Aflatoksini su mikotoksini koji nastaju pod utjecajem plijesni iz roda Aspergillus. Nekoliko je vrsta aflatoksina od kojih je najtoksičniji aflatoksin B1 (AFB1). Pod utjecajem povoljnih uvjeta vlage i temperature dolazi do proizvodnje AFB1 na žitaricama, najčešće kukuruzu. Konzumiranjem takve hrane preživači unose u organizam AFB1 koji se potom razgrađuje u aflatoksin M1 (AFM1) i izlučuje u mlijeko. Kontaminirano se mlijeko koristi u procesima proizvodnje mliječnih proizvoda. Zbog prisutnosti aflatoksina u mlijeku i mliječnim proizvodima, kako bi se zaštitili potrošači sve je veći naglasak na kontroli. EU je propisala najviše dopuštene količine (NDK) za AFM1 u mlijeku od 0,05 μg/kg te u mlijeku za dojenčad od 0,025 μg/ kg. U mliječnim proizvodima nisu propisane NDK vrijednosti za AFM1, ali neke su zemlje definirale vlastite razine. U različitim istraživanjima ispitane su vrijednosti koncentracija AFM1 u mliječnim proizvodima. Utvrđeno je da su u odnosu na mlijeko od kojeg je proizvedeno sirevi imali najviše, a jogurti najniže koncentracije AFM1. Zbog prisutnosti aflatoksina u hrani za životinje, mlijeku i mliječnim proizvodima testiraju se različite metode kojima bi se smanjila koncentracija tih toksina.; Aflatoxins are mycotoxins produced by species of the fungal genus Aspergillus. There are several types of aflatoxins, but the most toxic is aflatoxin B1 (AFB1). Different conditions (humidity and temperature) lead to the production of AFB1 on grains, especially maize. When ruminants consume contaminated feed, AFB1 enters into the gastrointestinal tract, is metabolised into aflatoxin M1 (AFM1) and secreted into milk. This contaminated milk is then used in the production of dairy products. Due to the presence of aflatoxin in milk and dairy products, control of these toxins is important for consumer protection. In the EU, the maximum residue level (MRL) of AFM1 in milk is set to 0.05 μg/kg and for infant milk to 0.025 μg/kg. However, there is no EU MRL for AFM1 in dairy products, though some countries have defined national limits. A number of studies have been carried out to determine the concentration of AFM1 in dairy products. Cheeses have the highest and yogurts the lowest concentration of AFM1, lower than the concentration in the milk from which it was produced. Due to the presence of aflatoxin in animal feed, milk and dairy products, various methods have been tested to reduce the concentrations of these toxins.