The cyclic voltammetric method, which is based on the redox properties of ascorbic acid, was adopted to determine the concentration of vitamin C in apple juices. Recorded on voltammograms, the oxidation current of ascorbic acid was linearly dependent on the ascorbic acid concentration (a linear calibration curve was found in the range of up to 150 mg ascorbic acid/100 cm³ solution). The standard addition technique was used to determine the ascorbic acid concentration. To verify results, the titrimetric method was used. Differences between concentrations of vitamin C determined using the cyclic voltammetric and titrimetric methods are lower than 1 mg (in comparison to concentrations of ascorbic acid about 50 mg/100 cm³ of juice). The method – easy for automation – can be used directly without special preparation of studied apple juices samples before measurement of the vitamin C concentration.

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