Scientific Study

External characteristics of in-shell Brazil nuts were evaluated for dimensions (length and face width); weight; chromaticity; and shell thickness. The internal characteristics evaluated were moisture content (mc); aflatoxin contamination (analyzed by LC-MS/MS); and shell/nut ratio. According to their length; Brazil nuts were classified in three groups: I; II; and III; corresponding to large; medium; and small sizes; respectively. It was possible to establish the following parameters as standards for normal/healthy nuts: length (53.2; 43.9; and 36.6 mm); weight (12.9; 8.8; and 6.3 g); and shell chromaticity components (L*; 38.3; 39.5; and 41.6; a*; 8.0; 7.9; and 7.8; and b*; 17.6; 18.0; and 18.7); for the three groups; respectively. The mean of shell thicknesses were 1.92 and 2.68 mm taken from each face and nut top. The nuts; classified as small (Group III); presented aflatoxin B1 contamination at a level of 5.62 microg/kg. The Groups shell/nut ratios were 1.2; 1.2; and 1.3 for normal whole and healthy nuts. No aflatoxin was detected in Groups I and II. The data obtained from the Brazil nut measured characteristics can help to distinguish healthy/safe and deteriorated nuts and will be useful for Brazil nut sorting and machine development.