Rapid determination of sulfites by microextraction-ion chromatography in red wine

Abstract

Objective: In view of the improvement of the national standard method of distillation pretreatment, combined with the advantages of ion chromatography, a rapid determination of sulfite by microextract-ion chromatography in red wine was established. Methods: Sulfur dioxide was released by microextraction device, which was absorbed by sodium hydroxide solution to form sulfite, and then oxidized to sulfate. The samples were then filtered by 0.45 μm filter and determined by ion chromatograph. Results: The concentration of sulfite ion in range of 1.0~50 mg/L showed a linear relationship with the peak area, with correlation coefficient of 0.999 9, and the detection limit was 0.24 mg/L. The average recoveries of different levels of sulfate were 95.2%~99.1%, and the relative standard deviations (RSD) were 6.84%~8.65%. Conclusion: The method has the advantages of simple and fast pretreatment operation, reduced impurity interference significantly, and is suitable for the detection of batch samples.

Keywords

• micro extraction
• ion chromatography
• red wine
• sulfites