From Cow's Milk to Cheese, Yogurt, and Labneh: Evaluating aflatoxin M fate in Traditional Lebanese Dairy Processing and the Efficacy of Regulations through a Risk Assessment Approach.

Aflatoxin M (AFM1) is a potent mycotoxin that can contaminate milk and dairy products. It is a metabolite of aflatoxin B (AFB1), which is produced by certain fungi that infect crops. In Lebanon, traditional dairy production-including various cheeses, yogurt, and Labneh-is widely practiced. However, there is limited information on how AFM1 transfers and behaves in these products. This study aimed to fill that knowledge gap by examining the transfer of AFM1 from artificially contaminated milk into traditional Lebanese dairy products, specifically Halloumi, Akkawi, double-cream, Baladiyeh cheese, yogurt, and Labneh. Milk was contaminated with a known concentration of AFM1, and the resulting dairy products were analysed for AFM1 transfer rates, focusing on the distribution between whey and curd. The study also assessed the effect of brine storage (10%) on AFM1 levels in cheese. The findings showed that the transfer of AFM1 varied depending on the processing method and type of product. Generally, whey had higher concentrations of AFM1 compared to curd. Brine storage reduced AFM1 levels in most cheese types, with the exception of double-cream cheese. Yogurt processing was found to decrease AFM1 content, while converting yogurt to Labneh resulted in an increase. This research provides valuable insights into the risk of AFM1 contamination in traditional Lebanese dairy products. Understanding the transfer and behaviour of AFM1 is essential for developing effective strategies to mitigate the risks associated with mycotoxin exposure. Accordingly, this paper also includes a risk assessment generated using the reported transfer rates that showed that dairy products produced from raw milk contaminated at 0.05 µg/L would present a high risk to the Lebanese consumer that emphasises the importance of keeping AFM1 in food at a level that is 'As Low As Reasonably Achievable' specifically in a country such as Lebanon where dairy products are highly consumed.

This study was funded by the research council of Saint-Joseph University of Beirut (USJ) – project FS 171. This work was supported by Conseil de la Recherche de l’Université Saint-Joseph de Beyrouth