Determination of ascorbic acid in wines by automatic potentiometric titration

The determination of ascorbic acid in wines used automatic potentiometric titration was investigated and compared with chemical titration method. The linearity, repeatability, reproducibility and recovery of the determination method were studied.The results showed that the potentiometric titration method was used to determine ascorbic acid in white and red wines directly.The linear range was 0.01⁰.30 g/L ( r = 0.9997) . The RSD value of repeatability and reproducibility were less than 0.3%.The recoveries in the range was 98.0% to 99.6%. And there was no significant difference ( α = 0.05) in measurement values between potentiometric titration method and national standard method. This study suggested that the potentiometric titration method had good linearity, repeatability and reproducibility, which was easy to operate without decoloring treatment. It would be feasible and practicable in determining ascorbic acid in wines.