ABOUT COPPER CONTENT OF CHEESES

A method for determination of copper in milk and milk products was developed using 1.5-diphenylcarbazone as reagent, which makes it possible to determine relativly small copper traces (0,04 μg/ml) with sufficient acuracy (mean error: ± 4.5-2.5%) after wet digestion of the organic matter with high selectivity. By means of this quantitative method the copper content of different cheeses and cheese varieties was determined and the results read as follows: 1. The mean copper content of different cheeses and cheese varieties is 0.56 mg/kg (variation: 0.2-3.4 mg/kg, Gauss-distributionprofile 1st degree). 2. The copper contents, especially the extreme values, are characteristic for the cheeses concerned and are no accidental values. 3. Swiss cheeses show much mote copper content than other cheese varieties. The mean copper content is 17.3 mg/kg (variation: 3.8-27.0 mg/kg, Gauss-distribution-profile 2nd degree). © 1969 Springer-Verlag.