OMA Protocol Review: OMAMAN-56 Sulfites in Shrimp

Mediu m level 2

OMA 3 Day 1

125

-

-

3.1

2.5

BIOFIS H

5 Day 1/

120

96

-4.7

3.7

3.1

Analyst 1

(30- 150

5 Day 2/

120

96

-4.5

1.8

4.5

Analyst 2

mg/kg range)

High Level

OMA 3 Day 1

294

-

-

3.0

1.0

BIOFIS H

5 Day 1/

276

94

-17.7

8.6

3.1

Analyst 1

(50- 300

5 Day2/

283

96

-10.8

7.9

2.8

Analyst 2

mg/kg range)

BOILED SHRIMP

0 100 200 300

y = 0.9271x + 3.6327 R² = 0.99998

0 50 100 150 200 250 300 350 Biofish results (mg/kg) OMA results (mg/kg)

Figure 11. Graph of mean Biofish results vs OMA results for boiled shrimp fortified with sodium metabisulfite.

Limit of detection (LOD) and limit of quantitation (LOQ) Limit of detection (LOD) and limit of quantitation (LOQ) were determined by first plotting S r against the mean results and performing linear regression for each matrix and each quantification range. Next, LOD was calculated as

X

( ) b s m

0 3.3 1 1.65 + −

LOD =

X

s

where, is the mean analytical value of the known negative matrix; is the slope of the plot. LOQ is then estimated as LOQ = 3 x LOD. 0 m

is the intercept of the plot; and

b

22