A study on the concentration of sulfites in foods by online dialysis - ion chromatography method / 预防医学

ABSTRACT

Objective To establish a rapid and accurate detecting method for sulfite in food residues. Methods Applying an fluorine ionsalkali - stable liquid to extract ultrasonically. After removing the suspended substances by high - speed centrifugation,we used online dialysis - ion chromatography to determine sulfite. Chromatographic conditionswere set as followsMetrosep A Supp 5 - 150 / 4. 0 anion analysis column,using 3. 2 mmol / L sodium carbonate - 1. 0 mmol / L sodium bicarbonate 5% acetone as the eluent,with 0. 70 mL / min flow rate,20 μL injection volume and a conductivity detector. Results Sulfites( calculated as sulfur dioxide)manifested a good linear relationship when its concentration ranged from 0. 50 μg / mL to 50. 00 μg / mL,r = 0. 999 8. The minimum detection limit was 0. 54 mg / kg. The spiked concentrations were 10. 0 mg / kg,100. 0 mg / kg,500. 0 mg / kg,900. 0 mg / kg to samples. Relative standard deviation(n = 6,% )was 5. 04,1. 20,0. 56,0. 98,with the recovery rate between 85. 4% - 104. 4% . Conclusion This method is simple,rapid,with high sensitivity and accuracy of measurement,and which is suitable for the detection of sulfites content in food matrix.