Anthocyanin content, expressed as cyanidin- 3-glucoside equivalents, was calculated as: anthocyanin content (mg/L)=(ApH 1−ApH 4.5)×449.29×DF×1000/(26,900×1) where ApH 1 and ApH 4.5 are the absorbance of the BCE filtrate in a pH 1.0 and a pH 4.5 buffer, respectively