[Influence of raw milk processing on the aflatoxin M content of milk products (author's transl)].

Several contracdictory results in the literature lead us to the conclusion, that the influence of raw milk processing on aflatoxin content should be tested under as close as possible practical conditions. Even though storage at 5 degrees C for 1-3 days does not greatly influence aflatoxin content (11-25% reduction), this might still be important for food inspection. Although experiments on exposure to light resp. oxygen were repeated ten times, the results could not be definitely be shown as due to oxidation. Part of the contradictory literature references also in the case of freeze drying in our opinion caused by the way in which aflatoxins was added. The loss was less pronounced when milk was contaminated naturally than when it was added artificially. Heating of milk, depending on the conditions, caused a decrease of the aflatoxin-content of between 12 and 35% when making butter from naturally contaminated cream 23% (18-28%) of the aflatoxin M1 appeared in the butter, whereas the buttermilk contained the major amount of aflatoxin.