6. AOACSPIFANMethods-2018Awards

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Table 2011.10A. SLV repeatability precision data for vitamin B 12 Sample type

No. of replicates (duplicates on multiple days) Mean, µg/100 g RTF

SD r

RSD r

, %

42.4 a 0.415 0.236 0.355 0.377 0.257 0.299

Infant formula (NIST SRM 1849a) Infant formula powder soy-based Infant formula powder milk-based Infant formula RTF milk-based

18 12 12 12 12 12 12 12 12 12 12 12

1.39

3.27 3.62 3.52 2.34 3.50 3.51 4.72 2.21 2.36 2.81 4.13 2.81

0.0150 0.0083 0.0083 0.0132 0.0090 0.0141 0.0250 0.0225 0.0463 0.0223 0.0187

Infant formula powder partial hydrolyzed milk-based Infant formula powder partial hydrolyzed soy-based

Adult nutritional powder milk-based Adult nutritional RTF high protein

1.13

Child formula powder

0.955

Adult nutritional RFT high fat Infant elemental powder Adult nutritional powder low fat a  Results in µg/kg powder.

1.65

0.540 0.666

Table 2011.10B. SLV accuracy data for vitamin B 12

—spike recoveries at 100% of native level

No. of replicates (duplicates on multiple days)

Native level, µg/100 g RTF Recovery, % RSD, %

Sample type

42.6 a 0.404 0.236 0.326 0.347 0.248 0.298

Infant formula (NIST SRM 1849a) Infant formula powder soy-based Infant formula powder milk-based Infant formula RTF milk-based

4 6 4 6 4 6 4 6 4 4 6 4

95.7 98.2 104 96.4 98.2 95.7 97.4 98.6 98.2 102 105 95.1

5.32 5.32 4.32 8.17 6.34 2.51 3.86 6.76 7.98 1.61 4.45 4.38

Infant formula powder partial hydrolyzed milk-based Infant formula powder partial hydrolyzed soy-based

Adult nutritional powder milk-based Adult nutritional RTF high protein

1.12

Child formula powder

0.109

Adult nutritional RFT high fat Infant elemental powder Adult nutritional powder low fat a  Results in µg/kg powder. b  ND = Not detected.

1.59 ND b

0.639

Table 2011.10C. Interlaboratory study results for vitamin B 12

Mean, µg/100 g RTF

Total No. labs

Total No. replicates

, % HorRat a

Sample type

SD R 3.86

RSD r

, % RSD R

SD r

43.7 b

Infant formula (NIST SRM 1849a) Infant formula powder soy-based Infant formula powder milk-based Infant formula RTF milk-based

10 10

20 20 18 18 22 20 20 20 16 14 18 20

3.01

6.90

8.84 7.13 8.90 15.7 18.6 19.5 13.8 17.5 3.54 11.5 11.1 9.23

0.34 0.20 0.22 0.40 0.50 0.50 0.36 0.55 0.11 0.38 0.32 0.27

0.428 0.0208 0.0305 4.85 0.227 0.0111 0.0202 4.90 0.272 0.0257 0.0427 9.46 0.373 0.0200 0.0694 5.35 0.250 0.0244 0.0487 9.77 0.300 0.0270 0.0416 8.99

9 9

Infant formula powder partial hydrolyzed milk-based Infant formula powder partial hydrolyzed soy-based

11 10 10 10

Adult nutritional powder milk-based Adult nutritional RTF high protein

1.08

0.0730 0.190 6.74

Child formula powder

8 9 9

0.967 0.0289 0.0342 2.98

Adult nutritional RTF high fat Infant elemental powder Adult nutritional powder low fat

1.48

0.122 0.171 8.23

0.543 0.0169 0.0603 3.11 0.636 0.0348 0.0587 5.47

10

a  HorRat = RSD/PRSD; PRSD = 2C –0.15 (C = concentration by mass fraction). b  Results in µg/kg powder.