Impact of location, type, and number of glycosidic substitutions on the color expression of o-dihydroxylated anthocyanidins

•Glycosyl location, number, and size played important roles on anthocyanin color.•Different glycosylation patterns changed λmax and absorbance spectral shape.•C3 glycosylation of cyanidin hypsochromically shifted λmax, greatest by monoglycosides.•Cyanidin-3-glycosides showed higher color intensity in pH 4–6 than -3,5-glycosides.•Only cyanidin-3,5-glycosides expressed blue hues (pH > 7). Anthocyanins express many hues depending on environmental factors and structural aspects, of which aglycone structure and acylation have been considered most impactful. Effects of different glycosylations on anthocyanins’ colors are less known. Twelve cyanidin and 3-deoxy-cyanidin (luteolinidin) derivatives were isolated from red cabbage and black carrot hydrolysates and from black sorghum, diluted in pH 1–9, and analyzed by spectrophotometry and colorimetry. Location, number, and structure of glycosylations affected λmax and spectral shape of o-dihydroxylated anthocyanins, playing important roles on color expression. Generally, glycosylation of cyanidin decreased its λmax (≤27 nm), greatest decreases by 3-monoglycosylation. All cyanidin-glycosides appeared red in pH 1–3 and paled in pH 4–6. However, cyanidin-3-glycosides did not decolor completely like 3,5-glycosides. In alkaline pH, glycosylation patterns affected color more greatly: Cy-3-glycosides expressed maroon-purple hues (300–20°), 5-glycosides were green (100–115°), and only 3,5-glycosides expressed blue (240–250°). Luteolinidin derivatives shifted from yellow to red–purple hues with increasing pH.