Nuclear Magnetic Resonance Approach in Brazil Nut Oil and the Occurrence of Aflatoxins.

Abstract

Carcinogenic metabolites of fungi such as aflatoxins play a toxic role in some tree nuts and need to be monitored in their by-products, such as oil. In this context, Brazil nut (Bertholletia excelsa) oil, which is a commodity of great economic importance to Brazil, requires attention to monitor the presence of these toxic agents. Therefore, this study aimed to evaluate the presence of aflatoxins in Brazil nut oil and relate it to the presence of fatty acids in the oil as a surveillance tool for food safety. Brazil nut oil samples (n= 25) were acquired in northern Brazil as (a) non-branded products (n= 07) produced by local farmers using artisanal methods from nuts to be discarded by the industry and (b) industrialized products (n= 18). The samples were analyzed for total aflatoxin content by high-performance liquid chromatography and fatty acid content by nuclear magnetic resonance imaging. Seven (28%) samples were positive for the aflatoxin fractions (B1 + B2 + G1 + G2), ranging from undetected (<2.32) to 50.87 μg/kg. Of the aflatoxin positive samples evaluated by NMR analysis, it was not possible to state that the presence of a particular fatty acid can interfere or influence aflatoxin contamination. This was the first study with data on aflatoxin occurrence in Brazil nut oil. Nevertheless, further research is required to relate saturated or unsaturated fatty acid content with aflatoxin levels. We also suggest the implementation of systems to prevent contamination of the raw materials (seed) and detoxification of the oil to guarantee the product's safety and quality.