OMA Protocol Review: OMAMAN-56 Sulfites in Shrimp

Figure 5. Calibration results

( d ) Standard measurement.-- The calibration status should be tested using the STANDARD option after every 10-15 measurements or after the device has not been running for 30 minutes. ( 1 ) Press

Standard in the analysis option, check that the cuvette is correctly fitted and filled with SUL

Measurement Solution and press CONTINUE to begin the Standard measurement. ( 2 ) Wait until the

device records the measurement target and it issues a sound signal. Press CONTINUE and add the

Calibration Standard (4 mL of SUL Standard 3 for the 7-30 mg/kg range; 2 mL of SUL Standard 1 for the

30-150 mg/kg range; or 1 mL of SUL Standard 2 for the 50-300 mg/kg range) into the measuring cuvette.

( 3 ) Wait until the “Biosensor calibrated” or “Biosensor recalibrate” message appears. (4) Replace the

contents of the cuvette with 10 mL of new SUL Measurement Solution. If “Biosensor calibrated”

message appeared, proceed to Determination . If “Biosensor recalibrate” message appeared, return to

Step ( c ) Calibration .

Determination ( a ) Press the option ‘Turrax’ (for 30-150 or 50-300 mg/kg range) or the option ‘Sample’ (for 7-30 mg/kg range). Check that the cuvette is correctly fitted and filled with 10 ml of SUL Measurement

Solution and press CONTINUE to begin the sample measurement.

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