Determination of total sulfur dioxide in wine and beer

INTRODUCTION

The method is used for the determination of the mass concentration of total sulfur dioxide (sulfurous acid and its salts, food additives E220–E228) in wine, wine materials, beer and beer products by capillary electrophoresis (CE) using Capel capillary electrophoresis system.

The mass concentration of total sulfur dioxide is regulated by normative documents to be held within 100–400 mg/L for different types of wine and wine materials and within 20–50 mg/L for beer products. According to certain regulations, for example, European and Russian legislation, it is allowed not to indicate on the labels the presence of sulfur dioxide in beverages if its concentration is less than 10 mg/L.

MEASURING METHOD

The CE method for the determination of mass concentration of total sulfur dioxide is based on a basic hydrolysis of the sample with its subsequent separation in a fused silica capillary under the influence of applied electric field. Identification and quantification of the analyzed sulfur dioxide is performed by indirect detection measuring UV absorption at 374 nm.