Transfer of aflatoxin B₁ and fumonisin B₁ from naturally contaminated raw materials to beer during an industrial brewing process

Abstract

The aim of this research was to determine the fate of aflatoxins (AFs) and fumonisins (FBs) naturally occurring in raw materials (maize grit and malted barley) during four industrial brewing processes. The aflatoxin B₁ (AFB₁) level in raw materials varied from 0.31 to 14.85 µg kg⁻¹, while the fumonisin B₁ (FB₁) level (only in maize grit) varied from 1146 to 3194 µg kg⁻¹. The concentration in finished beer ranged from 0.0015 to 0.022 µg l⁻¹ for AFB₁ and from 37 to 89 µg l⁻¹ for FB₁; the other aflatoxins and fumonisin B₂ were not found in beer samples. The average percentage of toxins recovered in finished beer, referring to the amounts contained in raw materials, were 1.5% ± 0.8% for AFB₁ and 50.7% ± 4.7% for FB₁. These results were mainly due to the different solubility of the two mycotoxins during the mashing process. If raw materials comply with the limits fixed by European Commission Regulations, the contribution of a moderate daily consumption of beer to AFB₁ and FB₁ intake does not contribute significantly to the exposure of the consumer.

Keywords:

• high-performance liquid chromatography (HPLC)
• liquid chromatography/mass spectrometry (LC/MS)
• aflatoxins
• fumonisins
• beer

Acknowledgements

The authors thank Roberto Pastori, President of the Italian Association for Food Protection and Environmental Hygiene, for funding this study.