In this study, different solutions to extract vitamin C were tested. High-performance liquid chromatography was chosen and the
conditions were based on isocratic elution in reverse phase column. Dehydroascorbic acid was determined indirectly after its reduction
using dithiothreitol. The use of metaphosphoric acid to stabilize the vitamin C was shown to be required and it was necessary to
neutralize the pH of the extract to apply dithiothreitol. The average recovery was 90% in collard and tomato samples. The presence
of oil did not interfere in extraction and the methodology can be used to analyze stir fried vegetables.