6. AOACSPIFANMethods-2018Awards

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1700 Martin & Campos-Gim É

nez: J ournal of AOAC I nternational V ol. 98, N o. 6, 2015

Table 3. Full set of data, part 1. All results are given in mg/100 g

Adult nutritional RTF high fat

Adult nutritional powder milk protein based

Infant formula powder soy based

Lab No.

SRM 1849a

Child formula powder

1 2 3 4 5 6 7 8 9

2.05 2.00 2.26 1.71 1.96 1.98 1.99 2.14 2.13 2.13 2.18 2.22 2.02 2.16

2.09 1.91 2.18 1.80 1.89 2.07 2.00 2.15 1.99 2.08 2.17 2.34 2.13 2.27

7.01 6.66 7.66 7.01 6.90 6.91 6.82 7.11 6.56 6.36 6.82 6.66 7.81 7.12

6.80 6.78 7.34 6.93 6.83 7.08 6.70 7.43 6.52 6.77 6.79 6.71 7.61 7.09

5.61 5.93 6.22 6.00 5.88 5.75 5.77 6.64 5.68 5.78 5.76 5.56 6.26 6.01

5.84 6.03 6.12 5.84 5.66 5.91 5.84 6.17 5.62 5.96 5.74 5.82 6.77 6.18

2.51 2.64 2.80 2.66 2.49 2.64 2.53 2.68 2.52 2.55 2.44 2.59 2.77 2.34 a

2.46 2.63 2.78 2.64 2.48 2.66 2.61 2.87 2.48 2.60 2.39 2.51 2.85 2.67 a

5.14 4.86 5.56 4.82 4.67 5.15 4.85 5.35 4.83 4.74 4.85 4.91 6.23 a

5.22 4.82 5.48 5.23 4.97 5.08 4.90 5.21 4.93 5.15 4.98 4.83 5.19 a

10 11 12 13 14

5.20

5.26

a  Outlier identified by the Cochran test.

study. Several minor comments were addressed to the Study Director and were taken into account in the final version of the method, which is presented in this paper.

Results and Discussion

Part 1

Sixteen laboratories initially agreed to participate in the collaborative study. One laboratory dropped out during part 1 due to issues related to availability of resources. One laboratory did not qualify for the second part of the collaborative study due to results out of the range of expected levels for both practice samples. Results for the two practice samples can be found in Table 1. The nonqualified laboratory’s results were not taken into account. Repeatability was 2.1 and 2.5%, respectively; reproducibility was 5.3 and 6.0%, respectively. HorRat values were below 1, at 0.59 and 0.68. As this precision estimate is calculated on nonblinded duplicates, it therefore cannot be used for the actual collaborative

Part 2

Fourteen laboratories sent a complete set of results. The statistical evaluation can be found in Table 2. Precision results (repeatability and reproducibility) are well within the limits stated in the Standard Method Performance Requirements (SMPR ® ) 2012.009 (10). Repeatability ranged from 1.3 to 3.3%, and reproducibility ranged from 4.1 to 7.0%. HorRat values were all below 1, from 0.33 to 0.69. Laboratory 14 was identified as an outlier for the product “Adult Nutritional Powder Milk Protein Based.” Laboratory 13 was an outlier for the products “Infant Formula Powder Soy

Table 4. Full set of data, part 2. All results are given in mg/100 g

Infant formula RTF milk based

Adult nutritional powder low fat

Adult nutritional RTF high protein

Infant formula powder part hydrolyzed soy based

Lab No.

Infant elemental powder

1 2 3 4 5 6 7 8 9

0.536 0.533 0.589 0.554 0.547 0.558 0.502 0.540 0.527 0.573 0.534 0.585 0.560 a 0.554

0.558 0.530 0.592 0.548 0.529 0.550 0.515 0.550 0.529 0.556 0.548 0.577 0.670 a 0.554

7.96 8.26 8.69 8.21 7.73 8.24 7.96 8.12 7.92 8.41 7.75 7.59 7.13 a

8.01 8.02 8.67 8.00 7.39 8.18 8.05 7.90 7.84 8.25 8.07 7.57 8.55 a

1.54 1.49 1.67 1.58 1.37 1.61 1.55 1.62 1.54 1.59 1.62 1.69 1.64 a

1.52 1.46 1.68 1.58 1.41 1.59 1.48 1.59 1.50 1.57 1.68 1.66 1.45 a

6.35 6.22 7.18 6.09 6.74 6.87 6.57 6.62 6.38 6.93 6.64 6.33 7.00 6.60

6.25 6.35 7.22 6.78 6.28 6.69 6.61 7.00 6.27 6.85 6.58 6.34 7.59 6.85

3.68 3.95 4.19 3.92 3.46 3.81 3.95 3.71 3.58 3.91 3.81 3.63 4.18 4.06

3.63 4.01 4.17 3.94 3.54 3.83 3.81 3.73 3.66 3.99 3.80 3.69 4.03 4.05

10 11 12 13 14

8.41

8.55

1.62

1.66

a  Outlier identified by the Cochran test.