2.6. Anthocyanins determination
Anthocyanins were determined by the pH-differential method
(Lee, 2005). Anthocyanin pigments change colour with pH. The
absorption of the sample was measured at pH 1.0 and pH 4.5.
The difference in absorbance is proportional to the anthocyanin
content. The total anthocyanin content was expressed as cyanidin-
3-glucoside equivalents and calculated via the following
formula: