The pH value is an important factor that affects the color quality of anthocyanin-pigmented products. The chemical degrading or color fading of anthocyanins is highly pH dependent . The thermal stability of black carrot anthocyanins significantly decreases at pH values above 5.0 . The maximum formation of vitisin A ranges from pH 2.7-3.0, which changes the color of the model
solution and expresses approximately 11 (at pH 3) to 14 times (at pH 2) more color than the normal anthocyanins