OMB Meeting Book - Jan. 11, 2018

Table 2015.08B. Recovery results of spiking experiments for chloride

+ 50% of native value

+ 100% of native value

Matrix

Native chloride, mg/100 g Average, % RSD, % Average, % RSD, %

SRM NIST 1849a

68.5 46.1 36.8 20.0 36.4 42.4 46.2 40.3 38.6 39.3 46.5 56.1 44.2

104.0 102.0 101.0 103.0 101.0 101.0 102.0 102.0 101.0 100.0 100.0 101.0 103.0 101.0 102.0

2.8 2.1 1.5 1.2 1.2 1.0 1.4 1.6 1.5 1.9 0.5 1.2 3.2 0.2 1.6

103.0 100.0 101.0 101.0 100.0 100.0 100.0 101.0 100.0 101.0 100.0 100.0

1.3 1.5 1.5 1.1 0.7 1.8 1.5 1.8 1.3 1.2 0.9 0.4 1.0 0.5 1.9

Child formula powder Infant elemental powder

Infant formula RTF, milk based (SPIFAN blank milk formula)

Adult nutritional powder, milk protein based

Infant formula powder partially hydrolyzed, milk based Infant formula powder partially hydrolyzed, soy based

Adult nutritional powder low fat

Child formula powder Infant elemental powder

Infant formula powder, milk based Infant formula powder, soy based

Infant formula RTF, milk based (SPIFAN control milk formula)

99.0

Adult nutritional RTF, high protein Adult nutritional RTF, high fat

154.5 162.2

100.0 103.0

( b )  AgNO 3

dried for 2 h at 110 ± 2°C. Dissolve in water and make up to the mark in a 1000 mL volumetric flask. F. Sample Preparation Milk product, infant formula, and adult/pediatric nutritional .— Mix well to ensure that sample is homogeneous. Powder samples were reconstituted by dissolving 25 g powder sample in 200 mL warm water (40°C). G. Instrument Operating Conditions Connect the combined silver electrode to the automated titration apparatus according to the manufacturer’s instructions. Ensure that the titration vessels are correctly placed on the autosampler and there are enough reagents, both 2% (v/v) nitric acid and 0.1 M AgNO 3 .

solution, 0.01 M (optional) .—Into a 1000 mL

volumetric flask, pipet 100 mLAgNO 3 solution, 0.1 M. Make up to the mark with water. Check the titer by titration of 20 mL exactly 0.01 M NaCl solution. ( c )  NaCl solution, 0.01 M (optional) .—Into a 1000 mL volumetric flask pipet 100 mL NaCl solution, 0.1 M. Make up to the mark with water. ( d )  Standardized AgNO 3 solution, 0.1 M.— If no ready-to-use AgNO 3 standard solution is available, weigh 16.9890 ± 0.0005 g AgNO 3 previously dried for 2 h at 120 ± 2°C. Dissolve in water and make up to the mark in a 1000 mL volumetric flask. Check the titer by titration of 20 mL exactly 0.1 M NaCl solution. ( e )  NaCl solution, 0.1 M .—If no ready-to-use NaCl standard solution is available, weigh 5.8440 ± 0.0005 g NaCl, previously

Table 2015.08C. Comparison of SLV data with SMPR Parameter SMPR 2014.015

Single-laboratory validation

Matrixes

SLV test matrixes kit (17 samples)

All forms of infant, adult, and/or pediatric formula (powders, RTF liquids, and liquid concentrates)

LOQ, mg/100 g

5 mg/100 g a

1.4 mg/100 g a

Analytical range, mg/100 g

5–500 mg/100 g a

1.4–1060 mg/100 g

Spike recovery, %

95–105

SPIFAN samples (15) were spiked at two levels of chloride on 6 separate days Spike level 1: Average recoveries of 101.6% (range 101–103%) Spike level 2: Average recovery of 100.6% (range 99–103%)

Bias versus SRM

NIST 1849a informational value = 710 mg/100 g

Value found = 685 mg/100 g, recovery = 97.2%, no bias at 95% confidence level = 0.31% (17 products), range 0.03–1.60%; concentration range evaluated 20–167 mg/100 g RTF Average RSD r

RSD r

(repeatability), %

≤2

R (reproducibility), %

≤4

RSD RSD

IR (intermediate reproducibility) = 0.54% (17 products); range 0.09–2.77%; concentration range evaluated 20–167 mg/100 g RTF a  Concentrations apply to (a) RTF liquids as is; (b) reconstituted powders (25 g into 200 g water); and (c) liquid concentrates diluted 1:1 by weight. Not assessed Average RSD R

© 2015 AOAC INTERNATIONAL

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