Nitrogen Factor for the Calcium Caseinate–Calcium Phosphate Complex in Milk

The casein colloid in milk contains a phosphoprotein which has the same phosphorus : nitrogen ratio for all the broad intermediate ranges of particle sizes. The purpose of this work was to determine the nitrogen factor. For many milks and many particle-size fractions, the average ratio of dry weight of calcium caseinate-calcium phosphate complex was about 6.89 1.3%, and this applies to normal milk. This factor does not apply to the largest casein colloid particles and may not apply to the smallest. Editor.