Dephosphorization of Casein by Heat Treatment. I. In Caseinate Solutions

Abstract

Heat treatment of 3% Na (a- and B-) and unfractionated caseinate solutions at 110[degree] to 140[degree] C progressively released the casein phosphate as inorganic orthophosphate. Under the conditions studied, all of the samples conformed to first-order kinetics. The energy of activation E was calculated to be 28-29 kcal/mole of phosphate, the same as for the dephosphorization of O-serine phosphate. Calculations of the entropy change [DELTA]s* for the activated complexes of casein phosphate and O-serine phosphate gave a value of -5 cal/mole/degree. Structurally the molecules are considered to have been altered very slightly from the original. The data indicate that the hydrolysis of P from casein proceeds through an oxygen-phosphorus fission.