Study of binding of methyl parathion by cow's casein in model systems and in ewe's milk

The binding of methyl parathion by cow's casein, in model systems and in sheep's milk was investigated. Casein in cow's milk binds methyl parathion to a great extent. The addition of the enzyme potato acid phosphatase (PAP) in casein solutions does not affect the release of methyl parathion from casein. Storage of casein solutions or casein solutions plus PAP at 4°C for 60 days does not affect the binding of methyl parathion to casein. The data also indicate that methyl parathion binds strongly to milk proteins and/or other substances of ewe's milk.