Copper in milk

Haase, G. and Dunkley, W. L. 1970. Copper in milk and its role in catalyzing the development of oxidized flavors. Milchwissenschaft 25, 656-661. 

King, R. L. 1958. Variation and distribution of copper in milk in relation to oxidized form. Ph.D. Thesis, University of California, Davis. 

King, R. L. and Dunkley, W. L. 1959B. Relation of natural copper in milk to incidence of spontaneous oxidized flavor. J. Dairy Sci. 42, 420-427. 

Koops, J. 1969. The effect of the pH on the partition of natural and added copper in milk and cream. Neth. Milk Dairy J. 23, 200-213. 

Samuelsson, E. G. 1967. The distribution of copper in milk with some aspects on oxidation reactions of the milk lipids. Berlingska Boktryckeriet, Lund. (English). 

Samuelsson, E. G. 1970. The migration of copper in milk with change of temperature and addition of some chelating compounds. Milk Dairy Res. (Alnarp) Report no. 77, 5-22. 

S. Arpadjan, D. Stojanova, Application of detergents to the direct determination of iron, zinc, and copper in milk by means of flame atomic-absorption spectrophotometry, Fresenius J. Anal. Chem., 302 (1980), 206. 

The endogenous copper in milk is derived via the bloodstream from the cow s feed (Haase and Dunkley, 1970). ft is unclear to what extent the copper content of the feed influences the copper content of milk (Mulder et al., 1964 Riest et al., 1967 Dunkley et al., 1968a). However, the total level of endogenous copper in milk does not appear to be the key factor in spontaneous oxidation. King and Dunkley (1959b) and Samuelsson (1966) reported that oxidation may occur irrespective of copper content above a threshold value of 0.06 pg/kg. 

The mechanism(s) by which Xanthine oxidoreductase exerts its prooxidant effect(s) is not fully understood. Hydrogen peroxide, resulting from oxidation of a suitable substrate by Xanthine oxidoreductase, could oxidize milk lipids. However, normal milk contains little or no substrate for the enzyme. A possible mechanism involving interaction between native and denatured Xanthine oxidoreductase in MFGM and lactoperoxidase or copper in milk serum has been proposed (Hill, 1979 Allen and Wreiden, 1982b). 

FDA approved for orals SARA reportable Japan approved (0.6 mg/L as copper in milk) BP, EP compliance... 

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