DIFFUSION OF MINERALS FROM INFANT FORMULAS THROUGH A SEMIPERMEABLE MEMBRANE COMPARED WITH BREAST MILK AND AN EXPERIMENTAL SOLUTION

Abstract

This paper is aimed at assessing the possibility of using passive transport processes through semipermeable membranes of cellulose acetate as a criterion for the evaluation of the properties of adapted milk formulas and breast milk. The content of potassium and sodium ions and that of calcium and magnesium in the calcined milk mixtures prepared for the analysis were determined by the potentiometric and titrimetric methods, respectively. The data obtained was used to estimate the rate of diffusion from reconstituted milk mixtures. The permeability coefficients of potassium, sodium, magnesium and calcium ions were calculated for reconstituted milk mixtures and an experimental solution that simulated the milk mixtures used in the study in terms of their ionic composition. The diffusion of ions in vitro, which was evaluated using the permeability coefficient, is demonstrated to be identical to the processes of absorption through the gastrointestinal canal wall. The results of the study demonstrate that, in contrast with breast milk, no caseinate cell phosphate complex forms during the reconstitution of adapted milk mixture. This is evidenced by a higher diffusion rate of calcium and magnesium ions from reconstituted adapted milk mixtures than that from breast milk. The calcium and magnesium ions are absorbed less easily from infant formulas than from breast milk.