369. Determination of the free amino-nitrogen of casein and of fresh and deteriorated milk protein by the Van Slyke method

Abstract

The reaction of casein and of fresh and deteriorated milk protein with nitrous acid has been followed at constant temperature for 4 hr. in the manometric apparatus of Van Slyke, and simplified procedures suggested whereby the method can be utilized for investigation of the deterioration of the protein of separated milk powder during storage.Technical assistance in this work was given by Mr L. J. Parr: The work was carried out as part of the programme of the Food Investigation Board of the Department of Scientific and Industrial Research.