[Distribution of aflatoxin M1 in whey and curd during cheese processing (author's transl)].

In model experiments on the distribution of aflatoxin M1 in whey and curd, the influence of the different processing steps was investigated. Taking the same weight ratio between whey and curd, the following results were obtained: a) The aflatoxin M1-distribution in whey and curd was not changed with increasing amounts of rennet, thus decreasing the renneting time at constant renneting temperatures. b) With increasing renneting temperatures, however, the toxin's percentage in the curd decreased at constant amounts of rennet, whereas the whey's content remained stable. For the commonly used temperature variations between 28 and 35 degrees C, the toxin content of the cheese varied in the range of about 12%. c) Processing of curd by acidification with different organic acids at constant temperatures did not show any change in the aflatoxin M1 distribution as compared to rennet coagulation. d) Curd processing by means of starter cultures led to a decrease in the aflatoxin M1 in curd only at higher temperatures; the toxin's percentage in whey remained practically the same. e) Washing of the curd with the 2 1/2 volumes of water decreased the aflatoxin M1 content of cheese by 22%.