[Determination of sulfite residues in foods by using the modified rankine apparatus and HPLC].

A method for measuring sulfite residues in foods by using the modified Rankine apparatus and HPLC was developed. Sulfites released from foods by bubbling of nitrogen gas and heating for 15 minutes with an electric burner weRe absorbed in 1% triethanolamine solution and detected as sulfite ion by HPLC with a UV detector at 240 nm, using an anion exchange column, IonPac AS9-SC, with 1.8 mmol/L sodium carbonate-1.7 mmol/L sodium hydrogen carbonate solution as the mobile phase. The recoveries of sulfites added to 3 kinds of foods were 98-102%, and the determination limit was 0.001 g/kg. The sulfite values in various kinds of foods determined by the proposed HPLC method were consistent with those obtained by the alkaline titration method and the colorimetric method.