text: can you do a acid-base titration to find out the vitamin c concentration of a citrus juice?   no. citrus juice contains mainly citric acid, and smaller amounts of ascorbic acid. titrating with a base does not differentiate between the two. you can get the total acid concentration though.  the following link demonstrates redox titration to determine vitamin c. this works because the oxidant (indolphenol) does not react with citric acid.