BUCHI offers different types of catalyst tablets for performing the standard Kjeldahl method. The Kjeldahl Tablet “Titanium” contains copper sulfate, titanium oxide and potassium sulfate. The tablet “Missouri” contains copper sulfate and potassium sulfate and the tablet “ECO” consists of a very low content of copper sulfate and potassium sulfate . In this Short Note, milk was selected as sample material. The main focus of the experiments was to determine the individual behaviour of the different catalysts and to find out more about their influence on the total digestion time and the results. To see all results please refer to Application Note 078/2012.