Effect of disaccharides on ion properties in milk-based systems.
The mean spherical approximation (MSA) theory is used to explain the impact of sugars on ion properties in milk-based systems by taking into account electrostatic interactions and volume exclusion effects. This study first focuses on the changes in Ca(2+) activity and pH in a solution consisting of CaCl(2), KCl, and K(3)citrate, as a function of sucrose concentration. MSA model calculations were compared with experimental results, and the model satisfactorily describes the ion properties. The excluded volume effects appear to account for a considerable increase in activity coefficient of the ions. This offers a sufficient explanation for the increase in Ca(2+) activity and the decrease in pH in milk-based systems with added disaccharides. In addition, hydration of milk proteins seems to enhance ion pair formation in milk. All disaccharides lead to similar modification of the thermodynamic properties of milklike systems, confirming that the observed effects are primarily due to volume exclusion effects.
Gao
Ran
R
Product Design and Quality Management Group, Wageningen University, PO Box 8129, 6700 EV Wageningen, The Netherlands.
van Leeuwen
Herman P
HP
Temminghoff
Erwin J
EJ
van Valenberg
Hein J
HJ
Eisner
Matthias D
MD
van Boekel
Martinus A
MA
D000818:Animals; D002118:Calcium / Q000032:analysis / Q000737:chemistry; D002122:Calcium Chloride / Q000737:chemistry; D004187:Disaccharides / Q000008:administration & dosage*; D004553:Electric Conductivity; D004573:Electrolytes / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008892:Milk / Q000737:chemistry*; D011189:Potassium Chloride / Q000737:chemistry; D019357:Potassium Citrate / Q000737:chemistry; D012996:Solutions / Q000737:chemistry; D055672:Static Electricity; D013395:Sucrose / Q000008:administration & dosage / Q000032:analysis; D013816:Thermodynamics
D004187:Disaccharides; D004573:Electrolytes; D012996:Solutions; D013395:Sucrose; D011189:Potassium Chloride; D019357:Potassium Citrate; D002122:Calcium Chloride; D002118:Calcium