392 / 670
݉
= sample weight (g);
206
c = certified concentration of silver nitrate titrant (0.1000 mol/L or standardized concentration [
I
a];
207
ܸ
2
= AgNO
3
volume consumed at titration endpoint (mL);
208
ܸ
0
= AgNO
3
volume consumed at titration endpoint (mL) for Blank [
G
d];
209
݂
= dilution factor for preparation of reconstituted powder, RTF or concentrate. For samples
210
requiring the protein precipitation step [
F
a-c] an additional factor (e.g. for 25 g sample
݂
= 2)
211
will be needed.
212
35.4
5 = chloride weight in μg corresponding to 1 mL of 1 mol/L AgNO
3
;
213
100 = mass conversion to mg/100 g.
214
Under the repeatable analysis condition, the absolute difference between two independent test
215
results shall not exceed 2% of the arithmetic mean.
216
217
References
218
[1]AOAC SMPR 2014.015
219
220
[2] AOAC Official Method 2015.07. Chloride in infant formula and adult/pediatric nutritional
221
formula: Potentiometric titration method, 1
st
action 2015.
222
223
[3] AOAC Official Method 2015.08. Chloride in infant formula and adult/pediatric formula:
224
Potentiometry, 1
st
action 2015.
225
226
[4] GB/T 601-2002 Chemical reagent
–
Preparation of standard volumetric solutions.
227
228
229
230
231
Figure 1. Automatic titration endpoint recognition using dynamic titration (DET U) mode on
232
Methohm Titrodo 905
233
234
2015.07/2015.08 (February 2016)
Chlor-02/Chlor-04
FOR ERP USE ONLY
DO NOT DISTRIBUTE