AACC Approved Methods of Analysis, 11th Edition

Vitamins

AACC Method 86-10.01
Ascorbic Acid -- Indophenol-Xylene Extraction Method

VIEW METHOD

Objective
This method is based on the quantitative decolorization of a blue dye (2,6-dichlorophenolindophenol) by ascorbic acid, or vitamin C. The excess (unreacted) dye is extracted with xylene and measured in a spectrophotometer. In the absence of interfering materials, the amount of ascorbic acid present in the sample is proportional to the amount of dye decolorized.