Approaches to the phytomelanin color characteristics assessment for use as an alternative to cocoa powder

The work is devoted to the study of approaches to assessing the color characteristics of dark-colored vegetable powders used in the production of semi-finished confectionery products. The purpose of the work is a comparative study of the color characteristics of cocoa powder and phytomelanin samples, for the use of the latter as a possible replacement for part of the cocoa powder in the manufacture of confectionery glazes. The intensity and shade of the color of ethanol solutions of cocoa powder and samples of phytomelanin from buckwheat husks, the chromatic structure of the color of the studied samples and the determination of color differences between the samples using the CIE L*a*b* method were studied. It has been established that the color intensity of melanin samples exceeds that of cocoa powder by 1.8-2.0 times, which indicates a higher coloring ability of melanin. The value of the color shade for melanins is also higher compared to the samples of cocoa powder (by 16 %), thus, one can indicate a greater intensity of yellow-brown tones in the color of melanin. It is shown that the values of relative color coordinates and chromaticity coordinates in the CIE 1931 XYZ system are similar for the studied samples. It was found in the experiment that the light fastness of the cocoa powder sample turned out to be almost 2 times lower compared to the melanin samples. Thus, the visual differences between the color of cocoa powder and melanins are insignificant, so melanin can potentially be considered as a partial replacement for cocoa powder in confectionery recipes. In addition, in the composition of food systems, melanin shows a higher stability to light. The use of spectrophotometric methods to assess the color characteristics of melanin in the future will allow the development of an evaluation scale for simpler and more reproducible methods for assessing the color of melanin, for example, methods of visual comparison with standards.