Mycotoxins and fungal metabolites in groundnut- and maize-based snacks from Nigeria

This exploratory study was aimed at investigating the spectrum of fungal metabolites in the processed food and snacks. Twenty types of snacks made separately from groundnut (n=10), maize (n=8) and a combination of groundnut and maize (n=2) were analysed for naturally occurring mycotoxins and other fungal metabolites by a liquid chromatography-tandem mass spectrometric multi-mycotoxin method. A total of 18, 21 and 32 metabolites were detected and quantified in the groundnut-, groundnut/maize- and maize-based snacks, respectively. Aflatoxins contaminated 2, 3 and 5 of the groundnut/maize-, groundnut- and maize-based snacks at concentrations up to 14, 1041 and 74 mu gkg(-1), respectively. Thus, the National Agency for Food and Drug Administration and Control (NAFDAC) recommended limit of 20 mu gkg(-1) for aflatoxins was exceeded in 6 of the 20 snacks. Fumonisins contaminated all the maize- and groundnut/maize-based snacks with higher concentrations in the maize-based snacks (mean=218.7 mu gkg(-1)) compared with the groundnut/maize-based snacks (mean=178.5 mu gkg(-1)). Up to 26 different metabolites were found to co-occur in the same samples, thus posing an additional threat to the consumers due to possible additive and/or synergistic effects.