2024-03-28T11:58:03+01:00
https://library.wur.nl/oai
oai:library.wur.nl:wurpubs/407617
2024-03-11
urn:nbn:nl:ui:32-407617
2024-03-11
urn:nbn:nl:ui:32-407617/mods
Accurate determination of the Ca2+ activity in milk-based systems by Ca-ISE: Effects of ionic composition on the single Ca2+ activitiy coefficient and liquid junction potentials
Gao
R.
314606904
0000000391898292
aut
van Leeuwen
H.P.
314610138
0000000391627425
aut
van Valenberg
H.J.F.
314599827
0000-0002-7228-2073
0000000396887912
aut
van Boekel
M.A.J.S.
068436394
0000000116886561
aut
text
info:eu-repo/semantics/article
2011
10.1016/j.foodchem.2011.04.076
79959963944
000293421400057
en
Calcium ion selective electrode (Ca-ISE) was found to underestimate the actual Ca2+ ion activity in simulated milk ultrafiltrate (SMUF) and milk. It is shown that the ionic compositional difference between conventional calibration solutions and milk type samples had a significant effect on the single Ca2+ activity coefficient, which generates the erroneous estimate of Ca2+ activities in SMUF and milk. This study tests new standards with ionic profiles similar to SMUF, aiming at the reduction of the errors generated by the compositional difference between conventional standards and milk samples. As a result, the new standards showed a significant improvement in the accuracy of Ca2+ activity and Ca2+ activity coefficient over the conventional standards. The systematic error is reduced from 20% to 5% for SMUF and from 44% to 15% for milk. In addition, the new standards generate liquid junction potentials that are practically insignificant
VLAG
WIMEK
Physical Chemistry and Colloid Science
Product Design and Quality Management Group
calcium-ion
selective electrode
ultrafiltrate
VLAG
WIMEK
Laboratorium voor Fysische chemie en Kolloïdkunde
Leerstoelgroep Productontwerpen en kwaliteitskunde
Food Chemistry
129
2
619
623
03088146
urn:nbn:nl:ui:32-407617/obj
2024-03-11
http://purl.org/eprint/accessRights/RestrictedAccess