Ascorbic acid, anthocyanin stability

Garcia-Viguera, C. and Bridle, R, Influence of structure on colour stability of anthocyanins and flavylium salts with ascorbic acid, Food Chem., 64, 21, 1999. 

De Rosso, V.V. and Mercadante, A.Z., The high ascorbic acid content is the main cause of the low stability of anthocyanin extracts from acerola. Food Chem., 103, 935, 2007. 

The color of anthocyanins containing media depends on different factors. The most important are structure and concentration of anthocyanin pigments, pH, and presence of copigments and metallic ions, all of which influence the color shade. Also important are the temperature and presence of oxygen, phenoloxidase, ascorbic acid, and sulfur dioxide, all of which influence the anthocyanins degradation rate and color stability. 

From the technological perspective, the most important property of anthocyanins is colour and its stability, which is usually relatively low. The main factors affecting the colour stabiUty of anthocyanins are the structure of the molecule, presence of certain enzymes, pH, temperature, presence of oxygen and exposure to radiation. Anthocyanins may produce various coloured or colourless reaction products in reactions with other food components, such as, for example, ascorbic acid, sulfur dioxide, other phenols and metal ions. 

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