & S. G. Beck. (eds.) 1993. Guia Arb. Bolivia 1–958. Herbario Nacional de Bolivia & Missouri Botanical Garden, La Paz. http://www.tropicos.org/Reference/1000017
- Steyermark, J. 1995. Flora of the Venezuelan Guayana Project. http://www.tropicos.org/Reference/158
- Molina Rosito, A. 1975. Enumeración de las plantas de Honduras. Ceiba 19(1): 1–118. http://www.tropicos.org/Reference/866
- Funk, V. A., P. E. Berry, S. Alexander, T. H. Hollowell & C. L. Kelloff. 2007. Checklist of the Plants of the Guiana Shield (Venezuela: Amazonas, Bolivar, Delta Amacuro; Guyana, Surinam, French Guiana). Contr. U.S. Natl. Herb. 55: 1–584. http://www.tropicos.org/Reference/1033072
- Alverson, W. S., D. K. Moskovits & J. S. Shopland. 2000. Bolivia: Pando, Río Tahauamanú. Rapid Biol. Inv. 1: 1–79. http://www.tropicos.org/Reference/1018882
- Wallace, R., R. Lilian, E. Painter, D. Rumiz & J. Herrera. 2000. La Estacionalidad y el Manejo de Vida Silvestre en los Bosques de Producción del Oriente de Bolivia. Revista Boliviana Ecol. Cons. Amb. 8:65–81. http://www.tropicos.org/Reference/1028931
- Mori, S. A. & G. T. Prance. 1990. Lecythidaceae---Part II. The zygomorphic-flowered New World genera (Couroupita, Corythophora, Bertholletia, Couratari, Eschweilera, & Lecythis). Fl. Neotrop. 21(2): 1–376. http://www.tropicos.org/Reference/15863
- Brako, L. & J. L. Zarucchi. (eds.) 1993. Catalogue of the Flowering Plants and Gymnosperms of Peru. Monogr. Syst. Bot. Missouri Bot. Gard. 45: i–xl, 1–1286. http://www.tropicos.org/Reference/7728
- Hokche, O., P. E. Berry & O. Huber. 2008. 1–860. In O. Hokche, P. E. Berry & O. Huber Nuevo Cat. Fl. Vasc. Venezuela. Fundación Instituto Botánico de Venezuela, Caracas. http://www.tropicos.org/Reference/1033110
Habitat and Ecology
Evolution and Systematics
The seeds of a Brazil nut tree can survive long falls without damage due to the reinforced triple layer pod encasing them.
"To coddle fragile items, we might consider the strategies of seed helmets--nuts. The Brazil nuts in your holiday bowl were once packed in a 3-layer, highly reinforced pod that survived an 80-meter fall from the canopy. On the ground, the pod defies opening from all but its ally, the agouti, a caching rodent with strong, angled teeth." (Biomimicry Guild unpublished report)
Learn more about this functional adaptation.
The Brazil nut tree relies on the orchid bee for pollination, which in turn relies on certain species of orchids for reproduction.
"Efforts intended to create habitats are often unsuccessful. When farmers tried to grow Brazil nuts commercially, they cut down tropical rainforest and planted Brazil nut trees in rows, plantation-style. But these trees depend on orchid bees for pollination, and without the natural orchids of the rainforest, there were not enough orchid bees in the plantations. Hence no nuts were produced." (Forsyth 1992:41)
Learn more about this functional adaptation.
- Forsyth, A. 1992. Exploring the World of Insects: The Equinox Guide to Insect Behaviour. Camden House.
Molecular Biology and Genetics
Barcode data: Bertholletia excelsa
Statistics of barcoding coverage: Bertholletia excelsa
Public Records: 1
Specimens with Barcodes: 8
Species With Barcodes: 1
IUCN Red List Assessment
Red List Category
Red List Criteria
- Needs updating
Brazil nut tree
The Brazil nut tree is the only species in the monotypic genus Bertholletia. It is native to the Guianas, Venezuela, Brazil, eastern Colombia, eastern Peru, and eastern Bolivia. It occurs as scattered trees in large forests on the banks of the Amazon River, Rio Negro, Tapajós, and the Orinoco. The genus is named after the French chemist Claude Louis Berthollet.
The Brazil nut is a large tree, reaching 50 m (160 ft) tall and with a trunk 1 to 2 m (3.3 to 6.6 ft) in diameter, making it among the largest of trees in the Amazon rainforests. It may live for 500 years or more, and according to some authorities often reaches an age of 1,000 years. 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, 20–35 cm (7.9–13.8 in) long and 10–15 cm (3.9–5.9 in) broad. The flowers are small, greenish-white, in panicles 5–10 cm (2.0–3.9 in) long; each flower has a two-parted, deciduous calyx, six unequal cream-colored petals, and numerous stamens united into a broad, hood-shaped mass.
In Brazil, it is illegal to cut down a Brazil nut tree. As a result, they can be found outside production areas, in the backyards of homes and near roads and streets. The fruit containing nuts is very heavy and rigid, and it poses a serious threat to vehicles and persons passing under the tree. At least one person has died after being hit on the head by a falling fruit. Unlike real nuts, the density of the fruit makes them sink in fresh water, which can cause clogging of waterways in riparian areas.
Brazil nut trees produce fruit almost exclusively in pristine forests, as disturbed forests lack the large-body bees of the genera Bombus, Centris, Epicharis, Eulaema, and Xylocopa which are the only ones capable of pollinating the tree's flowers. Brazil nuts have been harvested from plantations, but production is low and is currently not economically viable.
The Brazil nut tree's yellow flowers contain very sweet nectar and can only be pollinated by an insect strong enough to lift the coiled hood on the flower and with a tongue long enough to negotiate the complex coiled flower. For this reason, the Brazil nut's reproduction depends on the presence of the orchid Coryanthes vasquezii, which does not grow on the Brazil nut tree itself. The orchids produce a scent that attracts small male long-tongued orchid bees (Euglossa spp.), as the male bees need that scent to attract females. The large female long-tongued orchid bee pollinates the Brazil nut tree. Without the orchid, the bees do not mate, and therefore the lack of bees means the fruit does not get pollinated.
The fruit takes 14 months to mature after pollination of the flowers. The fruit itself is a large capsule 10–15 cm (3.9–5.9 in) in diameter, resembling a coconut endocarp in size and weighing up to 2 kg (4.4 lb). It has a hard, woody shell 8–12 mm (0.31–0.47 in) thick, which contains eight to 24 triangular seeds 4–5 cm (1.6–2.0 in) long (the "Brazil nuts") packed like the segments of an orange.
The capsule contains a small hole at one end, which enables large rodents like the agouti to gnaw it open. They then eat some of the nuts inside while burying others for later use; some of these are able to germinate into new Brazil nut trees. Most of the seeds are "planted" by the agoutis in shady places, and the young saplings may have to wait years, in a state of dormancy, for a tree to fall and sunlight to reach it, when it starts growing again. Capuchin monkeys have been reported to open Brazil nuts using a stone as an anvil.
Despite their name, the most significant exporter of Brazil nuts is not Brazil but Bolivia, where they are called almendras. 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, and sapucaia in the rest of Brazil.
Though it is commonly called the Brazil nut, in botanical terms it is the seed from the fruit of this tree; a nut is a hard-shelled indehiscent fruit.
Brazil nuts were, in the 1960s, known by the epithet "nigger toes", though this term has fallen out of favor due to its offensiveness. They can be seen being sold in a market under this name in a scene from the 1922 Stan Laurel film The Pest.
Around 20,000 tons of Brazil nuts are harvested each year, of which Bolivia accounts for about 50%, Brazil 40%, and Peru 10% (2000 estimates). 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.
Effects of harvesting
Brazil nuts for international trade can come from wild collection rather than from plantations. This has been advanced as a model for generating income from a tropical forest without destroying it. The nuts are gathered by migrant workers known as castanheiros.
Analysis of tree ages in areas that are harvested show that moderate and intense gathering takes so many seeds, not enough are left to replace older trees as they die. Sites with light gathering activities had many young trees, while sites with intense gathering practices had hardly any young trees.
Statistical tests were done to determine what environmental factors could be contributing to the lack of younger trees. The most consistent effect was found to be the level of gathering activity at a particular site. A computer model predicting the size of trees where people picked all the nuts matched the tree size data gathered from physical sites that had heavy harvesting.
Upon harvesting and collecting the ripened cases that fall off the trees harvesters have to be cautious because they are easily heavy enough to kill a person. Fatal accidents are not uncommon among collectors – they stop work at once if the wind suddenly strengthens, because this can cause a bombardment.
|Nutritional value per 100 g (3.5 oz)|
|Energy||2,743 kJ (656 kcal)|
|- Starch||0.25 g|
|- Sugars||2.33 g|
|- Dietary fiber||7.5 g|
|- saturated||15.137 g|
|- monounsaturated||24.548 g|
|- polyunsaturated||20.577 g|
|- Tryptophan||0.141 g|
|- Threonine||0.362 g|
|- Isoleucine||0.516 g|
|- Leucine||1.155 g|
|- Lysine||0.492 g|
|- Methionine||1.008 g|
|- Cystine||0.367 g|
|- Phenylalanine||0.630 g|
|- Tyrosine||0.420 g|
|- Valine||0.756 g|
|- Arginine||2.148 g|
|- Histidine||0.386 g|
|- Alanine||0.577 g|
|- Aspartic acid||1.346 g|
|- Glutamic acid||3.147 g|
|- Glycine||0.718 g|
|- Proline||0.657 g|
|- Serine||0.683 g|
|Thiamine (vit. B1)||0.617 mg (54%)|
|Riboflavin (vit. B2)||0.035 mg (3%)|
|Niacin (vit. B3)||0.295 mg (2%)|
|Vitamin B6||0.101 mg (8%)|
|Folate (vit. B9)||22 μg (6%)|
|Vitamin C||0.7 mg (1%)|
|Vitamin E||5.73 mg (38%)|
|Calcium||160 mg (16%)|
|Iron||2.43 mg (19%)|
|Magnesium||376 mg (106%)|
|Manganese||1.223 mg (58%)|
|Phosphorus||725 mg (104%)|
|Potassium||659 mg (14%)|
|Sodium||3 mg (0%)|
|Zinc||4.06 mg (43%)|
|Link to USDA Database entry|
Percentages are roughly approximated
using US recommendations for adults.
Source: USDA Nutrient Database
Brazil nuts are 18% protein, 13% carbohydrates, and 69% fat by weight, and 91% of their calories come from fat. The fat breakdown is roughly 25% saturated, 41% monounsaturated, and 34% polyunsaturated. Due to their high polyunsaturated fat content, primarily omega-6 fatty acids, shelled Brazil nuts soon become rancid.
Nutritionally, Brazil nuts are a good source of some vitamins and minerals. A cup (133 grams) of Brazil nuts contains the vitamins thiamin (0.8 mg—55% DV) and vitamin E (7.6 mg—38% DV); minerals calcium (213 mg—21% DV), magnesium (500 mg—125% DV), phosphorus (946 mg—96% DV), copper (2.3 mg—116% DV), and manganese (1.6 mg—81%). Brazil nuts are perhaps the richest dietary source of selenium; 28 g (1 oz, 6–8 nuts) can contain as much as 544 µg. This is 10 times the adult U.S. Recommended Dietary Allowances, more even than the Tolerable Upper Intake Level, although the amount of selenium within batches of nuts varies greatly.
Recent research suggests that proper selenium intake is correlated with a reduced risk of both breast cancer and prostate cancer. This has led some health commentators and nutritionists to recommend the consumption of Brazil nuts as a protective measure. However, these findings are inconclusive. Other investigations into the effects of selenium on prostate cancer have also been inconclusive.
Brazil nuts have one of the highest concentrations of phytic acid at 2 to 6% of dry weight. Phytic acid can prevent absorption of some nutrients, mainly iron, but is also a subject of research and possibly confers health benefits. .
Despite the possible health benefits of the nut, the European Union has imposed strict regulations on the import from Brazil of Brazil nuts in their shells, as the shells have been found to contain high levels of aflatoxins, which can lead to liver cancer.
Brazil nuts contain small amounts of radium. Although the amount of radium, a radioactive element, is very small, about 1–7 pCi/g (40–260 Bq/kg), and most of it is not retained by the body, this is 1000 times higher than in other foods. According to Oak Ridge Associated Universities, this is not because of elevated levels of radium in the soil, but due to "the very extensive root system of the tree."
In the United Kingdom, Brazil nuts are the second most common cause of nut allergic reactions. There has been one known, published and confirmed case of an allergic reaction to Brazil nuts resulting from sexual transmission.
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.
Engravings in Brazil nut shells were supposedly used as decorative jewelery by the indigenous tribes in Bolivia, although no examples still exist. Because of its hardness, Brazil nut shell has often been pulverized and used as an abrasive to polish softer materials such as metals and even ceramics (in the same way as jeweler's rouge is used). A high luster could be acquired by a final application of carnauba wax, only produced in north-eastern Brazil.
The lumber from Brazil nut trees (not to be confused with Brazilwood) 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.
- Bruno Taitson (January 18, 2007). "Harvesting nuts, improving lives in Brazil". World Wildlife Fund. Archived from the original on May 23, 2008. Retrieved July 17, 2012.
- "Agricultor morre após ser atingido por ouriço de castanha, no Amazonas", Amazonas. (Portuguese)
- Nelson, B.W.; Absy, M.L.; Barbosa, E.M.; Prance, G.T. (1985). "Observations on flower visitors to Bertholletia excelsa H. B. K. and Couratari tenuicarpa A. C. Sm.(Lecythidaceae).". Acta Amazonica 15 (1): 225–234. Retrieved 2008-04-08.
- Moritz, A. (1984). Estudos biológicos da floração e da frutificação da castanha-do-Brasil (Bertholletia excelsa HBK) 29. Retrieved 2008-04-08.
- Scott A. Mori. "The Brazil Nut Industry --- Past, Present, and Future". The New York Botanical Garden. Retrieved July 17, 2012.
- Tim Hennessey (March 2, 2001). "The Brazil Nut (Bertholletia excelsa)". Archived from the original on January 11, 2009. Retrieved July 17, 2012.
- Enrique G. Ortiz. "The Brazil Nut Tree: More than just nuts". Archived from the original on July 6, 2007. Retrieved July 17, 2012.
- "Coryanthes vasquezii". Orchid Web. Retrieved July 17, 2012.
- Lingis, Alphonso (2000). Dangerous Emotions. University of California Press. p. 26. ISBN 978-0-520-22559-6. Retrieved 2009-04-08.
- Brazil, Matt (July 14, 2000). "Actually, My Hair Isn't Red". The Wall Street Journal (Dow Jones & Company, Inc.). Retrieved 2009-07-06. "Hearing angmo so often took me back to my childhood, when my friends and I used the words Jew and Gyp (the latter short for Gypsy) as verbs, meaning to cheat. At that time, in the 1960s, other racial epithets, these based on physical appearance, were commonly heard: cracker, slant-eye, bongo lips, knit-head. To digress to the ludicrous, Brazil nuts were called "nigger toes.""
- Chris Collinson; Duncan Burnett; Victor Agreda (Spring 2000). "Economic Viability of Brazil Nut Trading in Peru". Natural Resources Institute, University of Greenwich. Retrieved July 17, 2012.
- Silvertown, J. (2004). "Sustainability in a nutshell". Trends in Ecology & Evolution 19 (6): 276–201. doi:10.1016/j.tree.2004.03.022.
- "Nuts, brazilnuts, dried, unblanched". United States Department of Agriculture. Retrieved July 17, 2012.
- "Nutrition Data, Brazil Nuts 1 cup". NutritionData. Retrieved July 17, 2012.
- "Nuts, brazilnuts, dried, unblanched". USDA National Nutrient Database for Standard Reference, Release 25: Selenium, Se ( µg ) Content of Selected Foods per Common Measure. United States Department of Agriculture. p. 17. Retrieved November 6, 2012.
- Chang, Jacqueline C.; Walter H. Gutenmann, Charlotte M. Reid, Donald J. Lisk (1995). "Selenium content of Brazil nuts from two geographic locations in Brazil". Chemosphere 30 (4): 801–802. doi:10.1016/0045-6535(94)00409-N. PMID 7889353. 0045-6535.
- Klein, EA; Thompson, IM; Lippman, SM; Goodman, PJ; Albanes, D; Taylor, PR; Coltman, C (October 2001). "SELECT: the next prostate cancer prevention trial. Selenum and Vitamin E Cancer Prevention Trial.". The Journal of Urology 166 (4): 1311–1315. ISSN 0022-5347. PMID 11547064.
- Ralph W. Moss (December 10, 2001). "Selenium, Brazil Nuts and Prostate Cancer". CancerDecisions Newsletter Archive. CancerDecisions. Archived from the original on September 18, 2010. Retrieved July 17, 2012.
- Ann Kulze (October 30, 2009). "Dr. Ann's 10-Steps to Prevent Breast Cancer". About.com. Retrieved July 17, 2012.
- Peters, U; Foster, CB; Chatterjee, N; Schatzkin, A; Reding, D; Andriole, GL; Crawford, ED; Sturup, S; Chanock, SJ; Hayes, RB (January 2007). "Serum selenium and risk of prostate cancer-a nested case-control study.". The American journal of clinical nutrition 85 (1): 209–17. PMC 1839923. PMID 17209198. Retrieved July 17, 2012.
- "Commission Decision of 4 July 2003 imposing special conditions on the import of Brazil nuts in shell originating in or consigned from Brazil". Official Journal of the European Union. July 5, 2012. Retrieved July 17, 2012.
- "Brazil Nuts". Oak Ridge Associated Universities. January 20, 2009. Retrieved July 17, 2012.
- "Greenpeace Activists Trapped by Loggers in Amazon". Greenpeace. October 18, 2007. Retrieved July 17, 2012.