ISSN:
1750-3841
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
The combined effects of pH (3.0–3.8) and anthocyanin concentration on the color and spectral characteristics of aqueous solutions were studied with a number of anthocyanin glucosides. Color data, obtained with a Hunter Color Meter, were treated by plotting the “L” values against the corresponding “a,”“b,” hue angle and saturation chromaticity values, showing that maximum chromaticity values occurred at middle “L” values, and that these chromaticity values were increased when the pH was decreased. The predominantly red hues of anthocyanin solutions had more purple character at very low or very high “L” values, and when the pH was raised, or the anthocyanin had a greater degree of hydroxylation or methoxylation or when the anthocyanin was glycosylated in the 5 position as well as the 3 position. The range of hues, from orange to purple, obtainable with individual anthocyanins was dependent on the type of anthocyanin. At equal concentrations and pH the 3-monoglucosides gave darker solutions (lower “L” values) than 3,5-diglucosides. Wavelengths of maximum absorbance decreased as the anthocyanin concentration increased. The results might find application in standardizing the color of beverages containing anthocyanins.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-2621.1974.tb02886.x
