[The quantitative determination of the protein content of milk by means of violet spectral photometry. 7. The milk analyzer MAG 100 (Carl Zeiss Jena GmbH)--a possibility for simultaneous measurement of protein and fat content in raw milk at the dairy farm].

A new analysing apparatus is introduced, which allows to measure protein and fat contents of milk in the dairy farm. The instrument works on the basis of ultraviolet spectral photometry. Before measuring the milk sample must be diluted with a hydrous detergent solution in the ratio 1:100 and then homogenized. Accuracy and precision of the analytic results are influenced by detergent type, the water quality of detergent solution, the detergent foam, the air content and the pH of detergent solution, the reliability of homogenizer and thermostating system, the stability of photometer and by the error of dosage. Also a milk standard was developed, which is required for daily calibration of the apparatus.