Occurrence of the Fusarium T-2- and HT-2-toxins in oats from cultivar studies in Germany and degradation of the toxins during grain cleaning treatment and food processing

Christine Schwake-Anduschus (1) , Georg Langenkämper (1) , Guenter Unbehend (1) , Richard Diedrich (2) , Erwin Märtlbauer (2) , Klaus Münzing (1)

1 Department of Safety and Quality of Cereals
2 Department of Veterinary Sciences

For the Fusarium trichothecene mycotoxins T-2 and HT-2 a combined (T-2+HT-2) temporary Tolerable Daily Intake (tTDI) of 0.06 µg kg-1 body weight per day has been proposed at European level in 2001 (Opinion of the Scientific Committee on Food). In the near future maximum levels for these trichothecenes will be regulated by the European Commission as announced in EU (VO) 1881/2006. For the implementation of these maximum levels more data on occurrence and behaviour of T-2- and HT-2-toxins in primary agricultural products as well as during cleaning treatment and food processing are needed. In the current work we determined the T-2/HT-2 concentrations in four oat cultivars (Aragon, Dominik, Ivory, Pergamon) from 10 different agricultural sites in Germany, grown in cultivar studies in 2007. The grains were de-hulled, oat meal was prepared and bread with 20% oat meal and 80% wheat flour was baked. In the cereal processing chain, samples were taken at various steps and subsequently analysed for their T-2/HT-2 content. We employed a chromatographic system with a mass spectrometer as the detector (LC-MS) and an immunological screening method (ELISA) for T-2/HT-2 determination. Detection limits were between one and 10 µg kg-1 in different matrices. T-2/HT-2 concentrations analysed with ELISA in the available oat samples from ten different agricultural sites in Germany were between 9 and 623 µg kg-1. Median and 90th percentile were 48 and 191 µg kg-1 T-2/HT-2, respectively. One site showed six times higher T-2/HT-2 levels than the other sites, where concentrations ranged from 322 to 623 µg kg-1. In 80% of the samples the cultivars Pergamon and Ivory had the lowest concentration of T-2-and HT-2-toxins. Using LC-MS for T-2/HT-2 determination, cleaning of the raw material did not lead to significant reductions of T-2- and HT-2 levels, whereas de-hulling led to a reduction of over 90%. Boiling of oat meal produced from cleaned raw material to yield "porridge" resulted in varying T-2/HT-2 levels in experimental replicates. A major reduction of T-2/HT-2 levels in cooked porridge was not obtained. Standardized baking experiments using 20% oat meal showed that T-2-and HT-2-toxins are relatively stable during the baking process, probably due to their temperature stability.

Mots clés: Life Sciences

Christine Schwake-Anduschus, Georg Langenkämper, Guenter Unbehend, Richard Diedrich, Erwin Märtlbauer, et al.. Occurrence of the Fusarium T-2- and HT-2-toxins in oats from cultivar studies in Germany and degradation of the toxins during grain cleaning treatment and food processing. Food Additives and Contaminants, 2010, 27 (09), pp.1253-1260. ⟨10.1080/19440049.2010.487499⟩. ⟨hal-00600443⟩