Incidencia y niveles de micotoxinas en cebada y cereales de desayuno

Resumen

Mycotoxins are toxic secondary metabolites produced by fungal species in agricultural commodities and processed food. With regard to toxicity and occurrence, the most important mycotoxins are aflatoxins (B1, G1, B2 and G2), ochratoxin A (OTA) and to a lesser extent, trichothecenes (TRs) and zearalenone (ZEA). Aflatoxins (AFs), OTA and ZEA were determined in barley and breakfast cereals by means of UHPLC-FLD and trichothecenes were determined in barley by GC-MS. Methods were validated according to selectivity, linearity, precision and accuracy, limits of detection and quantification, stability, recovery and robustness. They have fulfilled the requirements established in the Commission Regulation (EC) Nº 401/2006. The co-occurrence of these fourteen mycotoxins has been evaluated in 123 barley samples from Navarra (Spain). Ninety-five percent of them presented detectable levels of three or more toxins; although at very low levels, far below the maximum permitted limits established by the EU. The calculated TDI values were low, except for the maximum level found for DON and T-2 + HT-2. Samples were classified according to place and year of harvest (2007 and 2008), organic or traditional farming and variety of barley, observing some differences or tendencies for each toxin. Co occurrence of AFs, OTA and ZEA in 46 breakfast cereal samples from the Spanish market have been analyzed. Samples were contaminated with AFB1, OTA and ZEA with values far below the permitted limits established by the EU. The co-occurrence of mycotoxins and the influence of some parameters (type of cereal, fiber content, and name vs. generic brand products) were studied.