AOAC ERP Gluten Assays - Dec 2018

Annex B

7.22 6.23 8.80 6.63 14.3 22.2 22.9 23.8 21.7 23.1 29.4 35.6 24.1 30.8 21.1 25.6 25.8 24.3 27.9 21.7 27.6 22.4 23.7

90% 78%

8.32 7.09 10.7 7.07 17.6 20.7 21.3 22.2 19.7 21.3 26.3 36.4 24.7 31.9 20.9 26.6 26.7 27.8 30.6 25.1 31.1 26.9 26.2

104%

7.98 6.65 9.47 7.04 15.8 24.7 24.1 26.4 24.6 26.3 32.5 33.5 25.0 29.4 21.2 25.4 26.4 25.2 27.9 20.8 26.2 23.3 24.0

104%

89%

89%

110%

133%

133%

Barley gluten 8 mg/kg

83%

88%

88%

179%

220%

220%

> Std 6

na

> Std 6

na

75.3*

na

70% 71% 74% 68% 72% 92% 75% 96% 66% 80% 81% 76% 87% 68% 86% 70% 74%

65% 67% 69% 62% 66% 82%

65% 67% 69% 62% 66% 82%

Wheat gluten 32 mg/kg

111%

114%

114%

77%

77%

100%

100%

Rye gluten 32 mg/kg

65% 83% 83% 87% 96% 78% 97% 84% 82%

65% 83% 83% 87% 96% 78% 97% 84% 82%

Barley gluten 32 mg/kg

One replicate for the barley containing porridge with a concentration of 8 mg/kg gluten was not included in the calculations since it is obviously an outlier with a concentration higher than standard 6 (> 80 mg/kg). For this sample there is a second value that is higher than expected. It was decided to include this value in the summary given in table 16. In case of porridge, the recoveries for all three contaminating grains were more comparable except the barley porridge as discussed above. The recoveries for rye and barley in porridge are almost identical to those in the cookies, whereas recoveries for wheat are higher in porridge, probably due to the lower level of heat treatment. All recoveries stated in table 15 are within the minimum performance criteria laid down in AOAC SMPR ® 2017.021. Table 16. Summary of results obtained for oat-based porridge incurred with gluten from wheat or rye or barley; mean concentrations and standard deviations derived from all three lots.

mean mg/kg

SD

CV

recovery

mg/kg

(%)

(%)

Wheat gluten 8 mg/kg Rye gluten 8 mg/kg Barley gluten 8 mg/kg Wheat gluten 32 mg/kg Rye gluten 32 mg/kg Barley gluten 32 mg/kg

7.86 8.54 9.39 24.1 27.3 25.7

1.35 0.80 3.63 3.21 4.71 2.87

17.2

82%

9.4

104% 121%

38.6 13.3 17.3 11.2

70% 86% 84%

Page 28 of 33

RIDASCREEN ® Total Gluten In-house validation report 2018-10-21