Mycotoxin profiling of 1000 beer samples with a special focus on craft beer

PLoS One. 2017 Oct 5;12(10):e0185887. doi: 10.1371/journal.pone.0185887. eCollection 2017.

Abstract

Currently beer is booming, mainly due to the steady rise of craft breweries worldwide. Previous surveys for occurrence of mycotoxins in beer, were mainly focussed on industrial produced beer. The present survey reports the presence of mycotoxins in craft beer and how this compares to industrial produced beer. More than 1000 beers were collected from 47 countries, of which 60% were craft beers. A selection of 1000 samples were screened for the presence of aflatoxin B1, ochratoxin A (OTA), zearalenone (ZEN), fumonisins (FBs), T-2 and HT-2 toxins (T-2 and HT-2) and deoxynivalenol (DON) using a mycotoxin 6-plex immunoassay. For confirmatory analysis, a liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed and applied. The 6-plex screening showed discrepancies with the LC-MS/MS analysis, possibly due to matrix interference and/or the presence of unknown mycotoxin metabolites. The major mycotoxins detected were DON and its plant metabolite deoxynivalenol-3-β-D-glucopyranoside (D3G). The 6-plex immunoassay reported the sum of DON and D3G (DON+D3G) contaminations ranging from 10 to 475 μg/L in 406 beers, of which 73% were craft beers. The popular craft beer style imperial stout, had the highest percentage of samples suspected positive (83%) with 29% of all imperial stout beers having DON+D3G contaminations above 100 μg/L. LC-MS/MS analysis showed that industrial pale lagers from Italy and Spain, predominantly contained FBs (3-69 μg/L). Besides FBs, African traditional beers also contained aflatoxins (0.1-1.2 μg/L). The presence of OTA, T-2, HT-2, ZEN, β-zearalenol, 3/15-acetyl-DON, nivalenol and the conjugated mycotoxin zearalenone 14-sulfate were confirmed in some beers. This study shows that in 27 craft beers, DON+D3G concentrations occurred above (or at) the Tolerable Daily Intake (TDI). Exceeding the TDI, may have a health impact. A better control of brewing malts for craft beer, should be put in place to circumvent this potential problem.

MeSH terms

  • Beer / microbiology*
  • Chromatography, Liquid
  • Limit of Detection
  • Mycotoxins / analysis*
  • Tandem Mass Spectrometry

Substances

  • Mycotoxins

Grants and funding

Our research was partially financed by the Dutch Ministry of Economic Affairs, SenterNovem and the Province of Gelderland. There was no additional external funding received for this study. Innosieve Diagnostics provided support in the form of salary for author Ronald van Doorn, whose role was limited to the collection of craft beer samples and valuable contributions to the introduction considering craft beer. Innosieve Diagnostics did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.