Aflatoxin M 1 in UHT milk consumed in Turkey and first assessment of its bioaccessibility using an in vitro digestion model

Abstract

Contamination of milk and dairy products with aflatoxin M 1 (AFM 1) continues to receive increased attention because of its potential health hazard to humans. The first aim of this study was to know the occurrence and levels of AFM 1 in whole UHT milk from main processors in Turkey in order to make a preliminary exposure assessment. A total of 40 milk samples were analysed for AFM 1 using high performance liquid chromatography with fluorescence detection (HPLC-FD) after immunoaffinity column clean-up. Aflatoxin M 1 was detected in 20% of samples at levels ranging from <0.004 to 0.076 ?g l -1. Only two samples contained AFM 1 above the EU limit of 0.05 ?g l -1.The second aim of this study was to determine the bioaccessibility of AFM 1 from milk using an in vitro digestion model. The bioaccessibility of AFM 1 in spiked and naturally contaminated milk samples ranged from 80.5 to 83.8% and from 81.7 to 86.3%, respectively. No difference (P > 0.05) in AFM 1 bioaccessibility was found between spiked and naturally contaminated milk samples. This study also assessed the binding of AFM 1 by six probiotic bacteria under simulated gastrointestinal conditions. A 15.5-31.6% reduction in AFM 1 bioaccessibility was observed in the presence of probiotic bacteria. Based on the results obtained in the present study, the mean daily intake of AFM 1 through milk consumption was estimated as 0.008 ng kg -1 b.w. day -1 for Turkish adults. © 2012 Elsevier Ltd.