AOAC 2019 First Action Methods

Table 2019.08A. Method performance requirements (as per AOAC SMPR 2016.001) SMPR 2016.001

K-ETOH

Analytical range (% ABV)

0.1 to 2.0

0.063-3.04

Limit of quantification (LOQ) (% ABV)

≤0.05

0.0041

Accuracy (% of mean spiked recovery over the range of the assay)

97 to 102

97 to 102

Repeatability (RSD r ), % Reproducibility (RSD R ), %

≤4 ≤6

<2

N/A

Table 2019.08B. Summary of enzymatic determination reaction procedure Wavelength 340 nm Cuvette 1 cm light path (glass or plastic with cap) Temperature Room temperature (15-25 ° C) Final volume 2.57 mL Sample solution 0.25–12 µg ethanol per cuvette Blank the spectrophotometer against air (without a cuvette in the light path) or against water Pipet into cuvettes Blank, mL Sample, mL Distilled water (~20 ° C) Sample 2.10 - 2.00 0.10 0.20 0.20 0.05 Cap cuvettes, mix by gentle inversion, and read the absorbances of the solutions (A 1 ) after approximately 2 min. Start the reaction by addition of: Suspension 4 (alcohol dehydrogenase) 0.02 0.02 Mix by inversion and read the absorbances of the solutions (A 2 ) at the end of the reaction (approximately 10 min). If the reaction has not stopped after 10 min, continue to read the absorbances at 1 min intervals until the absorbances increase constantly over 5 min. Solution 1 (buffer) Solution 2 (NAD + ) Solution 3 (aldehyde DH) 0.20 0.20 0.05

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