Bertholletia excelsa Humb. & Bonpl. - Lecythidaceae - Brazilnut, Paranut, Castanheiro do Para (braz.), Paranuss (-Baum)
Large tree, up to 50m tall, of the Amazon rainforest (Brazil, Bolivia, Colombia, Venezuela, Ecuador, Peru); bark grayish, smooth; leaves dry-season deciduous, alternate, oblong, 20-35cm long; flowers in panicles, small, greenish-white; fruit a large spherical woody capsule, 10-15cm in diam., containing 8-24 triangular seeds 4-5cm long („Brazil nuts“).
„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 seeds 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…
Brazil nuts are perhaps the richest dietary source of selenium, with a one-ounce (28 g) serving of 6 nuts supplying 774% DV. This is 10 times the adult U.S. Recommended Dietary Allowance, more even than the Tolerable Upper Intake Level, although the amount of selenium within batches of nuts varies greatly.“ https://en.wikipedia.org/wiki/Brazil_nut
The Brazil nut is by far the most economically important Neotropical Lecythidaceae, but several other species have edible seeds like the members of the sapucaia group of Lecythis (L.pisonis Cambess., L.ampla Miers., L. lanceolala Poir., and L.zabucaja Aubl.). L.pisonis (sapucaia) of eastern extra-Amazonian Brazil and Amazonia possesses seeds equally as delicious as the Brazil nut.
„Lecythis minor Jacq. of northern Colombia and northwestern Venezuela, and L. ollarla Loefl. of the llanos of Venezuela, which have edible seeds, unfortunately accumulate toxic levels of selenium when grown on certain soils. Consumption of too many seeds with high selenium may result in nausea and hair and fingernail loss. Above-nonnal accumulations of barium and high incidences of radioactivity have been registered for the seeds of Berlhollelia excelsa. However, no adverse effects on human health have been documented as the result of eating Brazil nut seeds.“
[Taxonomy, ecology, and economic botany of the Brazil nut (Bertholletia excelsa Humb. and Bonpl.: Lecythidaceae)., Mori, S.A., Prance, G.T., Advances in Economic Botany, 8, 1990, 130-150]
Mean oil content in the Brazilnut kernel was 68.5%. Fatty acids included palmitic acid (C16:0) 15.4%, stearic acid (C18:0) 12.8%, oleic acid (C18:1) 31.9%, and linoleic acid (C18:2) 39.1%.
[Brazil nut (Bertholletia excelsa HBK) seed kernel oil: characterization and thermal stability., Neto, V. Q., Bakke, O.A., Ramos, C.M.P., Bora, P.S., Letelier, J.C., Conceição, M.M., Revista de biologia e farmácia, 3(1), 2009, 33-42] http://sites.uepb.edu.br/biofar/download/v3n2-2009/04-BRAZIL_NUT.pdf
Studies suggests that humans distributed Brazil nut widely during the Holocene, „…which is strongly supported by the distribution of castanhais and the lack of old growth Brazil nut in some areas, such as part of the municipality of Manaus and much of the Juruá River basin. Along the Purus River, in southern Amazonia,
several populations have quite large seeds, suggesting incipient domestication.“
[Origin and domestication of native Amazonian crops., Clement, C. R., de Cristo-Araújo, M., Coppens D’Eeckenbrugge, G., Alves Pereira, A., Picanço-Rodrigues, D., Diversity, 2(1), 2010, 72-106] http://www.mdpi.com/1424-2818/2/1/72/htm
By monitoring of the gases that evolved during roasting of Brazil nuts, pyrrole, furfural, 2-furanmethanol, 4H-pyran-4-one, (E,Z)-2,4-decadienal and (E,E)-2,4-decadienal showed prominent signals. Like other roasted nuts (almond, cashew, hazelnut, peanut, pecan, pine nut and walnut), gases also contained acetic acid, methylpyrazine, 2,5-dimethylpyrazine, and 2,5-dimethyl-4-hydroxy-3(2H)-furanone.
[Fischer, Michael, et al. „Evolution of Volatile Flavor Compounds During Roasting of Nut Seeds by Thermogravimetry Coupled to Fast-Cycling Optical Heating Gas Chromatography-Mass Spectrometry with Electron and Photoionization.“ Food Analytical Methods 10.1 (2017): 49-62]
Bertholletia excelsa; Martius, C., Eichler, A.G., Urban, I., Flora Brasiliensis, vol.14(1), f.18,2, t.60 (1858)