The Effect of Ozone on Aflatoxin M₁, Oxidative Stability, Carotenoid Content and the Microbial Count of Milk

ABSTRACT

In the current investigation, attempts were made to determine if ozone treatment can affect the aflatoxin M₁ (AFM₁) content of milk. Aflatoxin M₁ by a pre-determined concentration of 0.56 μg/Kg was added to milk. Milk samples, were then exposed to gaseous ozone (80 mg/min) in containers for durations of 0, 0.5, 1, 2, 5 and 10 min. The longer exposure time to ozone was more efficient in breaking down the AFM₁ in milk. Results indicated that AFM₁ was reduced by 50%, when milk was ozonated at for 5 min. The pH and oxidation value of milk did not change significanty as a result of the treatments. The β-carotene content was significantly reduced and the total microbial count in milk decreased parallel to the longer exposure time. Also, it was through this longer exposure time by ozone that the L* values of milk increased significantly (p < 0.05), while the b* values significantly decreased. To the best of our knowledge, this is the first study that uses ozone to degrade AFM₁ in milk.

KEYWORDS:

• Ozone
• Aflatoxin M₁
• β-carotene Milk
• Physicochemical Properties

Funding

Authors are grateful to Vice-Chancellery of Research and Technology, Shiraz University of Medical Science, Shiraz, Iran for funding the research (project no. 93-01-87-8534).