OMA Protocol Review: OMAMAN-56 Sulfites in Shrimp

2 in case of 50-300 mg/kg Measurement range) into the measurement cuvette and wait for the process to end.

2.3. The message “Biotest activated. Ready for calibration” will appear on the screen.

2.4. Replace the cuvette’s contents with 10 mL of new measurement solution.

3) Calibration.- The calibration is carried out by making two additions of the sulfite standard to the measurement cuvette. To plot the calibration line, the equipment will take the standard into account, the variation in intensity brought about by the initial addition of the sulfite standard and the sum of the variations in intensities brought about by both additions. 3.1. Press calibrate, verify the proper placement of the cuvette with 10 mL of SUL Measurement Solution and press CONTINUE. 3.2. Wait for the equipment to emit an acoustic signal. Press CONTINUE and add sulfite standard into the measurement cuvette (2 mL of SUL Standard 1 in case of 30-150 mg/kg Measurement range or 1 mL of SUL Standard 2 in case of 50-300 mg/kg Measurement range). This is addition 1. Note : It is important to add the Calibration Standard immediately after pressing the CONTINUE button to record the current intensity correctly at the time of adding it. 3.3. Wait for the equipment to register the change in intensity and emit an acoustic signal again. Press CONTINUE and add sulfite standard again (2 mL of SUL Standard 1 in case of 30-150 mg/kg Measurement range or 1 mL of SUL Standard 2 in case of 50-300 mg/kg Measurement range). This is addition 2. 3.4. Wait until the parameters of the calibration appear on the screen together with a message of “calibration OK” or “calibrate again”.

3.5. Replace the cuvette’s contents with 10 mL of new SUL Measurement Solution.

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