4,058 research outputs found
Public perceptions of hazards associated with Brazil nuts (Bertholletia excelsa) : evaluation of risk within an European context
One of the most important economic plants of the Amazon is the Brazil nut (Bertholletia
excelsa). Brazil nuts for international trade are mainly obtained from wild collection rather than
from plantations, often cited as one of the most important products of extractive reserves in
Amazonia. The European Commission (2003/493/EC) 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. This may have a negative impact on the
Brazilian exports of shelled Brazil nuts, due to possible public awareness. The aim of the
present research is to assess public perceptions regarding Brazil nuts and to contrast these
with other nuts in general through the use of the Portuguese version of the Perceived Food
Risk Index (PFRI). A sample of 418 consumers was drawn through a door-to-door interview using a random route walk procedure and following a quota sampling controlled for sex, age and location. Consumers
were asked to choose the most relevant quality and preservation characteristics and to identify
their consumption patterns for Brazil nuts and for nuts in general. Risk perception was
evaluated over ten risk characteristics, for each of the following hazards: i) aflatoxins; ii)
biological contaminants; iii) organoleptic changes; iv) fragments and strange bodies and v)
microbial contamination. Additionally, subjects were asked to rate the probability of each hazard
occurring in Brazil nuts or in nuts in general. Results show high consumptions of nuts in general, and a reduced consumption of Brazil nuts, although with low differences on the dimensions of risk perception. Concluding, this work adds to knowledge about the perceptions of risk connected to Brazil nuts consumption, namely that consumers perceive Brazil nuts as safe as nuts in general
Medicinal Chemistry of Brazil Nuts: An Overview
Brazil nuts are very consumed in the North of Brazil as well in other regions. Those nuts are rich in mono and polyunsaturated fatty acids, as well as essential and non-essential aminoacid residues, selenium, tocopherols and phytosterols. Although some studies pointed out some protective effect of Brazil nuts against cancer, in fact the best evidence supports cardiometabolic protection by regular ingestion of 1 nut per day
Physical properties of Brazil nuts.
The Brazil-nut, also known as Para-nut, is widely used as food and in cosmetic industries. The seeds are rich in lipids and protein, and also present a considerable amount of selenium. Limited research has been conducted on postharvest of the Brazil nut, being an important information to design equipment related to aeration, drying, storage and transportation steps. Thus, the objective of this study was to determine the physical properties of the Brazil-nut with and without tegument. The dimensions found for the almonds with tegument were 39.35 mm in the X axis, 24.19 mm in the Y axis, and 17.88 mm in the Z axis. However for the almond without tegument the values were 31.05 mm in X, 14.38 in Y and 15.91 mm in Z axis. The sphericity was 66.40% and 51.59% for the kernels with and without seed tegument respectively. The kernels with and without tegument presented sphericity of 63.00% and 47.72% respectively. The mass of 1000 almonds was 6.13 kg for almond with teguments and 3.18 kg for almonds without teguments. Specific mass of 0.947 g.cm-3 and 1.003 g.cm-3 for the kernels with and without tegument, coupled with a porosity of 46.88% and 37.60% and, resulting on a bulk density of 0.504 g.cm-3 and 0.626 g.cm-3 for almonds with and without teguments respectively. Finally, the angle of repose for the kernels with teguments was 36.37°. A castanha-do-brasil, também conhecida como castanha-do-pará, é muito utilizada na alimentação humana e na indústria cosmética. As sementes são ricas em lipÃdeos e proteÃnas, apresentando ainda uma quantidade considerável de Selênio. Poucas pesquisas vêm sendo realizadas na pós-colheita do produto, sendo as propriedades fÃsicas importantes para o desenvolvimento de equipamentos relacionados à aeração, secagem, armazenamento e transporte de produtos. Assim, neste trabalho, teve-se por objetivos: determinar as propriedades fÃsicas da castanha-do-brasil com e sem tegumento. O tamanho para as amêndoas com tegumento, foi de 39,35 mm no eixo X, 24,19 mm no eixo Y e 17,88 mm no eixo Z; já para a amêndoa sem tegumento os valores foram de 31,05 mm em X, 14,38 mm em Y e 15,91 em Z. A esfericidade foi de 66,40% e 51,59%, para as amêndoas com e sem tegumento, respectivamente. 63,00% e 47,72% foram os valores de esfericidade encontrados para as amêndoas com e sem tegumento, respectivamente. A massa de 1.000 amêndoas foi de 6,13 kg para a amêndoa com tegumento e de 3,18 kg para amêndoas sem tegumento. Valores de massa especÃfica de 0,947 g.cm-3 e de 1,003 g.cm-3 para as amêndoas com e sem tegumento, associados a uma porosidade de 46,88% e 37,60%, produziram uma massa especÃfica aparente de 0,504 g.cm-3 e de 0,626 g.cm-3. Finalmente, o ângulo de repouso para as amêndoas com tegumento foi de 36,37°
Mycobiota predominant and aflatoxins content in shell and shelled Brazil nuts
Brazil nuts (Bertholletia excelsa Humb. and Bonpl.) are an important product of the Brazilian Amazon. Currently, its
marketing is compromised by the high incidence of aflatoxins (AF). The most known naturally occurring AF are
named AFB1, AFB2, AFG1, and AFG2. This study aimed to identify the potentially aflatoxigenic mycobiota
associated with shelled Brazil nuts and with the shells, and to determine which one of these fractions contributes to
aflatoxins (AF) contamination, since that official method use integral Brazil nuts samples to AF test. Samples of
Brazil nuts were collected from the agro forestry system production area in Amazonian rain forest, in Brazil. These
samples were split in shells and shelled nuts, and the total count of Aspergillus spp. was analysed after sanitation
(sodium hypochlorite 1% / 10 minutes) and without sanitation, by plating AFPA medium, for 7 days, at 25 °C. The
isolates identified as Aspergillus section Flavi were plated in YES medium (5days at 25°C) for determination of the
aflatoxigenic potential by agar plug technique. To analyze AF, 500 g samples were milled and were extracted with
chloroform. The chromatographic analysis was performed by HPLC–FD system in an isocratic mode [Waters pump
W600, Waters module autosampler W717, Fluoresce detector W2475 and column Waters X-Terra (4.6x150mm and
5μm -- RP18)]. The mobile phase was water milli-Q/acetonitrile/methanol (600:150:150 v/v) and the injected volume
was 5μL both to standards and samples. The average incidence of infection from Aspergillus spp. in sections Flavi,
Nigri and Circumdati were 48%, 8% and 1%, respectively. The sanitization treatment reduced the fungi counts.
There were AF production by fungi isolated from both types of samples, 30% of the samples were positive for AFB1,
AFB2, AFG1 and AFG2 and 23.8% produced AFB1, AFB2, and AFG1. Concerning the Brazil nuts AF analysis, it was
observed that the concentration of AFB1 and AFG1 obtained were higher than AFB2 and AFG2. The AFB1 content
was 35.281 and 1.782 μg/Kg in shelled Brazil nuts and shells, respectively. AFB2 and AFG2 were detected only in
shelled samples. The HPLC-FD presented limits of detection (LOD) and quantification (LQ) of 0.2 and 0.4 μg/kg,
respectively
Are all Brazil nuts selenium-rich?
Editores: Gary S. Banuelos, Zhi-Qing Lin, Milton Ferreira Moraes, Luiz Roberto Guimarães Guilherme, Andre Rodrigues dos Reis
Aspergillus bertholletius sp. nov. from Brazil Nuts
During a study on the mycobiota of brazil nuts (Bertholletia excelsa) in Brazil, a new Aspergillus species, A. bertholletius, was found, and is described here. A polyphasic approach was applied using morphological characters, extrolite data as well as partial β-tubulin, calmodulin and ITS sequences to characterize this taxon. A. bertholletius is represented by nineteen isolates from samples of brazil nuts at various stages of production and soil close to Bertholletia excelsa trees. The following extrolites were produced by this species: aflavinin, cyclopiazonic acid, kojic acid, tenuazonic acid and ustilaginoidin C. Phylogenetic analysis using partial β-tubulin and camodulin gene sequences showed that A. bertholletius represents a new phylogenetic clade in Aspergillus section Flavi. The type strain of A. bertholletius is CCT 7615 ( = ITAL 270/06 = IBT 29228)
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Social impact of ethical and conventional brazil nut trading on forest-dependent people in Peru
This study compares the impact of conventional and ethical international export of brazil nuts on the livelihoods of forest dependent people in order to identify the potential of ethical trade to improve those livelihoods
Microbiological quality of Brazil nuts milk submitted to different dehulling methods.
Bertholletia excelsa Bonpl populaly known as Brazil nut, is considered one of the noblest species of the Amazon rainforest, being found throughout this territory. Its fruit represents a high economic value due to its use in both human and animal feeding, presenting about 60 to 70% of lipids, polyunsaturated fatty acids and 15 to 20% of protein. There are many uses of Brazil nuts, and the "milk" extracted from the nuts, is usually consumed pure and used by the natives as typical food. Due to the high content of unsaturated fatty acids in its composition, the nuts becomes very perishable, due oxidative processes, reduction of nutritional value, appearance of smell and rancid flavor, leading to a product with low quality, besides the susceptibility to colonization by pathogenic microorganisms due poorly handled. The process for obtaining Brazil nuts milk involves the stages of degumming of the nuts, extraction, separation of the insoluble residue, formulation and packaging. The most common form of degumming is manual. The objective of the work was to evaluate the microbiological quality of Brazil nuts and its milk obtained through the processes of manual or NaOH dehulling. The count of aerobic bacteria in the standard agar for counting (PCA), total coliforms and E. coli, presence of Salmonella sp., and counting of molds and yeasts using Potato Dextrose Agar (PDA) were counted
Determination and fractionation of barium in Brazil nuts
Several sample preparation strategies were employed for determination and fractionation of barium in Brazil nuts using measurements by graphite furnace atomic absorption spectrometry (GF AAS) and inductively coupled plasma optical emission spectrometry with axial view (ICP OES). This food is widely consumed because of its nutritional value and good taste. The chemical analysis of Brazil nuts is not trivial due to their complex matrix. The fractionation of barium in Brazil nuts was studied owing to the toxicity of this element and the strong correlation between chemical form and absorption. Total concentrations of barium varied from 860 to 2084 mg kg-1. Sequential extractions were performed based on solubility in different media and also according to lipids, proteins and low molecular weight fractions (LMW). The greatest contents of barium were determined in the LMW and in the water insoluble fractions with concentrations in the range 778 to 1606 and 551 to 1520 mg kg-1, respectively. Based on these results it can be inferred that Ba is not absorbed when Brazil nuts are ingested. Considering both the contents of barium and sulfur in different fractions and stoichiometric calculations it was also possible to assume that barium occurs mainly in the BaSO4 form. The presence of this chemical form was also confirmed by thermogravimetric measurements.Diversas estratégias para preparo de amostra, determinação e fracionamento, tais como espectrometria de absorção atômica com atomização eletrotérmica em forno de grafite (GF AAS) e espectrometria de emissão óptica com plasma acoplado indutivamente com configuração axial (ICP OES), foram empregadas para o fracionamento de bário em Castanha-do-Pará. Esse alimento é amplamente apreciado tanto pelo valor nutricional, quanto pelo sabor agradável. A análise quÃmica de Castanha-do-Pará não é trivial devido à matriz complexa. O fracionamento de bário em Castanha-do-Pará foi estudado devido à toxicidade desse elemento e a correlação entre a forma quÃmica e a absorção. Os teores totais de bário nas amostras de Castanha-do-Pará variaram entre 860 e 2084 mg kg-1. Extrações sequenciais foram feitas com base na solubilidade em diferentes meios e composição quÃmica envolvendo lipÃdios, proteÃnas e compostos de baixa massa molecular (LMW). Teores mais elevados de bário foram determinados nas frações LMW e insolúvel em água que variaram entre 778-1606 e 551-1520 mg kg-1, respectivamente. Esses resultados indicaram a indisponibilidade de bário presente nesse alimento ao organismo humano. Baseando-se nos teores de bário e enxofre nas diferentes frações e em cálculos estequiométricos para as possÃveis reações envolvidas pode-se inferir que bário se encontra principalmente na forma de BaSO4. Experimentos termogravimétricos também confirmaram essa suposição.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)Coordenadoria de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES
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