Determination of calcium and magnesium in milk by complexometric titration using protein precipitation and complexation with palladiazo or other indicators.

Abstract

A simple, rapid and accurate method for the direct determination of Ca and the indirect determination of Mg in milk and yogurt by complexometric titration is proposed. The titration is based on the precipitation of proteins by salicylic acid followed by titration using a complexometric indicator. Palladiazo can be used as the indicator for the determination of Ca and Mg. The complexometric indicators Eriochrome Black T, Murexide and Calcein can also be used after treating milk with salicylic acid.