AOAC SPIFAN WPC ERP-Final Action Review (Nov. 2017)

2016.15 (Nov. 2017) - WPC-31 Publications-Final Action Review

FOR ERP USE ONLY DO NOT DISTRIBUTE

AOAC Official Method 2016.15 Quantification of whey protein content in milk-based infant formula powders SDS-CGE (Sodium Dodecyl Sulfate – Capillary Gel Electrophoresis)

First Action 2016 Final Action 2017

(Applicable to determine the whey to casein protein ratio, ranging from 20:80 to 80:20, in bovine milk-based infant formula powders. This method is not applicable to the analysis of hydrolyzed or plant protein-based infant formulas.) Caution: Correct personal and environmental safety standards shall be used while performing this analytical method. Laboratory personnel handling solvents, acids, and reagents should be knowledgeable of their potential hazards. Consult the Material Safety Data Sheets (MSDS) for information on the hazards and take proper precautions. Transfer solvents including β- mercaptoethanol and acids inside efficient fume hoods and extractors. Because of β-mercaptoethanol buildup, perform measurements in a well-vented room. Ideally, install the machine directly in a fume hood. Ensure all glassware is free from chipping and hairline cracks.

Table 2016.15A: Interlaboratory Study Results that support acceptance of the method.

Repeatability

Reproducibility

Material

No. of Labs

Mean (Whey %)

Recovery %

RSD R (%)

Level*, (Whey %)

RSDr (%)

HORRAT

Matrix

Whey dominant infant formula

53

19

56.71

106

1.67

3.14

1.44

Third age formula

40

19

41.69

104

2.11

4.22

1.85

α-Lac enriched Whey formula

65

19

65.51

100

1.44

2.18

1.02

NIST SRM 1849a #

32

19

43.11

134

3.51

5.94

2.62

Whey dominant infant formula

60

19

60.69

101

2.11

2.37

1.11

Third age formula

50

19

49.99

100

1.63

3.57

1.61

Formula with added LF Formula with added α-Lac Formula with added α-Lac Formula with added α-Lac Formula with raw milk Formula with reduced CGMP §

≥ 60

18

63.63

106

0.92

2.37

1.11

70

19

73.24

105

0.83

2.30

1.10

70

19

68.92

98

1.67

2.59

1.22

70

19

69.26

99

1.82

3.20

1.51

≥ 60

19

63.40

106

2.09

3.33

1.55

70

19

69.41

99

1.57

2.89

1.37