Theoretical Model for Calculating Ionic Equilibria in Milk as a Function of pH: Comparison to Experiment
Authors:
- 12 March 2010
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of Agricultural and Food Chemistry
- Vol. 58 (7) , 4440-4447
Abstract
Acidification is fundamental for the processing of milk into cheeses, caseins, and fermented dairy products. It is established that a pH decrease changes the ionic equilibria of milk, inducing the solubilization of micellar calcium phosphate. This study aimed to present a theoretical model calculating ionic equilibria in milk as a function of pH. From the pH and total concentrations of minerals and caseins, the model calculated the concentrations of all ionic species and their partition between micellar and aqueous phases of milk. As the pH decreased, the minerals present in the micellar phase were gradually displaced into the aqueous phase. The calculated concentrations of minerals were in a good agreement with the experimental ones determined from acidified milk. A very satisfactory accuracy of the calculations, estimated by a root-mean-square error (RMSE) value of 5% for Ca and Pi and a slope of the plot close to a unit, was obtained. The model is proposed for the simulation of ionic equilibria and the partition of salts between the aqueous and micellar phases of milk and dairy formulations during acidification.Keywords
This publication has 27 references indexed in Scilit:
- A model for predicting salt equilibria in milk and mineral-enriched milksFood Chemistry, 2009
- Measurement of ionic calcium in milkInternational Journal of Dairy Technology, 2006
- The application of microscopy and rheology to study the effect of milk salt concentration on the structure of acidified micellar casein systemsFood Hydrocolloids, 2005
- Effects of Acidification and Storage of Milk on Dissociation of Bovine Casein MicellesJournal of Agricultural and Food Chemistry, 1998
- pH-Induced dissociation of bovine casein micelles. II. Mineral solubilization and its relation to casein releaseJournal of Dairy Research, 1989
- Studies on micellar calcium phosphate: composition and apparent solubility product in milk over a wide pH rangeJournal of Dairy Research, 1984
- Calculation by computer of individual concentrations in a simulated milk salt solution: II. An extension to the previous modelJournal of Dairy Research, 1981
- Calculation by computer of individual concentrations in a simulated milk salt solution. IJournal of Dairy Research, 1981
- Etude de la teneur en éléments minéraux des produits obtenus lors de l'ultrafiltration du lait sur membraneLe Lait, 1974
- The use of ultrafiltration and dialysis in isolating the aqueous phase of milk and in determining the partition of milk constituents between the aqueous and disperse phasesJournal of Dairy Research, 1960