6. AOACSPIFANMethods-2018Awards

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to locally sourced samples that were fortified with lutein or β-carotene. All samples were prepared in triplicate, and the SPIFAN samples with substantial carotenoid concentrations were prepared at least 12 times (three replicates × 4 days). Intermediate precision (RSD iR ) was calculated as the RSD of all replicates. Repeatability (RSD r ) for triplicate samples was calculated as the RSD, and for larger samples sizes, it was estimated by performing a one-way analysis of variance on the intermediate precision data and calculating the SD from the within-day variance. Although SMPR 2014.014 does not specify criteria for intermediate precision, the requirements for repeatability and reproducibility are outlined in Table 8. Precision data are summarized in Tables 9 and 10. For all measurements in the range of 1–100 μg/100 g, RSD r was ≤5.8% for lutein and ≤5.1 for β-carotene. For measurements >100 μg/100 g, RSD r was ≤1.1% for lutein and ≤1.7 for

β-carotene. RSD iR ranged from 1.6 to 5.9% for lutein and from 0.7 to 6.3% for β-carotene for measurements >1 μg/100 g. For all measurements above 1 μg/100 g, the method met the precision requirements of the SMPR. Table 8. Precision requirements from SMPR 2014.014 Sample concn, μg/100 g Repeatability, % Reproducibility, % 1–100 8 15 >100–1300 5 10

Accuracy

Because there is currently no Certified Reference Material for carotenoids in infant formula and adult nutritionals,

Table 9. Precision data for lutein in SPIFAN matrixes and select additional matrixes a

cis -Lutein, μg/100 g RSD r

trans -Lutein,

Total lutein, μg/100 g RSD r

Matrix

SPIFAN code

, % RSD iR

, %

μg/100 g RSD r

, % RSD iR

, %

, % RSD iR

, %

n

< b

NA c

00847RF00 3

Child Formula Powder, Placebo Infant Elemental Powder, Placebo AN High-Protein RTF, Placebo d IF Milk-Based RTF, Placebo e SRM 1849a Powder IF Milk-Based Partially Hydrolyzed Powder IF Soy-Based Partially Hydrolyzed Powder Toddler Formula Milk-Based Powder IF Milk-Based Powder

NA

<

NA

NA

<

NA NA

00796RF 3

<

NA

NA

<

NA

NA

<

NA NA

00821RF00 3

<

NA

NA

3.3

3.8

NA

3.3

3.8

NA

AN High-Fat RTF, Placebo 00820RF00 3

2.0

3.8 NA

NA NA

4.2 0.5

4.6 5.7

NA NA

6.2 0.6

4.1 4.8

NA NA

EV4H2Q 3

<

CLC10-B 3 410057652Z 3

< <

NA NA

NA NA

< <

NA NA

NA NA

< <

NA NA NA NA

410057651Z 3

<

NA

NA

<

NA

NA

0.3

11.5

NA

4052755861 12 3.7

1.2

2.2

21.9

3.6

3.8

25.5

3.1

3.4

4044755861 12 2.1

3.6 NA NA NA

3.7 NA NA NA

9.4

5.0 NA NA NA 2.9 1.2 3.2 6.2 2.4 3.3 0.1 1.1

5.9 NA NA NA 5.2 1.6 3.4 NA 3.0 NA NA NA

11.5

4.1

5.1

AN Powder

00859RF00 3 00866RF00 3 00795RF 12

< < <

< < <

< < <

NA NA NA NA NA NA

Child Formula Powder IF Elemental Powder

IF with FOS/GOS Powder f 50350017W1 12 0.3

12.3

14.3

0.9 4.5

1.2 6.1

3.4 1.6

4.2 2.3

K16NTAV 39 1.6

3.3

5.5

IF Milk-Based Powder (control) IF Soy-Based Powder IF Milk-Based RTF AN High-Protein RTF

E10NWZC 12 0.6

5.7 NA 4.1 5.8 0.3 0.4

8.0 NA 4.4 NA NA NA

1.6 0.5 3.1 3.5

2.2 0.7 4.9 5.2

2.8

3.1 NA 3.4 NA NA NA

EV4H2R 3

<

16.9

00730RF00 12 1.9

2.9 3.2 0.2 1.0

AN High-Fat RTF

00729RF00 3

1.7

— g

AN High-Lutein Powder

3 21.4

82.1 127

104 140

Chocolate Pediatric Nutritional RTF

— 3 13.0

IF RTF

— 3

1.5

3.8

NA

3.9

1.4

NA

5.5

2.0

NA

a  For powder samples, results were calculated using a factor of 25 g powder/225 g reconstituted weight. b  < = Below the LOQ. c  NA = Not applicable. RSDr not calculated for concentrations

d  AN = Adult Nutritional. e  IF = Infant Formula. f  FOS/GOS = Fructooligosaccharide/galactooligosaccharide. g  — = Sample was sourced locally and was not part of the SPIFAN kit.