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FOR EXPERT REVIEW PANEL USE ONLY
NOT FOR DISTRIBUTION
2
Conclusion:
For higher protein levels in the test sample the precipitation of protein by adding Carrez I and II, followed
by a centrifugation step is included (taken from the sample preparation of Chlor 04). The added nitric acid
solution is stronger (16 %) than those of Chlor 2, where a 2% nitric acid is applied to get a low pH value. The
automatic titration with 0.1 mol/l AgNO
3
and a combined silver electrode is in both methods equal.
Method Scope/Applicability:
The method is applicable for the determination of chloride in milk, milk powder, whey powder, infant
formula and adult nutritionals.
General comments about the method:
The sample preparation is easy to perform and does not require special glassware or equipment.
Method Clarity:
The combined method is very clearly described and easy to follow.
Pros/Strengths:
Simple sample preparation
Method also applicable for other food matrices than IMF
Cons/Weaknesses
The method is not specific for chloride as the analyt is not determined directly. Interferences from
bromide and iodine may occur, but is unlikely due to low levels of those anions in IMF and Adult
Nutritionals.
Supporting Data
General Comment:
–
Method Optimization: no remark
Performance Characteristics:
Analytical Range:
0.35 – 1060 mg/100g reconstituted product
SMPR: 5 – 500 mg/100g reconstituted product
Linearity:
-
SMPR: not required
LOQ:
Chlor 2: 1,4 mg/100g
Chlor 4: 2,2 mg/100 ml
SMPR: ≤ 5 mg/100g reconstituted product
Accuracy/Recovery:
Chlor 2: 100 %
Chlor 4: NIST 1849a: 98 %
SMPR: 95 – 105 %
Precision (RSD
r
):
Chlor 2: 0,03 – 1,6 %
Chlor 4: 0,1 – 1,8 % %
SMPR: ≤ 2 %
Chlor-02/Chlor-04 Review Forms