Fate of aflatoxin M1 in Iranian white cheese processing

Aflatoxin M1 (AFM(1)) is an important mycotoxin frequently found in milk and dairy products. AFM(1) is a major metabolic product of Aflatoxin B, and is usually excreted in the milk and urine of dairy cattle that have consumed aflatoxin-contaminated feed. The aim of this study was to determine the AFM(1) concentration in curd and whey of Iranian white cheese. The cheese milk samples were artificially contaminated with AFM(1) in six levels (0.25, 0.5, 0.75, 1, 1.25, and 1.75 mu g L-1). Cheese was produced according to Iranian traditional recipe. AFM(1) distribution between curd, whey and cheese was determined by high performance liquid chromatography (HPLC) using immunoaffinity column clean up and florescence detection. AFM(1) was recovered in whey, curd and cheese in the concentrations of 0.43, 1.47 and 1.57 mu g L-1,respectively. The level of Aflatoxin M-1 in curd and cheese obtained 3.12- and 3.65-fold more than that in whey that shows the affinity of Aflatoxin M, to the protein fraction of milk. (C) 2008 Elsevier Ltd. All rights reserved.