Inactivation of Aflatoxin M₁ in Milk Using Hydrogen Peroxide and Hydrogen Peroxide plus Riboflavin or Lactoperoxidase

Use of hydrogen peroxide (H₂O₂), H₂O₂ plus riboflavin (Rib.) and H₂O₂ plus lactoperoxidase (LPO) to inactivate aflatoxin M₁ (AFM₁) in naturally contaminated raw whole milk was examined. Effectiveness of treatments was evaluated by determining percent of AFM₁ inactivation, using thin-layer chromatography and fluorodensitometry. Inactivation values ranged from 0 to 98%. Maximum inactivation (98%) was obtained using 1% H₂O₂ plus 0.5 mM Rib. (30°C, 30 min) followed by heating at 63°C for 30 min. Eighty-five percent of measurable AFM₁ was eliminated when 5 units of LPO plus 0.1% H₂O₂ (4°C for 3 d) were used. Singlet oxygen and/or hypochlorous acid are two reactive species that may be involved in mechanisms responsible for inactivation of AFM₁.