Mycobiota and mycotoxins in malted barley and brewer’s spent grain from Argentinean breweries

Abstract

To evaluate mycobiota and aflatoxins B(1) (AFB(1)), B(2) (AFB(2)), G(1) (AFG(1)), G(2) (AFG(2)) and fumonisin B(1) (FB(1)) contamination in different malted barley types and brands and brewer's grain collected from a major Argentinean brewery. Total fungal counts were performed using the plate count method. Aflatoxin B(1), AFB(2), AFG(1), AFG(2) and Zearalenone (ZEA) analyses were performed by thin-layer chromatography (TLC). Fumonisin B(1) was determined by HPLC. Eighty-three percentage of the malted barley (100% M1, 50% M2 and 100% M3) and 61% of brewer's grain samples had a count >1 × 10(4) CFU g(-1). Yeasts were isolated from all malt and brewer's grain samples. Genera containing some of the most important mycotoxin producer species--Fusarium ssp., Aspergillus ssp., Penicillium ssp. and Alternaria ssp.--were isolated from the analysed samples, along with other environmental saprophytic fungi such as Geotrichum ssp., Mucorales and Cladosporium ssp. All samples were contaminated with 104-145 μg kg(-1) FB(1). Eighteen per cent of brewer's grain samples were contaminated with 19-44.52 μg kg(-1) AFB(1). Aflatoxin B(2), AFG(1), AFG(2) and ZEA were not detected in any of the analysed samples. Fungal and mycotoxin contamination in malt and brewer's grain is an actual risk for animal and human health. This study may be useful for assessing the risk of mycotoxins in Argentinean beers and especially in animal feeds.